Fig. 22.Fig. 22.Web of Lackey Caterpillars.(Photo by W. J. Lucas.)
Fig. 22.Web of Lackey Caterpillars.(Photo by W. J. Lucas.)
The full-grown caterpillar is slaty blue above; along the middle of the back is a bluish white line, bordered on each side by a reddish-orange-lined black stripe; towards the lower limit of the slaty blue colour is a black edged reddish-orange line, and below this again the ground colour is flecked with orange, sometimes forming a line in the region of the spiracles; there are two velvety black spots on the back of the ring nearest the head, and a smaller black spot on each side of the next two rings; the hairs are brownish, rather more numerous on the sides than on the back. Head slaty-blue with two black eye-like spots. It feeds from April to June on hawthorn, sloe, and various fruit trees in orchards and gardens; also on birch, elm, oak, sallow, willow, etc.
Chrysalis blackish, rather downy enclosed in a doubleoval-shaped cocoon; the inner compartment is of rather closer woven silk, and is thickly covered with a yellowish substance, which is ejected by the caterpillar as a fluid, and afterwards drying forms a sulphur-like powder on the cocoon, and in a lesser degree on the chrysalis also. The moth is on the wing in July and August, but it is rarely seen in the daytime, and not often at night, except when attracted by light into the house, or to the gas or electric lamps. It is exceedingly easy to rear, either from eggs or from collected caterpillars; the latter are often abundant.
Generally distributed throughout England, but becoming scarcer from the Midlands to Lancashire and Yorkshire, and not often occurring further north than the last named county. In Ireland it is unknown in the north, but occurs in many parts of the south and south-west.
This also is a variable species. Most frequently the fore wings of the male are pale buff, cross lined, and more or less clouded with brown; hind wings brown. The female has all the wings reddish brown, the front pair being crossed by two pale buff lines. The fringes are pale buff, chequered with brown in both sexes. Colour and marking are, however, subject to considerable variation. Sometimes all the wings are pale buff (male), or reddish brown (both sexes), and the fore wings without marking. The cross lines on fore wings of the female may be either very slender or very broad; occasionally almost the whole of the basal area up to, and including, the first cross line is buff. Two examples of each sex are shown on Plate48.
The eggs are laid in a similar manner to those of the last species, around stems of wild carrot, sea wormwood, and otherplants that flourish in the insects' favourite haunts, which, in this country, are the salt marshes along the estuaries of the Thames and Medway.
The caterpillar is black, inclining to bluish between the rings; along the back are four much broken reddish orange lines and a central bluish line; a bluish stripe followed by a reddish one along the sides, and below this the colour is bluish, speckled with black; the hairs are golden brown. Head blackish grey, without black spots (Plate49, Fig. 3).
The chrysalis and its cocoon are similar to those of the Lackey, and spun up among herbage.
The moth emerges in July and August and, although it may be occasionally attracted by light, is rarely seen in the open. The caterpillars are to be found, most years, in plenty from May to July. They feed on almost every kind of plant growing on the salterns, and as they are fond of sunning themselves on sea wormwood, sea plantain, etc., are easily seen at such times. In dull weather they retire to their webs, which are generally rather low down in the herbage. In confinement they will do very well if supplied with fresh sprays or leaves of almost any fruit tree, or of birch, whitethorn, etc. The receptacle containing them should be constructed and placed so that the caterpillars get plenty of air and sunshine. It is considered desirable to sprinkle both food and caterpillars with water now and then; some rearers deem it necessary to put a tiny pinch of salt in the water used for sprinkling; and in my own experience I have found that better results were obtained when the food was thus treated than when the salt was omitted.
On the continent this species occurs in woods, and on heaths, etc., but in Britain it is seemingly confined to salt marshes. Although it has been recorded from the Suffolk coast, and other places, the best localities for it are probably the salterns, from Gravesend to the Isle of Sheppey, and at Southend and Shoeburyness.
Plate 48
Plate 49
Malacosomahybr.schaufussi, Standf.—In 1884 Dr. Standfuss made some experiments in crossing three species ofMalacosoma, and one of these was the pairing ofM. neustria♂ withM. castrensis♀; the offspring he christened as above. Since that time others have succeeded in crossing the two species with varying results.
