Pl.8.Small White Butterfly.Eggs, natural size and enlarged; caterpillar and chrysalids.
Pl.8.Small White Butterfly.Eggs, natural size and enlarged; caterpillar and chrysalids.
Pl.8.
Small White Butterfly.
Eggs, natural size and enlarged; caterpillar and chrysalids.
Larger ImagePl.9.Large White Butterfly (Summer Brood).1, 2male; 3, 4female.
Pl.9.Large White Butterfly (Summer Brood).1, 2male; 3, 4female.
Pl.9.
Large White Butterfly (Summer Brood).
1, 2male; 3, 4female.
The strongly-marked specimens (Plate14) are from Ireland, and are of the first or spring brood. The seasonal variation in this species is not so well defined in Ireland as in England.
A form of variation in the female, and most frequent perhaps in Irish specimens, is a tendency of the spots on the upper side of the fore wings to spread and run together, and so form an interrupted band.
Specimens with a distinct creamy tint on the wings are sometimes met with, but such varieties, as well as yellow ones (var.flava, Kane), are probably more often obtained in Ireland and Scotland than in England. Occasionally male specimens of the second brood have two black spots on the disc of the wing. Some forms of this butterfly have been named, and these will now be referred to.
Sabellicæ(Petiver), Stephens, has been considered as a species distinct fromP. napi, L. Stephens ("Brit. Entom. Haust.," I. Pl. iii., Figs. 3, 4) figured a male and a female assabellicæ, which he states differs fromnapiin having shorter and more rounded yellowish-white wings. No locality or date is given in the text (p.21) for the specimens figured; but referring to another example which he took at Highgate on June 4, he says that it agrees with his Fig.2.Probably, however, it was his second figure that he intended, the Fig.4of the plate, which is a female. This is rather more heavily marked with dusky scales than is usual in specimens of the first brood, at least in England, although it agrees in this respect with some Irish June examples.Fig.3represents a male which certainly seems to be referable to the spring form. Most authors givesabellicæ;as belonging to the summer flight, but this does not seem to be correct.
Var.napææis a large form of the summer brood, occurring commonly on the Continent, in which the veins on the under side of the hind wings are only faintly shaded with greenish-grey. Occasionally specimens are taken in this country in August, which both from their size and faint markings on the under side seem to be referable to this form.
Var.bryoniæis an Alpine form of the female, and in colour is dingy yellow or ochreous, with the veins broadly suffused with blackish grey, sometimes so broadly as to hide the greater part of the ground colour. This form does not occur in any part of the British Islands, but some specimens from Ireland and from the north of Scotland somewhat approach it.
All the early stages are shown on Plate10.
The egg is of a pale straw colour when first laid, but it soon turns to greenish, and as the caterpillar within matures, the shell of the egg becomes paler. The ribs seem to be fourteen in number.
The eggs are laid singly on hedge garlic (Sisymbrium alliaria) and other kinds of plants belonging to the Cruciferæ. The egg in the illustration was laid on a seed-pod of hedge garlic, but the caterpillar that hatched from it was reared on leaves of garden "nasturtium" and wallflower.
The caterpillar when full grown is green above, with black warts, from which arise whitish and blackish hairs. There is a darker line along the back, and a yellow line low down on the sides. Underneath the colour is whitish-grey. The spiracular line is dusky, but not conspicuous, and the spiracles are blackish surrounded with yellow. It has been stated that caterpillars fed upon hedge garlic and horseradish produce light butterflies, and that those reared on mignonette and watercress produce dark butterflies. Barrett mentions having reared abrood of the caterpillars upon a bunch of watercress placed in water and stood in a sunny window, but he does not refer to anything peculiar about the butterflies resulting therefrom. He states, however, that from eggs laid in June the earliest butterfly appeared within a month, and the remainder by the middle of August, only one remaining in the chrysalis until the following June.
Pl.10.Green-veined White Butterfly.Eggs, natural size and enlarged; caterpillar and chrysalis.
Pl.10.Green-veined White Butterfly.Eggs, natural size and enlarged; caterpillar and chrysalis.
Pl.10.
Green-veined White Butterfly.
