THE METAL-MARKSFamilyRiodinidaeThis small family of very small butterflies contains five genera and a dozen species found in the United States and Mexico. Only two, however, occur in the eastern region and only one extends much north of the Gulf states. Aside from certain peculiarities of the wing-venation (acostal and a humeral vein on the hind wings) these Metal-marks may be known by their minuteness and the bright metallic markings on the brown wings.Both our eastern species belong to the genusCalephelis. The Small Metal-mark (C. caenius) has been collected in Florida and Georgia. The wings are rusty red on both surfaces, brighter below than above, and marked with blackish spots that almost converge to form stripes; in addition to which there are, beyond the middle of each wing, two lines made by special scales that glisten with a steel glitter. The wings expand only about three quarters of an inch. So far as I can learn, the egg, larva, or pupa have never been described.The Large Metal-mark is called by scienceCalephelis borealis, but it deserves the latter name only in the sense that it is more northern than its allies. It has been collected as far north as New York and Michigan, but it seems to be very seldom found, at least in eastern regions. It expands a little more than an inch. The general color of the wings is yellowish brown, marked with blackish dots and lines, together with rows of steely spots on the under surface. In this case also the life-history is unknown.Seepage 236THE SNOUT BUTTERFLY IN FLIGHT AND AT RESTSeepage 62GIANT SWALLOWTAIL JUST OUT OF THE CHRYSALISFrom a drawing by W. I. BeecroftSeepage 233THE MONARCH BUTTERFLYCaterpillar feeding; caterpillar hung up for pupation; chrysalis, and adultTHE GOSSAMER-WINGSFamilyLycaenidaeThe daintiest and most delicate of all our butterflies are included among the Gossamer-wings. Their bodies are small and slender, their antennae ringed with white and almost threadlike, their wings thin and of exquisite beauty. Many of them are marked with the slenderest of tailed projections from the hind wings. When the face is viewed from in front it is seen to be much narrower than its height. At the insertion of the antennae the eyes are notched, and they are also more or less surrounded with white scales. Most of the caterpillars have oval, slug-shaped, smooth bodies, with the under surface flattened, and very small heads, which in many species can be extended by means of an extensile neck. The chrysalids are held in place by silken threads both at the tail and over the middle. They are rounded, short, and stout.Notwithstanding their small size, the Gossamer-wings are among the most spritely of all our butterflies. They seem indeed winged sprites, playing everywhere, in fields and open woods, along roads, lanes, and brooks, in door-yards and gardens—wherever, in fact, a bit of open space invites their presence. Not alone upon the wing but even when at rest does their liveliness appear. For most of these butterflies have the curious habit of keeping the hind wings in motion after alighting, rubbing them against each other in a vertical plane or "moving them backward and forward when half expanded." These habits are so fixed that when one sees a butterfly thus engaged one can pretty certainly conclude it is a member of this family.The Gossamer-wings are commonly separated into three rather distinct tribes—the Hair-streaks, the Coppers, and the Blues. The characteristic features are these:Three branches arising from the radius of each front wing. Under surface of hind wing commonly marked with threadlike streaks: the Hair-streaks.Four branches arising from the radius of each frontwing. Under surface of hind wing commonly marked with spots rather than lines.Colors brownish red: The Coppers.Colors blue: The Blues.THE TRIBE OF THE HAIR-STREAKSThe Hair-streaks are small butterflies with the eyes notched to allow for the insertion of the bases of the antennae. The name is given on account of the fine, hair-like markings which extend across the under surface of the hind wings. In many species there is a tailed projection or two on the hind inner margin of the hind wing. The caterpillars are remarkable for the small head, so connected with the body that it can be pushed forward in a characteristic way.The Hair-streaks are among the most exquisite and delicate of all our butterflies. A large proportion of them have the upper surface of the wings toned in beautiful hues of grayish brown and the under surface lighter gray, marked with dots and stripes, some of which are brilliant in coloring. A few of the larger species are brilliantly iridescent in purples, blues, and greens, marked with black. The males have well-developed scent-pockets in many species, these being commonly along the front border of the front wing.A very interesting suggestion in regard to the possible function of the curious tail projections was made nearly a hundred years ago by some English entomologists and has since been discussed at considerable length in various publications. It is that the slender tails, together with theenlargement of the wing just back of them, give the impression of a false head. Along with this unusual development of the wing is to be considered the fact that these butterflies nearly always alight head downward so that the false head, furnished with what seem to be waving antennae, takes the place that would naturally be occupied by the true head. Instances have been reported in which this false head has apparently been nipped off by a lizard and much evidence has accumulated to indicate that this curious device may be a real protection in many cases. Of course, the loss of the tails and the part of the wings adjacent would be comparatively insignificant. In most cases, these projections on the wings are held at right angles to the plane of the wing.While nearly half a hundred species of Hair-streaks have been found in North America, only a few of these are sufficiently abundant to require discussion in this little book.The Great Purple Hair-streakAtlides halesusIt seems something of a reflection on the activities of American entomologists to say that, after the lapse of more than a century since Abbott studied the insects of Georgia, our knowledge of the early stages of two of the largest Hair-streak butterflies is still confined to the observations he made. Yet this is true, and one of them—the Great Purple Hair-streak—is the largest species of the group that occurs in the eastern United States. The other is the White-M Hair-streak.The Great Purple Hair-streak is a beautiful, iridescent blue creature, as seen from above, with blackish borders around the blue. As seen from below, the wings are dark brown, with red spots near the body. The two tail-like projections are quite long. It is very large for the group to which it belongs, measuring nearly two inches across the expanded wings. It is a tropical form, extending into our southern borders from California to Florida and occasionally occurring north as far as southern Illinois. The larvae feed on oak. (See plate,page 256.)The White-M Hair-streakEupsyche M-albumThe White-M Hair-streak is about two thirds the size of the Great Purple species with less blue and more black on the upper wing surface. The hind tail is slender and well developed, and the angle of the wing just back of it is rounded out in an unusual fashion. The lower surface of the wing is of a general grayish brown color, marked by a white stripe, which takes the form of the letter M: hence its name. This is also a southern species occurring at times as far north as Ohio and even Atlantic City, New Jersey. The caterpillars feed upon the leaves of oak and Astragalus or milk vetch.There is also a third species of this group of whose history we are ignorant except for Abbot's observations. It is an exquisite little butterfly called the Least Purple Hair-streak (Calycopis cecrops) and is apparently a tropical form which has spread into our Southern states. It is especially beautiful because of the brilliant red andwhite lines running across the under surface of both wings. It occurs as far north as West Virginia and Kentucky and ranges westward at least to the Mississippi Valley.The Gray Hair-streakUranotes melinusThis exquisite little creature is capable of surviving under a great variety of climatic conditions. It ranges from New Hampshire to Florida and Central America, but apparently occurs only rarely north of the United States. Perhaps the most distinctive feature in the female is the orange spot just in front of a pair of tiny tails on each hind wing, the rear one being curiously curved and about three times as long as the other. In the male the shorter tail is absent. The general color of the upper surface is a dark bluish gray, relieved on the margin of each hind wing by a few white dots and the orange spot already mentioned. The under surface is much lighter gray, distinctly marked with two dark brown lines near the margin, the outer line little more than a row of spots and the inner line with a white edge. (See plate,page 257.)These small butterflies lay tiny though beautiful eggs upon a variety of plants. The eggs hatch into curious little caterpillars that have the appearance of slugs with small heads which can be extended as if the little creature had really a rubber neck. The object of this extensile head is seen when one finds the larvae feeding upon the fruits or the seed-pods of its various food plants—hawthorn, hop, hound's-tongue, and St. John's-wort. The caterpillar is able to thrust its jaws into the interior of theseed-pods and devour their contents. There seem to be generally two broods in a season, even in the more northern parts of its range, while toward the south there are probably at least three broods. The butterflies are found upon the wing almost any time in summer, especially from early June until late in August.The Banded Hair-streakThecla calanusThis is one of the most familiar of the delicate little