On August 13, 1906, Mr. Percy Richards sent me a small batch of eggs (Plate49, Fig. 2a) laid by a female,M. castrensis, that emerged in a breeding cage, and had paired with a captured male,M. neustria, he introduced. The larvæ hatched out one or two at a time, from April 7 over a period of more than a fortnight. Few of the caterpillars would commence to feed, and of those that took to the plum and sallow with which they were supplied, only four reached maturity. Three of these pupated during late June and early July, and three moths, all females, have emerged up to date, one on July 28, another on August 6, and a third on August 13. The second specimen was very much crippled, probably owing to the cocoon having been accidentally injured. One caterpillar was still feeding on August 14, but died about the 26th.
The mature larva (Plate49, Fig. 2) has the head and markings thereon likeneustria, also the black spots on the first thoracic segment, but they are rather large and inclined to unite. The bluish line along the sides is dotted and freckled with black rather more thickly than incastrensis; the dorsal line is very thin, but bluish as incastrensis, and the red lines on each side of it are broad.
In colour the three moths are deeper brown than any form of either parent species that I have seen, but the transverse lines, and especially the outer, are most like those ofneustria.
It should be mentioned that much information on Hybridism in the Lackey moths and other species will be found in Tutt's "British Lepidoptera," vol. ii.
In its typical form the male of this species (Plate50, Figs. 1, 2) is ashy grey, with a darker central band on the fore wings; and the female is dusky greyish-brown, also with a darker band. The colour of the male varies in shade from almost whitish (var.pallida, Tutt), to blackish grey; in the paler forms the central band of the fore wings is often of a purplish tint, and in the darkest forms the band is almost black. The female var.pallida, is pale buff.
The eggs, which are brownish, inclining to reddish on the micropylar area, are covered with dark grey hairs from the body of the female and laid side by side in a chain-like arrangement on a twig of hawthorn or sloe (those figured on Plate51were deposited in a box, and not securely attached). From eight to twelve is said to be the usual number in a batch, and each female will deposit an average of 160 eggs.
The caterpillars do not hatch out all at the same time, but by ones and twos, at intervals spreading over a period of two, or perhaps three, weeks. Several forms of the caterpillar have been described, but the ground colour is generally more or less black above and greyish on the sides; the ornamentation comprises interrupted white or whitish stripes, streaked or clouded with reddish, and reddish warts; the hairs are reddish brown. The example figured on Plate51was from eggs laid by a female moth in Selkirk, South Scotland. From the age of three weeks until it became full grown it was black marked with yellow on the back and orange on the sides; hairs pale greyish mixed with black ones, especially on the back towards the black, glossy, and somewhat hairy head. It hatched on April 26, was reared on plum, pupated early in June, and the moth, a darkish grey female, emerged on July 31. Another caterpillar that hatched on May 1, and two others from still later hatchings, were then in chrysalis.
Plate 50
Plate 51
The caterpillar may be found from April to June on hawthorn and sloe, and it is said also on birch, oak, sallow, apple, bramble, etc. Those that I have found resting by day on shoots of hawthorn, apparently enjoying the sunshine, have almost invariably been "ichneumoned"; but others that came up after sunset to feed on the shoots were generally healthy. Usually the caterpillar feeds up and pupates the same year, but on the moors in Aberdeenshire and some other parts of Scotland it is said to hibernate and to complete its life cycle the following summer and autumn. Furthermore, the moths from these winter larvæ are much darker than normal, and have been doubtfully referred to var.ariæ, Hübn., a form found in the Alps, Scandinavia, and Finland.
The moth is out in August and September, and occurs in wooded districts throughout the southern half of England, but northwards from the Midlands it is uncommon; it is found in several parts of Scotland to Inverness. In Ireland it is reported (Birchall) to have occurred in Killarney, and Kane mentions that "a blackish form was taken at Magilligan, near Derry, by W. Salvage. Its larvæ were feeding on blackthorn." The range abroad extends through Europe to Armenia and Asia Minor.
This is a rather thinly scaled moth; the general coloration is sooty brown; the wings are suffused more or less with greyish; there are two pale ochreous cross lines on the fore wings, the first enclosing a reddish brown basal patch; hind wings rather paler with a diffuse whitish central band; fringes brown chequered with pale ochreous. Head brown, collar brownish, tipped with pale ochreous in the male. The female is rather larger than the male. The moth is figured on Plate50, and the eggs and caterpillar on Plate53.
The eggs, which are laid on the bark of trees, are whitish grey, variegated or mottled with darker grey.