Eggs, natural size and enlarged; caterpillar and chrysalis.
Larger ImagePl.11.Small White Butterfly.1, 2, 4male (spring), 3do. (summer); 5, 7, 8female (spring),6, 9,do. (summer).
Pl.11.Small White Butterfly.1, 2, 4male (spring), 3do. (summer); 5, 7, 8female (spring),6, 9,do. (summer).
Pl.11.
Small White Butterfly.
1, 2, 4male (spring), 3do. (summer); 5, 7, 8female (spring),
6, 9,do. (summer).
Caterpillars may be found in June and July and in August and September.
The chrysalis is green in colour, and the raised parts are yellowish and brown. This is the most frequent form, but it varies through yellowish to buff or greyish, and is sometimes without markings.
Generally distributed throughout the British Islands, but its range northwards does not seem to extend beyond Ross.
In Europe it is generally common, and extends through Western and Central Asia to Siberia, and, according to Leech, is found in North Japan. In Amurland and Corea it is represented by the formorientis, Oberth. It occurs in North-West Africa, the Canary Isles, and the Azores. In America it is found in the Northern States and in California.
The Bath White (Plate14) is such a rare visitor to this country, that any one who captures a specimen may congratulate himself on the event. During the whole of the last century not more than sixty specimens seem to have been recorded as taken in England, and ten of these were captured between 1895 and the present time. Nearly all of these were netted on the south or south-eastern coast, and in the months of July or August, but chiefly the latter. The occurrence of specimens in May or June appears to be quite exceptional.
Although it might be passed over for a Green-veined White,or other common butterfly, when seen on the wing, it is very different from any of our other species when seen at close quarters. In the greenish mottling of the under side of the hind wings, the male has some likeness to the female Orange-tip, but on the Bath White the green is heavier and less broken up. On the upper side of the fore wings the black markings comprise a spot, sometimes divided, at the end of the cell, and a patch on the tips of the wings; the latter enclose spots of the ground colour. The markings of the under side show through blackish on the upper side of the hind wings. The female differs from the male in having a black spot between veins 1 and 2 of the fore wings, and the markings of the hind wings are blacker, especially on the outer area.
The egg is stated by Buckler to be of a bright pinkish-red colour, agreeing in this respect, as well as in size, with the anthers of the flowers of mignonette, upon which plant it is laid in an upright position. The shape is compared to that of an acorn without the cup, and it has twelve or fourteen rather prominent ribs.
The full-grown caterpillar is bluish-grey, dotted with glossy black warts, from each of which there is a short blackish hair. The lines along the back and sides are yellow, or white spotted with yellow. Head yellowish, dotted with black, and hairy. August and September. It feeds on garden as well as wild mignonette (Reseda).
The chrysalis is at first similar in colour to the caterpillar, but it afterwards becomes whitish. It has numerous black dots, and is marked with yellow along the sides and on the back of the thorax.
The above descriptions are abridged from Buckler's more detailed account of the life-history of this species. Of the caterpillars resulting from thirty-three eggs, only two attained the chrysalis state, in September. One of these turned black and died in November, and from the other a butterfly emergedin the following June. The figures of caterpillar and chrysalis on Plate12are from Buckler's "Larvæ."
Pl.12.Bath White Butterfly.Caterpillar and chrysalis (after Buckler).
Pl.12.Bath White Butterfly.Caterpillar and chrysalis (after Buckler).
Pl.12.
Bath White Butterfly.
Caterpillar and chrysalis (after Buckler).
Larger ImagePl.13.Green-veined White Butterfly.1, 2male (spring), 5, 6,do. (summer); 3, 4female (spring), 7, 8do. (summer).
Pl.13.Green-veined White Butterfly.1, 2male (spring), 5, 6,do. (summer); 3, 4female (spring), 7, 8do. (summer).
Pl.13.
Green-veined White Butterfly.
1, 2male (spring), 5, 6,do. (summer); 3, 4female (spring), 7, 8do. (summer).
It has been suggested that specimens taken in July and August are the offspring of immigrants that arrive here in May, but there is no conclusive evidence of this. It has, however, been proved that our climate is not suitable for the permanent establishment of the species here.