butterflies grouped in the genusThecla. It occurs rather commonly in a great stretch of territory extending from Maine, west to Nebraska, south to New Mexico and Texas, and east to Alabama and Georgia. It also occurs in a limited area on the coast of California. The general color of the upper surface is a dark brown, which in the male is marked near the front edge of the fore wings with a distinct gray patch of scent scales. The under side is similar in color to the upper except that the outer half of the wing is marked by two series of broken lines in white, blue, and brown and a brilliant bit of coloring just in front of the tail projection of the hind wings; this coloring shows beautiful tones of red, blue, and black.These little butterflies may often be seen visiting the midsummer flowers but are fully as likely to be found along the sides of a shady road, where they rest upon the leaves of trees, shrubs, and herbaceous plants. When disturbed, they fly up in small companies but soon settle back again into their previous positions. They are lovers of sunshine and may often be seen upon a leaf, with fully expandedwings, taking a sun-bath. There is but one brood a year, butterflies appearing early in summer and remaining for several weeks. They lay their tiny pale green eggs upon the leaves of various trees, especially oaks and hickories, and probably hawthorns. It is not known whether these eggs remain unhatched as a rule until the following spring, or whether they soon hatch and the young caterpillars hibernate without feeding. It is probable that both conditions occur. In spring the larvae eat holes in the leaves of their food plant and grow rather slowly, gradually becoming brown or green slug-like caterpillars about half an inch long. They finally change into greenish brown chrysalids from which the butterflies emerge in early summer.The Striped Hair-streakThecla liparopsIn the Eastern states the distribution of this species is almost the same as that of the Banded Hair-streak, but in the Central West the outline of its region moves northward extending into Canada, above North Dakota, and into Montana and Wyoming. It does not go so far south, however, extending practically only to the southern borders of Kansas and Missouri. The butterfly bears a striking general resemblance to the other species just named, differing chiefly in the fact that the under surface of the wings is much more thickly marked with broken lines that extend nearer to the body. As a rule, it is not common and consequently it is prized by collectors. Some good observers have noticed that it is more likely to be foundonly on flowers, instead of sunning itself on leaves. It is single-brooded, hibernating either in the egg state or in that of the young larvae. The food plants are varied, there being good evidence that the caterpillar feeds upon all of these: apple, plum, shadbush, blueberry, holly, chestnut, willow, thorn, and several kinds of oaks. Mr. W. F. Fiske found a chrysalis of this species in the deserted nest of a tent caterpillar in New Hampshire in early June, the butterfly emerging later in the month.The Acadian Hair-streakThecla acadicaThis is one of the numerous butterflies that offers some young student an opportunity to make real contributions to science. It is a beautiful little creature, expanding scarcely an inch across its outstretched wings, found from New England west to Montana along a rather restricted area, which coincides pretty closely with the southern part of the Transition Zone. There is a form on the Pacific Coast which is commonly considered to be this same species.These butterflies appear during July and August. They visit various flowers but are especially likely to be found near willow thickets along the borders of brooks and swamps. It is supposed that the eggs are laid upon the willows and that they remain unhatched until the following spring. Then they develop into little caterpillars that feed upon the willow leaves and mature in time to form chrysalids early in June. These chrysalids in turn disclose the butterfly early in July. So far as I know the eggsthemselves and the situation in which they are laid have never been described.The Olive Hair-streakMitoura damonVery few butterflies have the distinction of showing a clear case of protective resemblance to one kind of plant in both the adult and the larval stages. This is the case, however, with this Olive Hair-streak which is so intimately associated with our common red cedar, that where one is found the other is likely to occur, although both caterpillars and butterflies are seldom seen because they resemble the twigs of the cedar so closely.Along the Atlantic Coast this little butterfly occurs from New Hampshire to Florida, and westward to a line drawn from Dakota to Texas. The upper surface of the wings is rather dark olive-brown and the under surface, so far as it is exposed when the butterfly is resting, is of a greenish hue that harmonizes with the green of the red cedar twigs. There are also, on the under surface, some irregular lines and dots of red, brown, and white which probably help in rendering the insect inconspicuous when it is resting among a cluster of twigs.The yearly history of this beautiful little butterfly differs from that of most of its relatives. The species winters in the chrysalis state, the first brood of butterflies bursting forth early in May. These lay their eggs upon or between the scales of the red cedar twigs, especially those which bear flowers. About a week later the eggs hatch into tiny caterpillars that feed upon the scale-like leaves,continuing to eat and grow for nearly six weeks before they reach their full size. These caterpillars are so similar in color that they are difficult to see, and they have a remarkable protective device in that the first ring behind the head is developed into a shield which covers the head, hiding it so completely that the movement of the jaws in feeding is effectively concealed. Late in June they change to chrysalids, part of which appear to remain in this condition until the following spring, while most of them give forth a second brood of butterflies in July. These butterflies lay eggs for a second brood of larvae that mature into chrysalids during September, and hibernate in this condition until the following spring. Consequently, in the Northern states, the collector should look for fresh specimens in May and early June and again in July and early August.These butterflies visit various flowers, apparently preferring rather small blossoms, such as those of the Mouse-ear Everlasting, which is in bloom when the first brood is flying, and the various members of the mint family, especially spearmint, as well as the sumacs, which are in bloom when the second brood is on the wing. The time between flower visits seems to be spent at rest upon the red cedar branches, and one of the surest ways to find the butterflies is to give these trees a sudden jar, which starts them into flight. In fact, they may often be seen flying around the tops of the cedars a score of feet from the ground.Synopsis of the Hair-streaksGreat Purple Hair-streak(Atlides halesusorThecla halesus). Wing expanse 1¾ inches. Upper wing surfacebright blue with blackish margins, the blackish coloring extending nearly to the middle in the female. Two distinct tails on each hind wing. Under surface sepia brown with blue and red spots. Abdomen orange below.White-M Hair-streak(Eupsyche m-albumorThecla m-album). Wing expanse 11⁄3inches. Upper wing surface blue with wide blackish margins in both sexes. Under surface marked with whitish lines suggesting the letter M, with a reddish spot near it. Each hind wing with two small tails.Least Purple Hair-streak(Calycopis cecropsorThecla cecrops). Wing expanse 1 inch or less. Upper wing surface dark brown, more or less marked with blue, especially at base of front wings and inner half of hind wings. Under wing surface marked with a brilliant red line edged outside with white. Two very fine tails on hind wings with brightly colored spots near their base on lower surface.Gray Hair-streak(Uranotes melinusorThecla melinus). Wing expanse 11⁄5inches. Upper wing surface bluish gray with a brilliant red spot at base of tails on hind wing. Lower wing surface much lighter gray, each wing marked with a brown and white stripe and a row of dots nearer the margin.Banded Hair-streak(Thecla calanus). Wing expanse 11⁄5inches. Upper wing surface dull dark brown, commonly without markings although sometimes there is an orange spot on each hind wing. Lower wing surface a little lighter than upper with bright red and blue spots at the base of the tiny tails, and with distinct narrow blue and white broken bands extending across the outer half of each wing.Striped Hair-streak(Thecla liparops). Wing expanse 1 inch. Very similar to the Banded Hair-streak, but having more white markings on the lower surface of the wings.Acadian Hair-streak(Thecla acadica). Wing expanse 11⁄3inches. Upper wing surface blackish brown with a slaty tinge, and red spots at base of the single short tail on each hind wing. Lower surface bluish gray with many small blackish spots edged with white arranged in two principal rows on the outer half of each wing. Larger orange-red spots on each side of base of the tail on each hind wing.Olive Hair-streak(Mitoura damonorThecla damon). Wing expanse 1 inch or less. Upper wing surface olive-brown, more yellow in the male than the female. Tips of tiny tails on hind wing whitish. Lower surface green except where upper wing is covered by lower: this part is brown. The green is marked with a row of white spots on each front wing and two distinct rows of brown and white spots on each hind wing, with black spots between.THE TRIBE OF THE COPPERSThe members of this tribe are well characterized by their name, for most of them show on the upper wing surface tones of coppery brown, more or less marked around the margin with darker shades. On the under side of the tarsi there