The caterpillar hatches out in April, and when nearly full grown is ochreous, but so thickly dotted and freckled with black as to appear of a dark brown coloration; the back is clothed with dark short hairs, and the sides with long paler hairs; on the back of the first ring is a reddish brown mark divided by a white line; a double row of whitish dots along the back, most distinct on rings two and three, where they are placed on a velvety black bar; on each side of the white dots is a reddish brown interrupted line. Head ochreous brown, thickly dotted with black and clothed with pale hairs. Underparts ochreous, spotted and lined with blackish. Feeds on the foliage of most trees, and is said to eat lettuce. April to June.
Chrysalis glossy red brown, in a cocoon spun up among dead leaves, etc., under loose bark, or on the ground.
The moth does not emerge until October, and in that month, but more frequently in November and December, the males may be seen around gas lamps quite late at night.
Although found chiefly in woods it is not essentially a woodland species, as it occurs in districts where there are no woods but plenty of trees growing in parks, fields, or even hedgerows. It is fairly common generally throughout England and Wales, but becoming rather more local northwards to Cumberland. It occurs through Scotland to Sutherland, but is nowhere common. In Ireland it is widely distributed, and not uncommon near Dublin, and at Favour Royal, Tyrone. Abroad it ranges through Northern and Central Europe.
Also a brownish insect with somewhat thinly-scaled wings. The fore wings are light reddish brown with a whitish patch at the base, a white spot about the centre, and a whitish transverse line beyond; the hind wings are smoky brown and have a pale central band. The female, which is larger than the male, has a conspicuous greyish anal tuft, the hairs from which she uses to cover over her pale oily green eggs when they are deposited in clusters on twigs of hawthorn or sloe in February or March. Plate50, Figs. 5, 6; Plate53, Figs. 2, 2a.
Plate 52
Plate 53
The caterpillar is black or greyish black, with reddish brown hairs, and a series of black-edged yellowish brown, or reddish brown blotches on each side of the back; these blotches are outlined in pale yellowish and occasionally connected by a line of the same colour. From the time they are hatched until nearly mature the caterpillars live in companies on a closely woven web of silk on a branch of hawthorn or sloe, only leaving their habitation to feed. These webs may often be seen on hedgerows from May to July. The brown chrysalis is enclosed in a solid-looking oval cocoon of a pale ochreous or whitish colour. Not all the moths emerge the following year: some will remain in the chrysalis over two or three winters, and occasionally they have been known to emerge seven years after pupation. The moth is said to be fully formed within the chrysalis all the time, but for some reason will not emerge, although if extracted from its shell, the moth has been known to expand its wings in the ordinary way. Barrett states that in the middle of February, after a moth had emerged, he "put a large number of cocoons upon a warm mantelpiece and obtained scores of moths within a few hours."
Generally distributed over the southern half of England; plentiful in some years in the Southern and Eastern Counties. Northwards and in Scotland it is local and less frequent. Kane states that in Ireland it is very locally abundant. The range abroad is through Central and Northern Europe to Southern Lapland, and eastward to Siberia and Amurland.
The three moths, one male and two females, shown on Plate52, were reared from caterpillars obtained in Kent, and theyrepresent the more or less ordinary South English forms of the species. Sometimes the ground colour of the male is more distinctly reddish, or rust tinted, and the yellowish bands narrower on all the wings. Or the bands may be much broader than in the male figured, and the widening is effected by extension in the form of rays towards the outer margins of the wings. A form that has been referred to, in error, as var.roboris, Shrank (=marginata, Tutt), has the outer margins of all the wings broadly yellow. I have not seen an English example of this form, but I have a reddish specimen in which the yellow band on the fore wings is broader than usual, and the whole of the outer third of the hind wings yellow, with a slight brownish shade on the external margin; this issemimarginata, Tutt, and is also identical with var.roborisof other British authors. The white spot usually present on the fore wings varies somewhat in size and shape; it is often seen on the under as well as the upper surface of the wings, except in the lighter coloured forms.
Var.callunæ(The Northern Eggar), is shown on Plate54. The chief features of this form are the generally darker coloration in both sexes, the yellow patch at the base of the fore wings of the male, and the outward turn of the lower ends of the yellow bands. All these characters are subject to modification; the yellow bands may be very narrow at one extreme, or greatly widened at the other, and the hind wings may occasionally be bandless; the basal patch is often of large size, but in some examples it is entirely absent. Sometimes the bands are greenish in colour (var.olivaceo-fasciata, Cockerell), and more rarely, perhaps, the greenish tinge extends over the whole of the wings (ab.olivacea, Tutt). It should be noted here that the var.olivaceo-fasciatahas occurred once or twice in South England, but this phase of aberration seems to be more connected withcallunæthan withquercus.