The earliest writers on English insects called this butterfly "Vernon's Half Mourner," or "The Greenish Half Mourner." It was first mentioned by Petiver, some two hundred years ago, and about that time only two British specimens were known. One of these was taken in Cambridgeshire, and one at Hampstead. According to Lewin, who wrote about it in 1795, the name "Bath White" was given to the butterfly "from a piece of needlework executed at Bath by a young lady, from a specimen of this insect, said to have been taken near that place." In 1796 Donovan only knew of the Bath specimen; and in 1803 Haworth mentions a faded specimen taken in June at Gamlingay in Cambridgeshire.
The species is more or less common in many parts of Europe, but it seems to be most at home and abundant in the south. Its range extends to North Africa, Madeira, the Canary Isles, and the temperate parts of Asia, including Northern China and Corea.
This butterfly (Plate17), as its name suggests, has a large patch of orange colour on the outer third of its white, or creamy white, fore wings, and the extreme tip is blackish; at least, this is so in the male. The female is without the orange patch, and this is replaced by a smaller one of blackish-grey. The lower portion of this patch is broken up by the ground colour, and by white spots on the outer margin and around the tips of thewings. The hind wings, in both sexes, appear to be dappled with greyish-green, and this is caused by the green marking on the under surface of the wings showing through. Some specimens, chiefly from Ireland, have all the wings in the male, and the hind wings in the female, distinctly tinged with yellow. The discal black spot varies in size and in shape; often it is roundish, and sometimes it is crescent-like. It is always larger in the female than in the male, and may be entirely absent in the latter sex; but this probably occurs very rarely. Usually the orange patch of the male extends very near to the inner angle of the wing, but sometimes it is continued through to this point. It ranges in colour from deep to pale orange, and occasionally to almost yellow. Small specimens, some not more than one inch and a quarter in expanse, occur from time to time. In these dwarfs the orange patch does not reach beyond the black discal spot, which in normal specimens it usually does. This small form has been considered a distinct species, and the namehesperidishas been proposed for it. Female specimens with splashes or streaks of the male colour on the upper or the under sides have been noted not infrequently; and more rarely specimens with one side entirely male and the other entirely female have been taken.
The egg (Plate15), when freshly laid, is whitish, faintly tinged with greenish; it soon changes to yellow, and, later on, turns orange and then dark violet. When the latter colour appears, the little caterpillar may be expected to hatch out very shortly. The eggs are placed upright on the foot-stalks of the flowers, and may be readily found in June by searching the blossom-clusters of hedge-mustard or cuckoo-flower.
The caterpillar, when mature, is dull bluish-green, with raised dots and warts; from the former arise whitish hairs, and from the latter longer blackish hairs. There is a white line, or stripe, along the sides, and the underparts of the body are greener than the back. Both in colour and marking thecaterpillar agrees so closely with the seed-pods of its food-plant that its detection is not always easy. A peculiarity in very young caterpillars of this species, and also those of some of the "Whites," is, that the hairs are forked at the tips, and bear globules of moisture thereon (see figure and remarks on p. 3).
Larger ImagePl.14.Green-veined White (Irish).1male; 2, 3female.Bath White.4, 5male; 6female.
Pl.14.Green-veined White (Irish).1male; 2, 3female.Bath White.4, 5male; 6female.
Pl.14.
Green-veined White (Irish).
1male; 2, 3female.
Bath White.
4, 5male; 6female.
Pl.15.Orange-tip Butterfly.Egg, natural size and enlarged; caterpillar and chrysalis.
Pl.15.Orange-tip Butterfly.Egg, natural size and enlarged; caterpillar and chrysalis.
Pl.15.
Orange-tip Butterfly.
Egg, natural size and enlarged; caterpillar and chrysalis.
The caterpillars feed in June and July on lady's smock or cuckoo-flower (Cardamine pratensis), charlock (Brassica sinapistrum), hedge-mustard (Sisymbrium officinale), garlic mustard (S. alliaria), rock-cress (Arabis), horseradish (Cochlearia armoracia), dame's violet (Hesperis matronalis), watercress (Nasturtium officinale), etc.