are numerous spines in irregular clusters. In the chrysalis there are curious hair-like projections on the skin, which are short and shaped like tiny toadstools or mushrooms.While some of the Coppers are very abundant, the majority are rather rare. Only a few species are sufficiently widely distributed to require description here.The WandererFeniseca tarquiniusIn many orders of insects there are whole families whose larvae are habitually carnivorous, feeding entirely upon other kinds of insects. This is especially so in case of the beetles, the flies, the true bugs, and the great order to which the bees and wasps belong. Among the scale-winged insects, however, carnivorous caterpillars are rare, seldom occurring among the moths and in hardly more than one species among the butterflies. This one exception is the modest-looking little butterfly fancifully called the Wanderer, perhaps because instead of frequenting the flowery fields where other butterflies congregate it wanders in and out among the alders by brooks and ponds, alighting oftener upon a leaf or twig than upon a flower—the latter apparently lacking for it the attraction it has for other butterflies.If you watch one of these copper-hued creatures for awhile, however, you will soon see that its wandering is not aimless but has rather a method all its own. Perhaps you will see it alight upon an alder twig on or above which you are likely to notice curious woolly white excrescences. If you are close enough you will probably see the butterfly uncoil its tongue and sip up a liquid on twig or leaf—the exudations of the woolly aphids that make up the supposed excrescence and suck the sap fromthe bark. Much of this sap passes through the bodies of the aphids and collects in liquid globules on twigs and leaves, forming a sort of honey-dew which is much sought after by flies, wasps, and other insects. It seems to form the chief sustenance of these Wanderers.But many of these butterflies have another purpose besides that of sipping the honey-dew. Should you watch one of the mother butterflies carefully you would be likely to see her alight on or near a colony of woolly aphids and run rather rapidly over them in a wasp-like manner, finally stopping long enough to lay a tiny, roundish, slightly flattened egg upon the twig, generally on the under side, and only one in a place. Then she may continue her way, wandering lazily along the alder-bordered stream.Let us now centre our interest upon the egg. Three or four days later it hatches into a curious caterpillar. Instead of having mouth parts fitted for biting leaves as is the case with most butterfly larvae, it has one fitted for grasping, piercing, and sucking the juices of the plump bodies of the aphids, which it finds hard by its place of birth. It also has silk spinnerets connected with its mouth, so it is able to spin a web to shelter it from being run over by its intended victims.The newly hatched larva is not slow to take advantage of the facilities with which it is provided. It at once begins to spin a web above and around itself, from the end of which it reaches out for the nearest aphids, sucking their life-blood and casting their empty skins to the discard of its protecting web. The skins thus serve as an additional shelter so that, as the caterpillar moves forward, increasing the number of its victims from day to day, it extends its web and the protection of the cast skins intermingledwith it, while through all—the cast skins, the silken web, and even the hairs on the body of the caterpillar—there runs a woof of the woolly excretion—effectually concealing the larva from sight.The woolly aphids thus serve as the sole food of the caterpillar during its brief life as a larva. Perhaps because of the pre-digested nature of its food, it is able to mature much sooner than most butterfly larvae. In about eleven days after hatching it is ready to change to a chrysalis, having undergone during this period only three moults, instead of at least four as with other caterpillars. Each caterpillar then changes to a chrysalis which is remarkable because the form and color of its back bears a striking resemblance to the face of a miniature monkey. It remains in this condition nearly a fortnight and then emerges as a butterfly.In New England and the Northern states the short life of the larva enables this insect to mature three broods each season. Farther south there are probably more, for this species is widely distributed in eastern North America, occurring from Nova Scotia to Georgia and west to the Mississippi Valley.The American CopperHeodes hypophlaeasThis little butterfly is one of the most generally abundant insects in the northern part of North America. It commonly occurs from ocean to ocean, from the Hudson Bay region to the latitude of Georgia, and it flies freely in city parks and village yards as well as in the more openspaces of field and forest. When seen through a lens it is very beautifully colored, the coppery red of the wings being overspread with conspicuous black dots and a touch of orange around the outer border. The expanded wings measure just about an inch, so that this is one of the smallest of our common butterflies.The caterpillars of the American Copper feed upon sorrel, one of the commonest weedy plants of waste places everywhere. The rusty red blossoms of the sorrel harmonize in color with the color of the butterfly, which is frequently to be seen flying slowly above the plants, stopping now and then to lay its eggs singly upon the leaves or stems. Each egg soon hatches into a curious caterpillar, which looks more like a slug than the usual type of butterfly larva. It feeds upon the succulent tissue of the sorrel leaf, at first biting small holes in the under surface. As it gets larger it feeds more freely and is likely to make channels instead of holes. It matures in about three weeks, changing into a chrysalis under the shelter of a stone or board. A little later it again changes to a butterfly.There is an interesting variation in the number of broods of this butterfly each season. In regions where it has been studied it has been found to be double-brooded in northern New England and triple-brooded in southern New England and the Atlantic states. It is probable that in its far northern home in the Hudson Bay territory it is only single-brooded. It is thought that the insect hibernates as a chrysalis.These little butterflies are so small and fly so near the ground that they are likely to be overlooked by the casual observer. They frequently alight to sun themselves or to sip nectar from many kinds of flowers. They begin their day's work early in the morning and continue well into the evening. Then they find a roosting-place, head downward upon a blade of grass, where they sleep until wakened by the morning sunshine.From a drawing by W. I. BeecroftFIVE INTERESTING BUTTERFLIESThe Spring Azure (p. 258) at the top; the Falcate Orange-Tip (p. 94) next; the Bronze Copper (p. 257), female, next; the Spring Azure (p. 258) resting on a leaf, next; and the Great Purple Hair-streak (p. 243), female, below.Seepage 245STAGES OF THE GRAY HAIR-STREAKThe Bronze CopperChrysophanus thoeThis butterfly is nearly twice as large as the American Copper to which the female of the present species bears a striking resemblance. The Bronze Copper is a rare species, occurring from New England nearly to the Rocky Mountains. The slug-shaped yellowish green caterpillar feeds upon dock and related plants. (See plate,page 256.)Synopsis of the CoppersThe Wanderer(Feniseca tarquinius). Wing expanse 1¼ inches. Upper wing surface tawny brown, each wing more or less marked with dark brown spots, the distinction between the colors being clear-cut, and the lines between having an angular effect. Lower surface of front wings similar in colors to upper with dark spots rectangular. Under surface of hind wings mottled with irregular spots of pale brown.American Copper(Heodes hypophlaeasorChrysophanus hypophlaeas). Wing expanse 1 inch. Upper surface of front wings tawny orange with margins and rectangular spots blackish. Upper surface of hind wings coppery red with a tawny orange band on outer margin. Lower surface of front wings much like upper surface; that of hindwings grayish marked with dark spots and an orange line near the margin.Bronze Copper(Chrysophanus thoe). Wing expanse 1½ inches.Male.Upper wing surface coppery brown marked with dark spots and a tawny orange sub-marginal band along outer margin of hind wings. Under surface of front wings lighter orange with blackish spots and of hind wings grayish with blackish spots and an orange sub-marginal band.Female.Upper surface of front wings tawny orange with blackish spots.THE TRIBE OF THE BLUESThese beautiful little butterflies are well named, for the majority of them are colored in exquisite tints of blue. They are distinguished from the Coppers by this blue coloring, as well as by the fact that the spines on the under side of the tarsi are arranged in rows rather than in clusters and are comparatively few in number. The body is rather slender and the under surfaces of the wings are generally dotted in a characteristic fashion. Most of the two score or more species found in North America occur on the Pacific Coast or in the Southwest, less than half a dozen being common in the eastern region.The Spring AzureCyaniris ladonFor a wee bit of a gossamer-winged creature that expands scarcely an inch across its outstretched wings, theSpring Azure has caused American scientists an immense amount of patient labor. Over the vast territory from Labrador across to Alaska and south to the Gulf of Mexico, this little blue butterfly exists in so many different forms that it requires special analytical keys to separate them. Not only does it vary geographically so that in one locality we find one form and in another a different form, but it also varies seasonally to a marked degree. As one would expect there is a striking difference in its annual cycle between Labrador