Plate 54
Plate 55
Callunæwas not recognized as British until the year 1847, when it was introduced as a species distinct fromquercus. The late Richard Weaver, who gave it the English name of the "Scotch Eggar," took specimens of the moth at Rannoch in 1845, and he found caterpillars in that year, as well as in 1844 and 1846. It is now well known to occur not only in Scotland, including the Hebrides and Orkneys, but also on the moors of Northern England, and in Ireland and Wales. In North Devonshire it is found not uncommonly in the Exmoor district, and it has been recorded from various parts of the New Forest in Hants.
The egg ofcallunæis figured on Plate55. It appears rather polished, and in colour is pale brown mottled with darker brown. The eggs are stated to be deposited whilst the female is on the wing, and consequently they fall to the ground or are arrested in their descent by the herbage over which they are scattered.
The full-grown caterpillar ofquercus, beneath the brownish fur with which the body is clothed, is dark brown on the back and rather violet brown on the sides; the ring divisions are velvety black; there is a white stripe along each side and below the stripe some reddish marks; the ring nearest the head is edged with reddish, and the next two rings each have two reddish centred white spots. The dull purplish brown chrysalis is enclosed in a hard oval-shaped cocoon which is spun up on or near the ground in a flimsy web among herbage, dead leaves, etc. Sometimes it is placed among the twigs of the food plant.
In Southern England the caterpillars hatch from the egg in August and usually hibernate when quite small. They feed up during the following spring and early summer, perhaps in June or July, and the moth appears in July or August. Occasionally, however, a few individuals depart from the general habit and complete their growth the same year, hibernate in the pupal stage, and produce moths the next year, possibly earlier than hibernating caterpillars. On the other hand, perhaps owing to adverse weather conditions, feeding after hibernation may be continued well on into the autumn, when the caterpillars pupate,but emergence of the moth is postponed until the following year, the second after hatching from the egg.
In the case ofcallunæ, at least as regards its normal habit in Scotland and southwards to the moorland districts of Yorkshire and Lancashire, the young caterpillar hibernates the first winter, feeds through the following summer, and passes the second winter as a chrysalis, the moth emerging in the following May or June.
Generally speaking, then, it may be stated thatquercushas a twelve-month life cycle, whilst that ofcallunæextends almost or quite to twenty-four months, of which at least twelve months are passed as a caterpillar. However, as has been noted,quercussometimes passes one winter as a caterpillar, and another as a chrysalis, thus assuming thecallunæhabit; whilstcallunæoccasionally attains the perfect state during the summer following that in which the caterpillar left the egg.
The food plants comprise bramble, dogwood, hawthorn, heather (Calluna), and various low plants; it is even content with ivy.
Newman, in theEntomologistfor 1845, gives a life history of the Northern Eggar (callunæ), and from this the following details are extracted. The male flies rapidly over the heather by day at the latter end of May or beginning of June; its flight is jerking or zigzag, and its object is evidently to find the female, who rarely moves until impregnation has taken place. Subsequently the female flies over the heather, dropping her eggs at random as she flies, and the eggs, having no glutinous covering, do not adhere to any object which they may accidentally touch in falling. On emergence from the egg the young caterpillar is dark ash-coloured, the divisions between the rings of the body being indicated by two minute orange streaks, each of which is accompanied by a small black spot. After the first moult the ground colour becomes more smoky, the divisions velvety black, and on each ring a triangular orange spot appears; these markings become more conspicuous later on, and by the end of October, when it hibernates, they are very distinct. It rests in a straight position, and, if disturbed, falls off its food plant, and rolls in a ring with its head slightly on one side.
Plate 56
Plate 57
The habits of the Oak Eggar moths (quercus) are pretty much the same as those of the Northern form, except that the moths fly in July and August, and frequent hedgerows, the borders of woods, heathy commons, and cliffs and sand dunes at the seaside.