The chrysalis, as will be seen from the figure (Plate15), is curiously elongated, and tapers towards each end; the outline of the back is curved, and the wing-cases bulge out into an angle about the middle of the under side. The colour is pale grey or whitey-brown, sometimes with a strong rosy tinge; the back is speckled with brownish, and has an olive-grey dorsal line, and the veins of the wings are well defined. This stage lasts, as a rule, from August of one year until May of the following year. When the chrysalis is first formed, it is green, with the wing-cases brighter, and this colour is sometimes retained. It has been stated that the chrysalids assume the colour of their immediate surroundings, and this may be so; but all that I have had under observation were of the colours described above, although some were fastened to green stem, others to muslin, and others, again, to glass.
Towards the end of May and in June is the usual time for this butterfly to be on the wing. It has, however, been noticed as early as about the middle of April, and as late as the middle of July, and rarely in August and September. The specimens, seen in the last-mentioned months, may have represented a second brood, and, if so, a very unusual event. Possibly, however, they may have been specimens whose emergence had forsome reason not understood, been retarded. There is at least one record of the insect remaining in the chrysalis for two winters.
Although generally distributed throughout England, Wales, and Ireland, and occurring in Scotland as far north as the Caledonian Canal, it seems to be more common in some districts than in others. Abroad, its range extends over Europe, and through Asia as far east as Amurland and China.
The graceful little butterfly figured on Plate19is creamy white, with a rather square black or blackish spot on the tip of the fore wings of the male. In the female the spot is reduced to some blackish scales on and between the veins. Occasionally there is a second brood in the year, and the specimens of this flight have smaller and rounder black spots in the males, and almost none at all in the females. Specimens of the female sex entirely devoid of black marking are referable to var.erysimi(see fourth figure in second row, Plate16). Series of each brood are shown on Plate16,which is reproduced from a photograph by Mr. Hamm. The lower specimen in each series has been reversed to show the seasonal variation of the under side. The row of specimens on the left are of the first brood, and the second and last examples in this series show the characters of var.lathyri—black tips to the fore wings, and dusky band-like shades on the hind wings; the under sides of the hind wings dull greenish—to which form a good many of our spring specimens belong. The specimens of the second generation are referable to var.diniensis. The species is sometimes referred toLeptosia, Hüb.
The egg, which is figured on Plate18, is yellowish-white in colour; it is ribbed, and rather glassy in appearance. The caterpillars have been known to hatch out about a week after the eggs were laid.
Larger ImagePl.16.Wood White Butterfly.
Pl.16.Wood White Butterfly.
Pl.16.
Wood White Butterfly.
Larger ImagePl.17.Orange-tip Butterfly.1, 5male; 2do. (Irish); 3, 6female; 4do. (Irish).
Pl.17.Orange-tip Butterfly.1, 5male; 2do. (Irish); 3, 6female; 4do. (Irish).
Pl.17.
Orange-tip Butterfly.
1, 5male; 2do. (Irish); 3, 6female; 4do. (Irish).
The caterpillar when full grown is, according to Hellins, "a beautiful green, the front segments minutely dotted with black; dorsal line darker green, edged with yellowish-green; spiracular line distinct, of a fine clear yellow, edged above with darker green; spiracles indistinguishable." The chrysalis in shape is something like that of the last species, but the back is not curved, and the ends are less tapered. The colour is a "lovely delicate green; the abdomen rather yellowish; just in the spiracular region there runs all round the body a stout pink rib, enclosing the greenish spiracles; from this a strong pink line branches off, bordering the outer edge of the wing-case, and the nervures of the wings themselves are delicately outlined in pink" (Hellins). Sometimes the chrysalids are green without marking.
Mr. A.M. Montgomery, who on one occasion had four batches of eggs, and the subsequent caterpillars, under observation, states that the caterpillars hatched about June 2 from eggs laid about May 22. Pupation took place about July 3, and, except from one batch that remained for the winter in the chrysalids, the butterflies emerged between July 16 and 22. The food-plant in this case was bird's-foot trefoil (Lotus corniculatus). The yellow pea (Lathyrus pratensis) is a favourite pabulum, but the caterpillar will also eat a vetch (Vicia cracca), and probably many other plants belonging to the order Leguminosæ. Caterpillars from the July butterflies would feed in August and September.