and the Gulf Coast. In the far northern region there is but one brood a year, while in the southern region there are at least two and perhaps more.The variations in this butterfly are shown by the differences in the marking of both surfaces of the wings. These markings may run from a faint blackish border along the extreme margin and a few faint dots upon the under surface, to a wide black margin around the wings and a deep abundant spotting of the under surface. The markings of the various forms are so uniform that the varieties are easily distinguished. It is beyond the scope of this book to attempt to differentiate all these varieties but any reader interested will find an admirable summary of the conditions illustrated by an excellent plate in Comstock's "How to Know the Butterflies." The species as a whole may be known from the fact that the upper surface is blue, the lower surface ash-gray, more or less spotted with dark brown, and the wings are without tails. (See plate,page 256.)The Strange Structures of the LarvaeA remarkable variation of the adults is sufficient to give this species a special interest, but the larvae also have a unique attraction for the naturalist. The mother butterflieslay their eggs upon the flower buds of various plants, especially those which have clustered racemes of blossoms. These eggs hatch into minute slug-like larvae which feed upon the buds, commonly burrowing through the calyx lobes and devouring the undeveloped stamens and pistils inside. They finally change to chrysalids, which are more or less securely attached to a central flower stalk, from which in due time the butterflies emerge. So far there is nothing remarkable about this story of the life of the Spring Azure, but that is yet to come.These little caterpillars are subject to attack by tiny parasitic flies which lay eggs in their bodies. Each egg hatches into a still more tiny maggot that lives at the expense of the tissues of the caterpillar and finally kills it. When one of these little caterpillars has its head buried in the round ball of a flower bud, about half of its body is exposed defenseless, so that the little fly that lights upon it to lay her egg cannot even be dislodged by the head of the caterpillar, as is often the case with other species. There is a very curious provision for defense, however. If you look carefully through a lens at the hind part of the body you will find a little opening on the back of the seventh abdominal ring. This opening leads to a sort of tiny pocket, a pocket which the caterpillar can turn inside out when it so desires. Now the curious thing about it is that the caterpillar, while this pocket is concealed in its body, is able to secrete in it a drop of liquid which we presume to be sweet to the taste. When the little pocket is partly filled with this drop of liquid the caterpillar turns it inside out in such a way that the liquid drop remains in position on top of the protruded pocket.Perhaps you ask what is the good of all this complicatedarrangement? If you could see what happens when the little drop of what—for lack of a better name—we shall call honey-dew is exposed, you would begin to guess the reason. Wherever these larvae are found you will also find many ants wandering round among them, and the moment the honey-dew appears these ants begin to sip it up. When it is all gone the little caterpillar draws in its pocket again and presumably begins to store up another bit of liquid. It is certainly a curious example of what the naturalists call symbiosis, which simply means a living together of two animals, each helping the other in some way. In this case it is easy enough to see how the caterpillar helps the ant, but perhaps you are wondering in what possible way the ant may help the caterpillar. I hardly dare give the most plausible explanation for fear some one will cry out, "Nature-faker!" But fortunately the explanation is based upon at least one precise observation by W. H. Edwards, one of the most careful and reliable naturalists America has produced, who lived before the recent era of Nature-fakers and was never accused of sensationalism. Mr. Edwards saw an ant drive away from one of these caterpillars a little parasitic fly which apparently was searching for a victim. Consequently, it would appear that the ants helped the caterpillars by protecting them from these arch enemies.This is by no means an isolated example of the relations between ants and other insects. It has been known for hundreds of years that the ants use the aphids as a sort of domestic milk-producer, attending the aphids at all times and even caring for their eggs throughout the winter season. As the plant-lice live in colonies, sucking the sap of their host plant, they are attended by great numbers ofants that feed upon the honey-dew which passes through their bodies. In many cases the ants have been observed to stroke the aphids with their antennae in a way which seems to induce the aphid to give out a drop of the sweet liquid for the ant to lap up. In a similar way these ants seem sometimes to stroke these little caterpillars with their antennae and thus to induce them to turn their little pockets inside out with the drop of liquid at the tip. This is certainly an unusual and most interesting relation between two insects far separated by their structural characters.The little pocket that I have thus described is situated upon the seventh segment of the abdomen. Just back of it there are two other openings which are even more curious in their structure. These are provided with some slender tentacles on which there are circles of hairy spurs. These structures are a great puzzle to naturalists. It is difficult to explain what they are for unless we assume that they relate in some way to the honey-dew pocket on the seventh ring. The only plausible explanation is that these serve to advertise to the ants, by giving off a distinctive odor, that there is nectar near at hand to be had for the asking. They would thus beanalogousin a way to the fragrant scent of flowers which is for the purpose of advertising to the bee the fact that nectar or pollen or both are near at hand and may be had for the asking. In the case of these caterpillars, however, if this is the true explanation it is a most wonderful provision and one which would be likely to tax the ingenuity of man's mind for a long while before it was originated.So this little butterfly which greets us in every spring, like "a violet afloat," to quote Mr. Scudder's happy phrase,is full of interest at all stages of its existence. It should lead one to a new respect for the familiar things in the natural world when one learns how baffling to the wits of the wisest scientist is this little creature with its protean forms and the wonderful structure of its caterpillars.Scudder's BlueRusticus scudderiThis beautiful little butterfly is perhaps the most richly colored of all our northern Blues. The upper surface of the wings in the male is a nearly uniform hue, except for a narrow dark border around the margin. In the female there is, in addition, a series of black-centred orange spots inside of the black border, the series being more prominent on the hind wings than on the front ones. The under surface is very pale with distinct marks in black scattered over the basal two thirds, with a row of orange spots outside of these and another row of small blackish spots just inside of the blackish border stripe.This butterfly is a northern species. It occurs in New England, New York, and Michigan, and thence extends far north into Canada. The caterpillar feeds upon blue lupine and apparently the butterfly is likely to be found in most places where this plant grows. The eggs are laid upon the leaves or stems and the little caterpillars come out of the shells through small holes which they have gnawed."The caterpillar," wrote Mr. Scudder, "has a very extensible head and flexible neck, and its manner of feedingimmediately after birth is rather remarkable; it pierces the lower cuticle of the leaf, making a hole just large enough to introduce its minute head, and then devours all the interior of the leaf as far as it can reach—many times the diameter of the hole—so that when the caterpillar goes elsewhere, the leaf looks as if marked with a circular blister, having a central nucleus; the nearly colorless membranes of the leaf being all that is left, and at the central entrance to the blister the upper membrane only." Later in its life it often modifies this feeding habit somewhat, and as it approaches full growth it is likely to devour the entire blade of the leaf.These larvae have the curious nectar-secreting glands on the seventh abdominal segment which are discussed in connection with the preceding species. Many ants are attracted by this secretion so that it often happens that the easiest way to find the caterpillars is to look for these attendants. In New England there are two broods of the butterfly, one appearing early in June and the other late in July.
THE METAL-MARKS
FamilyRiodinidae
This small family of very small butterflies contains five genera and a dozen species found in the United States and Mexico. Only two, however, occur in the eastern region and only one extends much north of the Gulf states. Aside from certain peculiarities of the wing-venation (acostal and a humeral vein on the hind wings) these Metal-marks may be known by their minuteness and the bright metallic markings on the brown wings.
Both our eastern species belong to the genusCalephelis. The Small Metal-mark (C. caenius) has been collected in Florida and Georgia. The wings are rusty red on both surfaces, brighter below than above, and marked with blackish spots that almost converge to form stripes; in addition to which there are, beyond the middle of each wing, two lines made by special scales that glisten with a steel glitter. The wings expand only about three quarters of an inch. So far as I can learn, the egg, larva, or pupa have never been described.