A bred female of either form will attract numerous males, and even the receptacle in which a newly emerged female has been placed is almost as effective as the lady herself. When staying at a cottage on the edge of a moor near Lynton, North Devon, some years ago, I had some pupæ of the Oak Eggar. One day, late in July, quite a number of males entered the cottage and made their way to the cage in which the pupæ were, and I had no difficulty in boxing several of them. The next day I put the female moth, which had emerged the previous day, into a roomy chip box, and carried it in a satchel to the moor, where it was placed on the ground, the males began to arrive soon afterwards and some fine examples were secured. Although the female was taken on the moor only on the one occasion, that satchel continued to be an object of interest to the male Eggars for several days afterwards.
Generally distributed, and often common in some localities, throughout the British Isles. Abroad, its range extends over Europe into Asia Minor, Armenia, and Siberia.
This moth is usually brown in colour. The fore wings are inclined to dark reddish brown, and have a pale ochreous brown curved band or ring at the base, a slightly curved line or band of the same colour beyond the middle of the wing; central spotwhite, finely margined in black. Except that the female is generally larger, and the cross lines usually less distinct, the sexes are much alike. This brown form occurs most frequently in Britain, but in parts of the Kentish and Sussex coast, and especially the Romney Marsh district, a yellowish form is obtained. In such specimens the cross lines are darker. In both forms one or both cross markings may be faint or quite absent, and even the white central dot, which varies in size and shape, may be missing. Sometimes the outer band is distinctly broad and outwardly diffuse (Plate56).
The eggs, which appear to be laid loosely, are pale whitish brown, roughened with darker brown, and the micropylar area is purplish brown. Some that I received on March 2, 1907, appeared to be on the point of hatching on the 5th of that month, but no larva came out, although one of the eggs was chipped at one end. It has been frequently stated that the caterpillars hatch out in the autumn and hibernate, but as has been pointed out by Tutt ("Nat. Hist. Brit. Lep.," ii. 20), the eggs of this species probably do not hatch until some time during February or March, although when kept indoors the caterpillar has emerged from the egg in January.
The full-grown caterpillar is black, velvety between the rings, covered with golden brown hair on the back and greyer hair on the sides, among which are some black ones; three interrupted whitish lines on the back; some of the hairs along the middle of the back stand erect and form a ridge, looked at from either end. Head lightish brown in colour, lined with black. Feeds in the spring months and up to June chiefly on various kinds of grass. Among many of the plants that it has been known to eat are trefoils, bird's-foot (Ornithopus), sea thrift (Statice), heather, sallow, hawthorn, sloe, plum, bramble, etc. With regard to the food, it is interesting to note that although one rearer will find that sallow is excellent for the caterpillars, another considers that sallow or hawthorn are but poorsubstitutes for kidney-vetch (Anthyllis vulneraria) upon which the caterpillars were feeding when found (Plate57).
The brownish chrysalis is enclosed in a hard but somewhat brittle, brown, oval cocoon, and when spun upon the surface of the ground, protected by an outside covering of loose silk webbing. In August and early September the moths appear. Emergence from the chrysalis usually takes place soon after midday; the males are early on the wing, and when reared in captivity they should be secured as soon as the wings are dry, or they may spoil themselves in their efforts to escape. Reared females are apt to be deformed, but for "assembling" they may probably be as useful as more perfect examples if the rearer happens to be able to exhibit the attraction in a locality for the species. Both sexes have been taken at electric light.
The best known localities for the species in England are, besides those already mentioned, the sand hills on the Cheshire and Lancashire coast. It is, or has been, found also on the coast of Cumberland; Lyndhurst and Ringwood, in Hampshire; Isle of Purbeck, Poole, Swanage, and Bloxworth, in Dorsetshire; Devonport, Bolt Head, and Salcombe, in Devonshire; and Penzance and the Scilly Isles. Its range extends through Central and Southern Europe to Asia Minor and North Africa.
The male is reddish brown, and the female generally greyish brown, but sometimes is of a reddish grey coloration; the fore wings in both sexes are crossed by two pale ochreous lines on the central area (Plate59).
The ground colour in the male ranges in tone from foxy red to dullish red brown or to greyish red brown. The cross lines in either sex may be widely apart, near together, or even united throughout their length, forming a band (var.fasciata, Tutt); sometimes one of the lines (var.unilinea, Tutt), or both lines, are absent from the fore wings, or from one of them.