This fragile-looking little species is somewhat local, but is not altogether uncommon in some of its particular haunts. As its English name implies, the butterfly is fond of the woods, or, perhaps, is rather more partial to their shady rides and margins. On dull or wet days, it settles on the under side of a leaf. The first brood is on the wing in May, and the second—when this occurs, which is not every year—in July and August. In Ireland, where it is abundant in the south andwest, there seems to be only one flight, and this is in June. It may be well to remember that this butterfly does not like the pill-box, and will not settle down quietly therein.
Possibly the Wood White had a much more general distribution in England at one time than it now seems to have. It was not uncommon in parts of Sussex some years ago, but there appears to be no record of its occurrence there now. It is certainly much scarcer in the New Forest than it used to be. However, it is still to be found, no doubt, in many parts of England and Wales, but chiefly perhaps in the counties of Berkshire, Devonshire, Cornwall, Worcestershire, Herefordshire, Lancashire, and Cumberland. Also in the south and west of Ireland. It occurs throughout Europe, Western and Central Asia, and its range extends eastwards through Siberia, Amurland, China, and Corea to Japan.
This usually scarce butterfly (Plate21) is of a primrose-yellow colour in the male, and, as a rule, almost white in the female; sometimes the latter sex is of the yellow male colour. The outer margin of the fore wings is broadly black in both sexes, but there are some more or less united spots of the ground colour in the black towards the tips of the wings, and below vein 3 the black is usually confined to the outer margin. There is a black spot near the middle of the wing, and some blackish dusting quite near the base of the wing. The hind wings have a pale orange central spot, sometimes two spots, and the blackish border on the outer margin is generally narrow, and often interrupted or broken up into spots. The fringes of all the wings are pinkish, as also are the antennæ. The egg is pearly yellowish-white when first laid; a few days later the top becomes transparent, white, and glassy, shading downwards into yellow, and then clear rosy orange; the base ispale, but less transparent than the top. It has a number of transverse ribs, ranging from nineteen to twenty-two. Before the caterpillar hatches out, the egg changes to a purplish leaden colour.
Pl.18.Wood White Butterfly.Eggs, natural size and enlarged; caterpillar (after Buckler) and chrysalis.
Pl.18.Wood White Butterfly.Eggs, natural size and enlarged; caterpillar (after Buckler) and chrysalis.
Pl.18.
Wood White Butterfly.
Eggs, natural size and enlarged; caterpillar (after Buckler) and chrysalis.
Larger ImagePl.19.Wood White Butterfly.1, 4, 6male; 3do. (var.); 2, 5, 7female.
Pl.19.Wood White Butterfly.1, 4, 6male; 3do. (var.); 2, 5, 7female.
Pl.19.
Wood White Butterfly.
1, 4, 6male; 3do. (var.); 2, 5, 7female.
The caterpillar in October, before hibernation, is about a quarter of an inch long, and deep clover-green in colour; it has a number of pale, shining warts along the back, from each of which there is a moderately long black bristle, and there is a pale yellowish-white stripe above the black spiracles. The head is pale ochreous green, with warts and bristles as on the body. It rests upon a pad of silk spun on the centre of a leaflet. When full grown the colour is clear light green, but has a darkish velvety appearance, due to the entire surface being densely sprinkled with black warts, the bristles from the warts on the back are black, and those on the lower surface are white, the line above the spiracles, which are white outlined with black, is made up of lemon-yellow, orange-vermilion, and orange with an upper border of white. The head, claspers, and legs are green. It feeds in June, and again in August, on clover, trefoil, etc. The figure on Plate20is after Hübner.
The chrysalis is very similar to that of the Clouded Yellow, the chief differences are that the head-beak of the present species is straight instead of being slightly upturned, and the tip of the wing-case extends further down the body.
The above particulars of the early stages of the Pale Clouded Yellow are adapted from Mr. Frohawk's account of the life-history of the species (Entomologist, 1892 and 1893).