The Large Metal-mark is called by scienceCalephelis borealis, but it deserves the latter name only in the sense that it is more northern than its allies. It has been collected as far north as New York and Michigan, but it seems to be very seldom found, at least in eastern regions. It expands a little more than an inch. The general color of the wings is yellowish brown, marked with blackish dots and lines, together with rows of steely spots on the under surface. In this case also the life-history is unknown.
Seepage 236THE SNOUT BUTTERFLY IN FLIGHT AND AT REST
Seepage 236THE SNOUT BUTTERFLY IN FLIGHT AND AT REST
Seepage 236
Seepage 62GIANT SWALLOWTAIL JUST OUT OF THE CHRYSALIS
Seepage 62GIANT SWALLOWTAIL JUST OUT OF THE CHRYSALIS
Seepage 62
From a drawing by W. I. BeecroftSeepage 233THE MONARCH BUTTERFLYCaterpillar feeding; caterpillar hung up for pupation; chrysalis, and adult
From a drawing by W. I. BeecroftSeepage 233THE MONARCH BUTTERFLYCaterpillar feeding; caterpillar hung up for pupation; chrysalis, and adult
From a drawing by W. I. Beecroft
Seepage 233
THE GOSSAMER-WINGS
FamilyLycaenidae
The daintiest and most delicate of all our butterflies are included among the Gossamer-wings. Their bodies are small and slender, their antennae ringed with white and almost threadlike, their wings thin and of exquisite beauty. Many of them are marked with the slenderest of tailed projections from the hind wings. When the face is viewed from in front it is seen to be much narrower than its height. At the insertion of the antennae the eyes are notched, and they are also more or less surrounded with white scales. Most of the caterpillars have oval, slug-shaped, smooth bodies, with the under surface flattened, and very small heads, which in many species can be extended by means of an extensile neck. The chrysalids are held in place by silken threads both at the tail and over the middle. They are rounded, short, and stout.
Notwithstanding their small size, the Gossamer-wings are among the most spritely of all our butterflies. They seem indeed winged sprites, playing everywhere, in fields and open woods, along roads, lanes, and brooks, in door-yards and gardens—wherever, in fact, a bit of open space invites their presence. Not alone upon the wing but even when at rest does their liveliness appear. For most of these butterflies have the curious habit of keeping the hind wings in motion after alighting, rubbing them against each other in a vertical plane or "moving them backward and forward when half expanded." These habits are so fixed that when one sees a butterfly thus engaged one can pretty certainly conclude it is a member of this family.
The Gossamer-wings are commonly separated into three rather distinct tribes—the Hair-streaks, the Coppers, and the Blues. The characteristic features are these:
Three branches arising from the radius of each front wing. Under surface of hind wing commonly marked with threadlike streaks: the Hair-streaks.
Four branches arising from the radius of each frontwing. Under surface of hind wing commonly marked with spots rather than lines.
Colors brownish red: The Coppers.
Colors blue: The Blues.
THE TRIBE OF THE HAIR-STREAKS
The Hair-streaks are small butterflies with the eyes notched to allow for the insertion of the bases of the antennae. The name is given on account of the fine, hair-like markings which extend across the under surface of the hind wings. In many species there is a tailed projection or two on the hind inner margin of the hind wing. The caterpillars are remarkable for the small head, so connected with the body that it can be pushed forward in a characteristic way.
The Hair-streaks are among the most exquisite and delicate of all our butterflies. A large proportion of them have the upper surface of the wings toned in beautiful hues of grayish brown and the under surface lighter gray, marked with dots and stripes, some of which are brilliant in coloring. A few of the larger species are brilliantly iridescent in purples, blues, and greens, marked with black. The males have well-developed scent-pockets in many species, these being commonly along the front border of the front wing.
A very interesting suggestion in regard to the possible function of the curious tail projections was made nearly a hundred years ago by some English entomologists and has since been discussed at considerable length in various publications. It is that the slender tails, together with theenlargement of the wing just back of them, give the impression of a false head. Along with this unusual development of the wing is to be considered the fact that these butterflies nearly always alight head downward so that the false head, furnished with what seem to be waving antennae, takes the place that would naturally be occupied by the true head. Instances have been reported in which this false head has apparently been nipped off by a lizard and much evidence has accumulated to indicate that this curious device may be a real protection in many cases. Of course, the loss of the tails and the part of the wings adjacent would be comparatively insignificant. In most cases, these projections on the wings are held at right angles to the plane of the wing.
While nearly half a hundred species of Hair-streaks have been found in North America, only a few of these are sufficiently abundant to require discussion in this little book.
The Great Purple Hair-streakAtlides halesus
It seems something of a reflection on the activities of American entomologists to say that, after the lapse of more than a century since Abbott studied the insects of Georgia, our knowledge of the early stages of two of the largest Hair-streak butterflies is still confined to the observations he made. Yet this is true, and one of them—the Great Purple Hair-streak—is the largest species of the group that occurs in the eastern United States. The other is the White-M Hair-streak.
The Great Purple Hair-streak is a beautiful, iridescent blue creature, as seen from above, with blackish borders around the blue. As seen from below, the wings are dark brown, with red spots near the body. The two tail-like projections are quite long. It is very large for the group to which it belongs, measuring nearly two inches across the expanded wings. It is a tropical form, extending into our southern borders from California to Florida and occasionally occurring north as far as southern Illinois. The larvae feed on oak. (See plate,page 256.)
The White-M Hair-streakEupsyche M-album
The White-M Hair-streak is about two thirds the size of the Great Purple species with less blue and more black on the upper wing surface. The hind tail is slender and well developed, and the angle of the wing just back of it is rounded out in an unusual fashion. The lower surface of the wing is of a general grayish brown color, marked by a white stripe, which takes the form of the letter M: hence its name. This is also a southern species occurring at times as far north as Ohio and even Atlantic City, New Jersey. The caterpillars feed upon the leaves of oak and Astragalus or milk vetch.
There is also a third species of this group of whose history we are ignorant except for Abbot's observations. It is an exquisite little butterfly called the Least Purple Hair-streak (Calycopis cecrops) and is apparently a tropical form which has spread into our Southern states. It is especially beautiful because of the brilliant red andwhite lines running across the under surface of both wings. It occurs as far north as West Virginia and Kentucky and ranges westward at least to the Mississippi Valley.
The Gray Hair-streakUranotes melinus
This exquisite little creature is capable of surviving under a great variety of climatic conditions. It ranges from New Hampshire to Florida and Central America, but apparently occurs only rarely north of the United States. Perhaps the most distinctive feature in the female is the orange spot just in front of a pair of tiny tails on each hind wing, the rear one being curiously curved and about three times as long as the other. In the male the shorter tail is absent. The general color of the upper surface is a dark bluish gray, relieved on the margin of each hind wing by a few white dots and the orange spot already mentioned. The under surface is much lighter gray, distinctly marked with two dark brown lines near the margin, the outer line little more than a row of spots and the inner line with a white edge. (See plate,page 257.)
These small butterflies lay tiny though beautiful eggs upon a variety of plants. The eggs hatch into curious little caterpillars that have the appearance of slugs with small heads which can be extended as if the little creature had really a rubber neck. The object of this extensile head is seen when one finds the larvae feeding upon the fruits or the seed-pods of its various food plants—hawthorn, hop, hound's-tongue, and St. John's-wort. The caterpillar is able to thrust its jaws into the interior of theseed-pods and devour their contents. There seem to be generally two broods in a season, even in the more northern parts of its range, while toward the south there are probably at least three broods. The butterflies are found upon the wing almost any time in summer, especially from early June until late in August.