The brown clouded greyish eggs are laid in batches, during June, on stems and stalks of plants, or on heather; sometimes they have been found on a fence, a rock, or a stone. The caterpillars hatch out at the end of June and through July. At first they are black, including the glossy head, and covered with long hairs which are black with some white ones amongst them; the ring divisions are pale yellow; later on they are more chocolate brown with yellow bands which, however, do not encircle the body entirely.
When full grown, in the autumn, the caterpillar is velvety black, and above this colour is most in evidence between the rings; the back is clothed with dense, short, bright reddish brown or tawny hair, and the whole body is covered with brownish hairs, varying in length, but always much longer than the tawny ones; along each side are some whitish hairs. Head blackish covered with brownish hairs. It feeds in August and onwards to October, when it seeks winter quarters, reappearing in the following spring, but not feeding again. After enjoying the sunshine whenever the opportunity offers through the early months of the year, it finally pupates in March or April. The cocoon is a long, more or less tubular, brownish construction of silk and larval hairs. It is spun up, usually somewhat upright, low down among the food plant, or at the roots of grass, etc.; sometimes among moss, when the rounded head end can just be seen above the moss (Plate58).
In certain localities and seasons the caterpillars have been seen in enormous numbers, but such profusion only happens now and then. In some districts they may be abundant one year, and then scarce or quite absent for several years.
When handling the larvæ it will often be noted that the tips of one's fingers are thickly felted with the tawny hairs from the creature's back; if these hairs get transferred to the face or neck considerable irritation may be the result.
Plate 58
Plate 59
The late Mr. Robson used to collect the caterpillars on fine days in early spring, put each caterpillar into a separate paper box about two inches square, and keep them on a shelf over the kitchen fire, where they would duly pupate. Various methods for keeping these caterpillars through the winter have been described, and all appear to have been fairly successful. The most simple would seem to be the following: Bore a number of holes in the bottom of a roomy box, and fasten wire gauze on a close fitting frame to serve as a top. Cut a tuft or two of heather to cover the floor space of the box. Caterpillars collected in the autumn may be put into this receptacle and supplied with food, such as bramble or sallow, as long as they seem inclined to feed. Do not crowd too many into the box, and let it stand out in the garden, preferably on the soil.
The moths emerge in May or June. The males are very active on the wing in the afternoon sunshine, and later on, and may often be seen in numbers dashing hither and thither in an apparently erratic flight over heaths and open spaces, in search of the females. The latter do not fly till night, and occasionally they are attracted to a bright light.
Except that it has not been noted in the Shetlands, the species occurs throughout the British Isles. Abroad its range extends over Europe, and it is found in Amurland.
The male is reddish brown, more or less clouded on the forewings with ochreous; and the female is yellow, or whitish ochreous. Sometimes this colour distinction of the sexes is reversed, and the males are pale whilst the females are dark. In the fens of Cambridgeshire notably, pale or yellowish males are not altogether uncommon. Such specimens would seem to accord better with the Linnean type than the more usual form indicated above. Barrett mentions, among other aberrations, male specimens from South Wales with the whole of the fore and hind wings deep rich glossy purplish chocolate.
There is variation in the two whitish or silvery marks on the fore wings, the upper one is often very small, sometimes quite absent, and the lower one reduced to a crescent. The chocolate brown cross lines, of which there are usually two on the fore wings, are sometimes faint or entirely missing. Tutt has recently named nine forms, chiefly colour aberrations, and two others were previously named. (The moth is figured on Plate61, and the early stages on Plate60.)
The eggs, which are white with bluish grey markings, are laid in clusters on grass stems, etc.
The caterpillar is slaty grey inclining to blackish; the lines on the back are formed of yellowish dots and dashes; two rows of tufts of short black hairs on the back, with longer brown hairs between; low down on the sides are shaggy tufts of white and yellowish hairs and longer brown hairs; an erect pointed tuft of brown hair on second ring, and a similar one on ring eleven but the latter inclines backward. Head greyish, striped and lined with brown and yellowish brown, and clothed with brown hair. It feeds on coarse grasses, including the ribbon grass grown in gardens, in August to September or October.
In the latter month it goes into hibernation, being then but little over an inch in length. About April it resumes feeding and becomes full grown in June or thereabouts. The long yellowish or whitish brown cocoon in which it changes to a brown chrysalis is more or less pointed at the lower end, and generally attached to a culm of grass or a reed. A showery season seems to suit these caterpillars better than a hot, dry one. The partiality of the caterpillar for a drop of dew, mountain or otherwise, has frequently been noted. The old English name of The Drinker Caterpillar (1682) is therefore not only an appropriate one but shows that this larval habit was observed even at that early date. The specific namepotatoriagiven to the moth by Linné is of similar significance.