From eggs laid in September by a captured female, Mr. Williams reared two butterflies in November of the same year. Other caterpillars from the same batch of eggs hibernated and recommenced feeding in the spring, but failed to attain the chrysalis state. Young caterpillars from eggs obtained in August were successfully hibernated by Mr. Carpenter, and many of these produced butterflies in the following May.
In rearing this species from eggs laid in the autumn, a fairly dry treatment appears to be the best. Protect the young caterpillars from frost, and do not water the plants during the winter. When they become active again, about February, transfer them to other growing plants, which should be kept ready for the change. Do not water the plants much, or wet the foliage at all, and keep a sharp look-out for earwigs.
It seems pretty clear that this species passes the winter as a caterpillar, and from the evidence available it appears equally certain that the caterpillars would not survive an ordinary winter in this country. Possibly, however, in very mild winters, or in certain warm nooks on the south coast, some may be able to exist until the spring, and then complete their growth and reach the butterfly state. In such native-born butterflies the ancestral migratory habit may be lost, owing to climate, and they would not, therefore, wander far from the spot where they emerged from the chrysalis, but found a colony, which probably would be cleared off sooner or later by the severity of an English winter.
The Pale Clouded Yellow was not mentioned as an English butterfly until Lewin wrote about it in 1795. He states that he only met with it "in the Isle of Sheppey and on a hilly pasture-field near Ospringe in Kent." He seems to have noted it in different years at both places. Stephens, in 1827, referred to it as a rare British species, and from that date until 1867 it seems to have been common only in 1835, 1842, 1857, and 1858. In 1868 it was abundant in the southern and eastern counties, and was observed as far north as Lancashire and Yorkshire, also in Ireland. It was common on the south coast in 1872, and rather more so in 1875, when it spread into Essex and Suffolk, and also inland. Until 1875 the butterflies seem only to have been noticed in the autumnal months, but in that year specimens had been seen in May and June. In 1876 the species was pretty plentiful, but after that date it did not againoccur in numbers until 1892, when it was recorded from most of the southern and eastern counties. In 1893 one or two specimens were reported as seen in April or May, but less than a dozen were recorded as captured during the autumn of that year. Not much was seen of the butterfly again until 1899, when a score or so were recorded from Kent. Two or three specimens were seen on the south coast in June, 1900, and the species was plentiful in the autumn of that year in many parts of the country. Single specimens were seen in June, 1901, and in the autumn the butterfly was again fairly common in several southern counties, and abundant in parts of Essex. In 1902 a male was taken near Dartford in March, and one example in May in a locality where two specimens had been captured on October 20 of the previous year; six males and one female were obtained between June 27 and July 12 at Sheerness. The summer of 1902 was a cold one, and, with the exception of four specimens at Folkestone in August, the species was not again seen during that year or the following one; but in 1904 a good many specimens were secured at Chatham in September, and one or two at Margate in August.
Pl.20.Pale Clouded Yellow Caterpillar.(After Hübner.)
Pl.20.Pale Clouded Yellow Caterpillar.(After Hübner.)
Pl.20.
Pale Clouded Yellow Caterpillar.
(After Hübner.)
Larger ImagePl.21.Pale Clouded Yellow.1, 2male; 3, 4female.
Pl.21.Pale Clouded Yellow.1, 2male; 3, 4female.
Pl.21.
Pale Clouded Yellow.
1, 2male; 3, 4female.
When it occurs in this country the butterfly should be looked for in clover and lucerne fields.
Common throughout the Palæarctic Region. It is probably a species of Eastern origin, but with a tendency to spread westward.
In its typical colouring—orange with broad black borders—this butterfly (Plate22) will be recognized the first time it is seen. Both sexes have a black spot about the centre of the fore wings, and a deep orange spot near the middle of the hind wings—the latter is subject to variation in size and shape. Thefemale usually has the black borders spotted with yellow, but in some examples these spots are almost (Plate24,Fig.1) or quite absent. Another form of the female, known as var.helice(Plate24,Fig.2), has the orange colour replaced by yellowish-white, and in some years is not altogether uncommon. Between this yellowish-white at one end of the colour range and the typical orange at the other, specimens showing all the intermediate shades have been obtained, chiefly by rearing the butterflies from eggs laid by a femalehelice. One of these intergrades will be seen on Plate24,Fig.3. The males vary, especially bred ones, from "deep rich orange to the palest chrome yellow; the marginal bands also vary in width; in many examples the yellow nervules run through the borders of all the wings. A large proportion of the males have the hind wings shot with a beautiful amethystine blue" (Frohawk).