The Banded Hair-streakThecla calanus
This is one of the most familiar of the delicate little butterflies grouped in the genusThecla. It occurs rather commonly in a great stretch of territory extending from Maine, west to Nebraska, south to New Mexico and Texas, and east to Alabama and Georgia. It also occurs in a limited area on the coast of California. The general color of the upper surface is a dark brown, which in the male is marked near the front edge of the fore wings with a distinct gray patch of scent scales. The under side is similar in color to the upper except that the outer half of the wing is marked by two series of broken lines in white, blue, and brown and a brilliant bit of coloring just in front of the tail projection of the hind wings; this coloring shows beautiful tones of red, blue, and black.
These little butterflies may often be seen visiting the midsummer flowers but are fully as likely to be found along the sides of a shady road, where they rest upon the leaves of trees, shrubs, and herbaceous plants. When disturbed, they fly up in small companies but soon settle back again into their previous positions. They are lovers of sunshine and may often be seen upon a leaf, with fully expandedwings, taking a sun-bath. There is but one brood a year, butterflies appearing early in summer and remaining for several weeks. They lay their tiny pale green eggs upon the leaves of various trees, especially oaks and hickories, and probably hawthorns. It is not known whether these eggs remain unhatched as a rule until the following spring, or whether they soon hatch and the young caterpillars hibernate without feeding. It is probable that both conditions occur. In spring the larvae eat holes in the leaves of their food plant and grow rather slowly, gradually becoming brown or green slug-like caterpillars about half an inch long. They finally change into greenish brown chrysalids from which the butterflies emerge in early summer.
The Striped Hair-streakThecla liparops
In the Eastern states the distribution of this species is almost the same as that of the Banded Hair-streak, but in the Central West the outline of its region moves northward extending into Canada, above North Dakota, and into Montana and Wyoming. It does not go so far south, however, extending practically only to the southern borders of Kansas and Missouri. The butterfly bears a striking general resemblance to the other species just named, differing chiefly in the fact that the under surface of the wings is much more thickly marked with broken lines that extend nearer to the body. As a rule, it is not common and consequently it is prized by collectors. Some good observers have noticed that it is more likely to be foundonly on flowers, instead of sunning itself on leaves. It is single-brooded, hibernating either in the egg state or in that of the young larvae. The food plants are varied, there being good evidence that the caterpillar feeds upon all of these: apple, plum, shadbush, blueberry, holly, chestnut, willow, thorn, and several kinds of oaks. Mr. W. F. Fiske found a chrysalis of this species in the deserted nest of a tent caterpillar in New Hampshire in early June, the butterfly emerging later in the month.
The Acadian Hair-streakThecla acadica
This is one of the numerous butterflies that offers some young student an opportunity to make real contributions to science. It is a beautiful little creature, expanding scarcely an inch across its outstretched wings, found from New England west to Montana along a rather restricted area, which coincides pretty closely with the southern part of the Transition Zone. There is a form on the Pacific Coast which is commonly considered to be this same species.
These butterflies appear during July and August. They visit various flowers but are especially likely to be found near willow thickets along the borders of brooks and swamps. It is supposed that the eggs are laid upon the willows and that they remain unhatched until the following spring. Then they develop into little caterpillars that feed upon the willow leaves and mature in time to form chrysalids early in June. These chrysalids in turn disclose the butterfly early in July. So far as I know the eggsthemselves and the situation in which they are laid have never been described.
The Olive Hair-streakMitoura damon
Very few butterflies have the distinction of showing a clear case of protective resemblance to one kind of plant in both the adult and the larval stages. This is the case, however, with this Olive Hair-streak which is so intimately associated with our common red cedar, that where one is found the other is likely to occur, although both caterpillars and butterflies are seldom seen because they resemble the twigs of the cedar so closely.
Along the Atlantic Coast this little butterfly occurs from New Hampshire to Florida, and westward to a line drawn from Dakota to Texas. The upper surface of the wings is rather dark olive-brown and the under surface, so far as it is exposed when the butterfly is resting, is of a greenish hue that harmonizes with the green of the red cedar twigs. There are also, on the under surface, some irregular lines and dots of red, brown, and white which probably help in rendering the insect inconspicuous when it is resting among a cluster of twigs.
The yearly history of this beautiful little butterfly differs from that of most of its relatives. The species winters in the chrysalis state, the first brood of butterflies bursting forth early in May. These lay their eggs upon or between the scales of the red cedar twigs, especially those which bear flowers. About a week later the eggs hatch into tiny caterpillars that feed upon the scale-like leaves,continuing to eat and grow for nearly six weeks before they reach their full size. These caterpillars are so similar in color that they are difficult to see, and they have a remarkable protective device in that the first ring behind the head is developed into a shield which covers the head, hiding it so completely that the movement of the jaws in feeding is effectively concealed. Late in June they change to chrysalids, part of which appear to remain in this condition until the following spring, while most of them give forth a second brood of butterflies in July. These butterflies lay eggs for a second brood of larvae that mature into chrysalids during September, and hibernate in this condition until the following spring. Consequently, in the Northern states, the collector should look for fresh specimens in May and early June and again in July and early August.
These butterflies visit various flowers, apparently preferring rather small blossoms, such as those of the Mouse-ear Everlasting, which is in bloom when the first brood is flying, and the various members of the mint family, especially spearmint, as well as the sumacs, which are in bloom when the second brood is on the wing. The time between flower visits seems to be spent at rest upon the red cedar branches, and one of the surest ways to find the butterflies is to give these trees a sudden jar, which starts them into flight. In fact, they may often be seen flying around the tops of the cedars a score of feet from the ground.
Synopsis of the Hair-streaks
Great Purple Hair-streak(Atlides halesusorThecla halesus). Wing expanse 1¾ inches. Upper wing surfacebright blue with blackish margins, the blackish coloring extending nearly to the middle in the female. Two distinct tails on each hind wing. Under surface sepia brown with blue and red spots. Abdomen orange below.
White-M Hair-streak(Eupsyche m-albumorThecla m-album). Wing expanse 11⁄3inches. Upper wing surface blue with wide blackish margins in both sexes. Under surface marked with whitish lines suggesting the letter M, with a reddish spot near it. Each hind wing with two small tails.
Least Purple Hair-streak(Calycopis cecropsorThecla cecrops). Wing expanse 1 inch or less. Upper wing surface dark brown, more or less marked with blue, especially at base of front wings and inner half of hind wings. Under wing surface marked with a brilliant red line edged outside with white. Two very fine tails on hind wings with brightly colored spots near their base on lower surface.
Gray Hair-streak(Uranotes melinusorThecla melinus). Wing expanse 11⁄5inches. Upper wing surface bluish gray with a brilliant red spot at base of tails on hind wing. Lower wing surface much lighter gray, each wing marked with a brown and white stripe and a row of dots nearer the margin.
Banded Hair-streak(Thecla calanus). Wing expanse 11⁄5inches. Upper wing surface dull dark brown, commonly without markings although sometimes there is an orange spot on each hind wing. Lower wing surface a little lighter than upper with bright red and blue spots at the base of the tiny tails, and with distinct narrow blue and white broken bands extending across the outer half of each wing.
Striped Hair-streak(Thecla liparops). Wing expanse 1 inch. Very similar to the Banded Hair-streak, but having more white markings on the lower surface of the wings.
Acadian Hair-streak(Thecla acadica). Wing expanse 11⁄3inches. Upper wing surface blackish brown with a slaty tinge, and red spots at base of the single short tail on each hind wing. Lower surface bluish gray with many small blackish spots edged with white arranged in two principal rows on the outer half of each wing. Larger orange-red spots on each side of base of the tail on each hind wing.
Olive Hair-streak(Mitoura damonorThecla damon). Wing expanse 1 inch or less. Upper wing surface olive-brown, more yellow in the male than the female. Tips of tiny tails on hind wing whitish. Lower surface green except where upper wing is covered by lower: this part is brown. The green is marked with a row of white spots on each front wing and two distinct rows of brown and white spots on each hind wing, with black spots between.