The egg (Plate23) is oval, tapering towards each end, very pale yellowish in colour at first, but afterwards becoming darker yellow, and then pink. The eggs are laid, as shown in the figure, on the upper side of a leaf of clover or lucerne, sometimes singly, but often in small batches.
The caterpillar when full grown is deep green with minute black dots, from which fine hairs arise, and a pink-marked yellow, or whitish, spiracular line. The head is also green, rather downy, and small in size. When first hatched the caterpillar is brownish, but soon changes to greenish. It feeds on clover (Trifolium), trefoil (Lotus), melilot (Melilotus), etc., in June and again in September or October.
The chrysalis is yellowish-green above, somewhat paler below; the wing-cases are rather deeper in tint than the thorax and back, and have a central black speck and a row of slender marks at the edges. The body is marked with a splash of reddish and tiny black dots on the under side. The beak-like projection from the head is dark green above and yellow beneath.
The figures of the caterpillar and the chrysalis are taken from Buckler's "Larvæ of British Butterflies," and the descriptions of these stages by the same author have been followed.
The Clouded Yellow has a great fancy for clover or lucerne fields, and should be looked for in such places in August and September. It is not very difficult to rear from the egg, so that if a female is captured in August (the spring ones should not be taken), it would be a good plan to try to induce her to lay some eggs. The best method to succeed in this is to pot up a growing plant of clover, and over this place a glass cylinder with a muslin cover. (See further directions in the Introduction, page 28.)
This butterfly, which was known, to the earliest English authors as the "Saffron" or "Spotted Saffron," has always, no doubt, been erratic and uncertain in its appearance in this country, sometimes becoming increasingly abundant for three, four, or even five years in succession, and then scarce or entirely absent for similar periods. The most recent years of plenty, or when it was fairly common, were 1877, "the great Edusa year," 1892, 1893, 1894, 1895, 1899, 1900, and 1902. In some of these years the Pale Clouded Yellow was also common.
In some of the warmer countries that this butterfly inhabits it has certainly three, and possibly four, broods in the year. It is therefore conceivable that at times its increase in numbers may become very great in some particular area. At such times swarms of the surplus butterfly population set out to seek fresh fields and pastures new. Some portion of these flights reach our country from time to time, and this probably always occurs in the spring of the year. The weather conditions being favourable, the offspring of the visitors put in a welcome appearance in the autumn, and not only gladden the heart of the entomologist, but add a charm to the countryside which every one can appreciate.
The butterfly has probably occurred, at some time or other,in almost every county in England and Wales, Ireland and Scotland, extending even to the Orkney Islands (1877).
Its home appears to be in North Africa and South Europe, whence it spreads over the greater part of Europe and Western Asia.
Note.—According to Kirby, this butterfly should be calledEurymus hyale, Linn., and the Pale Clouded Yellow be known asEurymus kirbyi, Lewis.
This butterfly (Plate26) has the tips of the fore wings sharply pointed, and there is a rather acute angle about the middle of the outer margin of the hind wings. The colour of the male is bright sulphur yellow, with a central orange spot on each wing, that on the hind wings usually the largest; there is also a rusty dot at the outer end of the upper veins and along the front margin of the fore wings towards the tip. The female is greenish yellow, and is marked similarly to the male. In both sexes the horns (antennæ) are reddish, and the long silky hair on the thorax is a noticeable character. It is probably this insect to which the name "butter-coloured fly," contracted into butterfly, was first given; anyway, it is the only species to which the name applies so well.
The egg. If the under sides of the leaves of buckthorn (Rhamnus catharticus) or of the berry-bearing alder (R. frangula) are examined in May or June, the eggs of this butterfly may be found thereon. They are often placed on a rib of the leaf, but sometimes they are laid as shown in the illustration (Plate25). At first the colour is pale greenish and rather glossy, but it soon changes to yellowish, and later on, when the caterpillar has formed inside, to a dull purplish-grey.