THE TRIBE OF THE COPPERS
The members of this tribe are well characterized by their name, for most of them show on the upper wing surface tones of coppery brown, more or less marked around the margin with darker shades. On the under side of the tarsi there are numerous spines in irregular clusters. In the chrysalis there are curious hair-like projections on the skin, which are short and shaped like tiny toadstools or mushrooms.
While some of the Coppers are very abundant, the majority are rather rare. Only a few species are sufficiently widely distributed to require description here.
The WandererFeniseca tarquinius
In many orders of insects there are whole families whose larvae are habitually carnivorous, feeding entirely upon other kinds of insects. This is especially so in case of the beetles, the flies, the true bugs, and the great order to which the bees and wasps belong. Among the scale-winged insects, however, carnivorous caterpillars are rare, seldom occurring among the moths and in hardly more than one species among the butterflies. This one exception is the modest-looking little butterfly fancifully called the Wanderer, perhaps because instead of frequenting the flowery fields where other butterflies congregate it wanders in and out among the alders by brooks and ponds, alighting oftener upon a leaf or twig than upon a flower—the latter apparently lacking for it the attraction it has for other butterflies.
If you watch one of these copper-hued creatures for awhile, however, you will soon see that its wandering is not aimless but has rather a method all its own. Perhaps you will see it alight upon an alder twig on or above which you are likely to notice curious woolly white excrescences. If you are close enough you will probably see the butterfly uncoil its tongue and sip up a liquid on twig or leaf—the exudations of the woolly aphids that make up the supposed excrescence and suck the sap fromthe bark. Much of this sap passes through the bodies of the aphids and collects in liquid globules on twigs and leaves, forming a sort of honey-dew which is much sought after by flies, wasps, and other insects. It seems to form the chief sustenance of these Wanderers.
But many of these butterflies have another purpose besides that of sipping the honey-dew. Should you watch one of the mother butterflies carefully you would be likely to see her alight on or near a colony of woolly aphids and run rather rapidly over them in a wasp-like manner, finally stopping long enough to lay a tiny, roundish, slightly flattened egg upon the twig, generally on the under side, and only one in a place. Then she may continue her way, wandering lazily along the alder-bordered stream.
Let us now centre our interest upon the egg. Three or four days later it hatches into a curious caterpillar. Instead of having mouth parts fitted for biting leaves as is the case with most butterfly larvae, it has one fitted for grasping, piercing, and sucking the juices of the plump bodies of the aphids, which it finds hard by its place of birth. It also has silk spinnerets connected with its mouth, so it is able to spin a web to shelter it from being run over by its intended victims.
The newly hatched larva is not slow to take advantage of the facilities with which it is provided. It at once begins to spin a web above and around itself, from the end of which it reaches out for the nearest aphids, sucking their life-blood and casting their empty skins to the discard of its protecting web. The skins thus serve as an additional shelter so that, as the caterpillar moves forward, increasing the number of its victims from day to day, it extends its web and the protection of the cast skins intermingledwith it, while through all—the cast skins, the silken web, and even the hairs on the body of the caterpillar—there runs a woof of the woolly excretion—effectually concealing the larva from sight.
The woolly aphids thus serve as the sole food of the caterpillar during its brief life as a larva. Perhaps because of the pre-digested nature of its food, it is able to mature much sooner than most butterfly larvae. In about eleven days after hatching it is ready to change to a chrysalis, having undergone during this period only three moults, instead of at least four as with other caterpillars. Each caterpillar then changes to a chrysalis which is remarkable because the form and color of its back bears a striking resemblance to the face of a miniature monkey. It remains in this condition nearly a fortnight and then emerges as a butterfly.
In New England and the Northern states the short life of the larva enables this insect to mature three broods each season. Farther south there are probably more, for this species is widely distributed in eastern North America, occurring from Nova Scotia to Georgia and west to the Mississippi Valley.
The American CopperHeodes hypophlaeas
This little butterfly is one of the most generally abundant insects in the northern part of North America. It commonly occurs from ocean to ocean, from the Hudson Bay region to the latitude of Georgia, and it flies freely in city parks and village yards as well as in the more openspaces of field and forest. When seen through a lens it is very beautifully colored, the coppery red of the wings being overspread with conspicuous black dots and a touch of orange around the outer border. The expanded wings measure just about an inch, so that this is one of the smallest of our common butterflies.
The caterpillars of the American Copper feed upon sorrel, one of the commonest weedy plants of waste places everywhere. The rusty red blossoms of the sorrel harmonize in color with the color of the butterfly, which is frequently to be seen flying slowly above the plants, stopping now and then to lay its eggs singly upon the leaves or stems. Each egg soon hatches into a curious caterpillar, which looks more like a slug than the usual type of butterfly larva. It feeds upon the succulent tissue of the sorrel leaf, at first biting small holes in the under surface. As it gets larger it feeds more freely and is likely to make channels instead of holes. It matures in about three weeks, changing into a chrysalis under the shelter of a stone or board. A little later it again changes to a butterfly.
There is an interesting variation in the number of broods of this butterfly each season. In regions where it has been studied it has been found to be double-brooded in northern New England and triple-brooded in southern New England and the Atlantic states. It is probable that in its far northern home in the Hudson Bay territory it is only single-brooded. It is thought that the insect hibernates as a chrysalis.
These little butterflies are so small and fly so near the ground that they are likely to be overlooked by the casual observer. They frequently alight to sun themselves or to sip nectar from many kinds of flowers. They begin their day's work early in the morning and continue well into the evening. Then they find a roosting-place, head downward upon a blade of grass, where they sleep until wakened by the morning sunshine.
From a drawing by W. I. BeecroftFIVE INTERESTING BUTTERFLIESThe Spring Azure (p. 258) at the top; the Falcate Orange-Tip (p. 94) next; the Bronze Copper (p. 257), female, next; the Spring Azure (p. 258) resting on a leaf, next; and the Great Purple Hair-streak (p. 243), female, below.
From a drawing by W. I. BeecroftFIVE INTERESTING BUTTERFLIESThe Spring Azure (p. 258) at the top; the Falcate Orange-Tip (p. 94) next; the Bronze Copper (p. 257), female, next; the Spring Azure (p. 258) resting on a leaf, next; and the Great Purple Hair-streak (p. 243), female, below.
From a drawing by W. I. Beecroft
The Spring Azure (p. 258) at the top; the Falcate Orange-Tip (p. 94) next; the Bronze Copper (p. 257), female, next; the Spring Azure (p. 258) resting on a leaf, next; and the Great Purple Hair-streak (p. 243), female, below.
Seepage 245STAGES OF THE GRAY HAIR-STREAK
Seepage 245STAGES OF THE GRAY HAIR-STREAK
Seepage 245
The Bronze CopperChrysophanus thoe
This butterfly is nearly twice as large as the American Copper to which the female of the present species bears a striking resemblance. The Bronze Copper is a rare species, occurring from New England nearly to the Rocky Mountains. The slug-shaped yellowish green caterpillar feeds upon dock and related plants. (See plate,page 256.)
Synopsis of the Coppers
The Wanderer(Feniseca tarquinius). Wing expanse 1¼ inches. Upper wing surface tawny brown, each wing more or less marked with dark brown spots, the distinction between the colors being clear-cut, and the lines between having an angular effect. Lower surface of front wings similar in colors to upper with dark spots rectangular. Under surface of hind wings mottled with irregular spots of pale brown.
American Copper(Heodes hypophlaeasorChrysophanus hypophlaeas). Wing expanse 1 inch. Upper surface of front wings tawny orange with margins and rectangular spots blackish. Upper surface of hind wings coppery red with a tawny orange band on outer margin. Lower surface of front wings much like upper surface; that of hindwings grayish marked with dark spots and an orange line near the margin.
Bronze Copper(Chrysophanus thoe). Wing expanse 1½ inches.Male.Upper wing surface coppery brown marked with dark spots and a tawny orange sub-marginal band along outer margin of hind wings. Under surface of front wings lighter orange with blackish spots and of hind wings grayish with blackish spots and an orange sub-marginal band.Female.Upper surface of front wings tawny orange with blackish spots.