The caterpillar when full grown is green, merging into bluish-green on the sides, thickly powdered with shining blackspecks. There is a pale line on each side below the spiracles. It feeds in June and July on both kinds of buckthorn, and will generally be found resting along the main rib of a leaf.
Larger ImagePl.22.Clouded Yellow.1, 3male; 2, 4female.
Pl.22.Clouded Yellow.1, 3male; 2, 4female.
Pl.22.
Clouded Yellow.
1, 3male; 2, 4female.
Pl.23.Clouded Yellow.Eggs, natural size and enlarged; caterpillar and chrysalis.
Pl.23.Clouded Yellow.Eggs, natural size and enlarged; caterpillar and chrysalis.
Pl.23.
Clouded Yellow.
Eggs, natural size and enlarged; caterpillar and chrysalis.
The chrysalis is bluish-green in colour and of a curious shape. The sharp yellowish and brown beak-like projection in front and raised brownish bases of the wing-covers, together with the humped thorax, somewhat resemble a bird's head when seen from the front. Then, again, the enlarged wing-cases, which are rather greener than the other parts, in conjunction with the general outline, give a very good imitation of a curled leaf.
The butterfly is very constant as regards colour and marking, but occasionally the fore wings may be more or less suffused with orange, and in this respect assumes the coloration of the South European species known asG. cleopatra. The attempt has been made to establish the last-named butterfly in Ireland, but the experiment seems to have been only partially successful. Sometimes female specimens are found to have splashes of the male colour on their wings. Occasionally their colour is intermediate between their own proper tint and that of the male, and more rarely the wings on one side may be yellow, as in the male, while those on the other side are greenish, as in the female. Such specimens are termed gynandrous examples, and sometimes hermaphrodites. The latter, however, is not correct.
An unusual variation of the butterfly is shown on Plate27.This has large oval pale brownish-orange marks on the under side of the wings. It was taken in the New Forest.
The Brimstone butterfly enjoys a longer existence in the perfect state than any of the other British species, with the exception, perhaps, of the Tortoiseshells and their allies. It leaves the chrysalis at the end of July or beginning of August, and is usually quite common during the latter month. After this it takes up its winter quarters, from which, however, it may be tempted to come out whenever the day is sufficientlywarm and sunny for it to indulge in a few hours' flight. The fine condition of some of the specimens that are seen in May or June has suggested the possibility of such specimens having remained in the chrysalis during the winter, but it is not at all probable that they do so. It may be seen any sunny day from March, or even February, to June in almost every English and Welsh county where its food-plant grows, and locally in Ireland. The best time to take specimens is in the autumn, when they are often to be seen in numbers flying along the rides in or on the outskirts of woods, and also in clover fields.
Distributed over the whole of temperate Europe, and extending through Asia to the far east and to North Africa.
The thirty butterflies now to be considered belong to the Nymphalidæ, which has a larger membership than any other family of butterflies. It is divided into several sub-families, but only four of these concern us; these are Apaturinæ (1 species), Nymphalinæ (17 species), Danainæ (1 species), and Satyrinæ (11 species). The next butterfly is our only representative of Apaturinæ.
On account of its large size and the beautiful purple sheen over its brownish-black velvety wings, this butterfly (Plate29) is always counted a prize by the collector. It is, however, only the male that dons the purple, and he only when seen from the proper angle. The female is without the purple reflection and her wings are browner, but the white spots on the fore wings and the white bands on the hind wings are rather wider than those of the male. Above the anal angle of the hind wings, in both sexes, there is a black spot, ringed with tawny and sometimes centred with white, and a tawny mark on veins 1 and 2. As will be seen on turning to the figures onPlate31,the under side of this butterfly is exceedingly pretty. On the same plate there is a figure of the rare variety known asiole(for the loan of which I am indebted to Mr. Sabine), in which most of the white spots are absent or obscured. Intermediates between this extreme form and the type also occur, but all such aberrations are uncommon.