THE TRIBE OF THE BLUES
These beautiful little butterflies are well named, for the majority of them are colored in exquisite tints of blue. They are distinguished from the Coppers by this blue coloring, as well as by the fact that the spines on the under side of the tarsi are arranged in rows rather than in clusters and are comparatively few in number. The body is rather slender and the under surfaces of the wings are generally dotted in a characteristic fashion. Most of the two score or more species found in North America occur on the Pacific Coast or in the Southwest, less than half a dozen being common in the eastern region.
The Spring AzureCyaniris ladon
For a wee bit of a gossamer-winged creature that expands scarcely an inch across its outstretched wings, theSpring Azure has caused American scientists an immense amount of patient labor. Over the vast territory from Labrador across to Alaska and south to the Gulf of Mexico, this little blue butterfly exists in so many different forms that it requires special analytical keys to separate them. Not only does it vary geographically so that in one locality we find one form and in another a different form, but it also varies seasonally to a marked degree. As one would expect there is a striking difference in its annual cycle between Labrador and the Gulf Coast. In the far northern region there is but one brood a year, while in the southern region there are at least two and perhaps more.
The variations in this butterfly are shown by the differences in the marking of both surfaces of the wings. These markings may run from a faint blackish border along the extreme margin and a few faint dots upon the under surface, to a wide black margin around the wings and a deep abundant spotting of the under surface. The markings of the various forms are so uniform that the varieties are easily distinguished. It is beyond the scope of this book to attempt to differentiate all these varieties but any reader interested will find an admirable summary of the conditions illustrated by an excellent plate in Comstock's "How to Know the Butterflies." The species as a whole may be known from the fact that the upper surface is blue, the lower surface ash-gray, more or less spotted with dark brown, and the wings are without tails. (See plate,page 256.)
The Strange Structures of the Larvae
A remarkable variation of the adults is sufficient to give this species a special interest, but the larvae also have a unique attraction for the naturalist. The mother butterflieslay their eggs upon the flower buds of various plants, especially those which have clustered racemes of blossoms. These eggs hatch into minute slug-like larvae which feed upon the buds, commonly burrowing through the calyx lobes and devouring the undeveloped stamens and pistils inside. They finally change to chrysalids, which are more or less securely attached to a central flower stalk, from which in due time the butterflies emerge. So far there is nothing remarkable about this story of the life of the Spring Azure, but that is yet to come.
These little caterpillars are subject to attack by tiny parasitic flies which lay eggs in their bodies. Each egg hatches into a still more tiny maggot that lives at the expense of the tissues of the caterpillar and finally kills it. When one of these little caterpillars has its head buried in the round ball of a flower bud, about half of its body is exposed defenseless, so that the little fly that lights upon it to lay her egg cannot even be dislodged by the head of the caterpillar, as is often the case with other species. There is a very curious provision for defense, however. If you look carefully through a lens at the hind part of the body you will find a little opening on the back of the seventh abdominal ring. This opening leads to a sort of tiny pocket, a pocket which the caterpillar can turn inside out when it so desires. Now the curious thing about it is that the caterpillar, while this pocket is concealed in its body, is able to secrete in it a drop of liquid which we presume to be sweet to the taste. When the little pocket is partly filled with this drop of liquid the caterpillar turns it inside out in such a way that the liquid drop remains in position on top of the protruded pocket.
Perhaps you ask what is the good of all this complicatedarrangement? If you could see what happens when the little drop of what—for lack of a better name—we shall call honey-dew is exposed, you would begin to guess the reason. Wherever these larvae are found you will also find many ants wandering round among them, and the moment the honey-dew appears these ants begin to sip it up. When it is all gone the little caterpillar draws in its pocket again and presumably begins to store up another bit of liquid. It is certainly a curious example of what the naturalists call symbiosis, which simply means a living together of two animals, each helping the other in some way. In this case it is easy enough to see how the caterpillar helps the ant, but perhaps you are wondering in what possible way the ant may help the caterpillar. I hardly dare give the most plausible explanation for fear some one will cry out, "Nature-faker!" But fortunately the explanation is based upon at least one precise observation by W. H. Edwards, one of the most careful and reliable naturalists America has produced, who lived before the recent era of Nature-fakers and was never accused of sensationalism. Mr. Edwards saw an ant drive away from one of these caterpillars a little parasitic fly which apparently was searching for a victim. Consequently, it would appear that the ants helped the caterpillars by protecting them from these arch enemies.
This is by no means an isolated example of the relations between ants and other insects. It has been known for hundreds of years that the ants use the aphids as a sort of domestic milk-producer, attending the aphids at all times and even caring for their eggs throughout the winter season. As the plant-lice live in colonies, sucking the sap of their host plant, they are attended by great numbers ofants that feed upon the honey-dew which passes through their bodies. In many cases the ants have been observed to stroke the aphids with their antennae in a way which seems to induce the aphid to give out a drop of the sweet liquid for the ant to lap up. In a similar way these ants seem sometimes to stroke these little caterpillars with their antennae and thus to induce them to turn their little pockets inside out with the drop of liquid at the tip. This is certainly an unusual and most interesting relation between two insects far separated by their structural characters.
The little pocket that I have thus described is situated upon the seventh segment of the abdomen. Just back of it there are two other openings which are even more curious in their structure. These are provided with some slender tentacles on which there are circles of hairy spurs. These structures are a great puzzle to naturalists. It is difficult to explain what they are for unless we assume that they relate in some way to the honey-dew pocket on the seventh ring. The only plausible explanation is that these serve to advertise to the ants, by giving off a distinctive odor, that there is nectar near at hand to be had for the asking. They would thus beanalogousin a way to the fragrant scent of flowers which is for the purpose of advertising to the bee the fact that nectar or pollen or both are near at hand and may be had for the asking. In the case of these caterpillars, however, if this is the true explanation it is a most wonderful provision and one which would be likely to tax the ingenuity of man's mind for a long while before it was originated.
So this little butterfly which greets us in every spring, like "a violet afloat," to quote Mr. Scudder's happy phrase,is full of interest at all stages of its existence. It should lead one to a new respect for the familiar things in the natural world when one learns how baffling to the wits of the wisest scientist is this little creature with its protean forms and the wonderful structure of its caterpillars.
Scudder's BlueRusticus scudderi
This beautiful little butterfly is perhaps the most richly colored of all our northern Blues. The upper surface of the wings in the male is a nearly uniform hue, except for a narrow dark border around the margin. In the female there is, in addition, a series of black-centred orange spots inside of the black border, the series being more prominent on the hind wings than on the front ones. The under surface is very pale with distinct marks in black scattered over the basal two thirds, with a row of orange spots outside of these and another row of small blackish spots just inside of the blackish border stripe.
This butterfly is a northern species. It occurs in New England, New York, and Michigan, and thence extends far north into Canada. The caterpillar feeds upon blue lupine and apparently the butterfly is likely to be found in most places where this plant grows. The eggs are laid upon the leaves or stems and the little caterpillars come out of the shells through small holes which they have gnawed.
"The caterpillar," wrote Mr. Scudder, "has a very extensible head and flexible neck, and its manner of feedingimmediately after birth is rather remarkable; it pierces the lower cuticle of the leaf, making a hole just large enough to introduce its minute head, and then devours all the interior of the leaf as far as it can reach—many times the diameter of the hole—so that when the caterpillar goes elsewhere, the leaf looks as if marked with a circular blister, having a central nucleus; the nearly colorless membranes of the leaf being all that is left, and at the central entrance to the blister the upper membrane only." Later in its life it often modifies this feeding habit somewhat, and as it approaches full growth it is likely to devour the entire blade of the leaf.
These larvae have the curious nectar-secreting glands on the seventh abdominal segment which are discussed in connection with the preceding species. Many ants are attracted by this secretion so that it often happens that the easiest way to find the caterpillars is to look for these attendants. In New England there are two broods of the butterfly, one appearing early in June and the other late in July.