Plate 60
Plate 61
The moth emerges in July. It seems most addicted to damp grassy lanes, ditch-sides, fens, marshes, moorlands, and sandhills; and is not really uncommon in very many suitable districts throughout the United Kingdom. Abroad, it is common over the greater part of Europe and its range extends to Amurland and Japan.
This exceedingly local and rare British moth has the fore wings pale reddish-brown, suffused on the outer marginal area with grey; about the centre of the wings there is a short black line preceded by a whitish mark; beyond is a blackish, indistinct, wavy line; the greyish outer area is limited by a brown line, and this is inwardly edged with whitish: hind wings purplish brown with the central area whitish and crossed by a blackish line. Fringes whitish, marked with brown at the ends of the veins (Plate63).
Kirby states that the caterpillar is rust coloured, with a black stripe on the back, on which stand white dots; and with reddish-yellow transverse spots on the second and third rings. Another form is grey, and the back white, with a broad black central stripe interrupted by rust-coloured spots dotted with black.
The following brief description is taken from an inflated skin of an immature caterpillar received from Dresden: brownish inclining to reddish, paler between the rings; clothed with short greyish hair, and longer hairs from and above the fleshy tubercles low down along the sides; there is a hair-clothed eminence on ring eleven. The only conspicuous markings are on rings two and three; each of these has two orange spots separated and narrowly edged externally with velvety black; there are two small black spots on the back of each of the other rings, and indications of reddish circles around some of these. Head blackish, covered with greyish hairs (Plate62).
In this country the caterpillar feeds on bilberry (Vaccinium myrtillus), but on the Continent it is said to eat the foliage of sallows and willows, also of birch.
The cocoon is spun up among the leaves of the food plant. That figured on Plate62, of foreign origin, was on a shoot of bilberry; a moth emerged from it on April 5, 1907. The first detailed account of this species in Britain is that in theZoologistfor 1852, in which Mr. Atkinson records that he took a specimen in May, 1851, at Cannock Chase in Staffordshire. A year earlier two larvæ were found by Mr. Green on a moor near Sheffield, and one of these attained the moth state in April, 1851. After this moths and caterpillars seem to have been taken in varying numbers down to 1896, when a specimen was captured by Dr. R. Freer of Rugby. Tutt, quoting from a letter received from Dr. Freer, states that two moths were reared from three caterpillars found at Cannock in 1898. The only other known British locality is in the neighbourhood of Lynton, North Devon, where a caterpillar, which, from the description, must have been this species, was found in 1864. It was taken on August 3 in a wood abounding with bilberry.
The species ranges over Central Europe, but seems to be generally rare; it also occurs in Amurland and Japan.
Warm reddish brown is the prevailing colour of this fine moth. The wings are more or less suffused with purplish grey, and crossed by blackish lines—three on the fore wings and two on the hind wings. Except in the reddish tinge, which may be bright or dull approaching chocolate, this species is pretty constant in its coloration. Barrett mentions a specimen of a light brown colour, and another of a pale buff. The first of these forms seems to approach the var.meridionalis, Staudinger (Tutt), and the other to var.ulmifolia, Heuäcker, which are well known on the Continent. In certain favourable seasons a second generation of the moth has been obtained, chiefly perhaps, in confinement, and on the Continent; although in Britain a caterpillar or two will sometimes feed up and attain the perfect state the same year they hatch from the egg. These examples, which are much smaller, but do not otherwise differ from normal specimens, are referable to var.hoegei, Heuäcker.
Plate 62
Plate 63
The moth is figured on Plate63, and the eggs and caterpillar on Plate62.
The eggs, which are whitish in colour with greyish markings, are laid, in July or early August, in twos, threes, or more, on twigs or the undersides of leaves of sloe, apple, sallow, hawthorn, etc. A single female moth has been known to lay over a thousand eggs, but this is perhaps exceptional, and somewhere about half that number is possibly near the average. Even the latter would take the moth some time to distribute here and there in small batches.
The caterpillars hatch out in about a fortnight, feed for a few weeks, and in the autumn, when about three-quarters to one inch in length, take up their winter quarters low down on the stems of the food plant, but, in confinement, often on a withered leaf.
Caterpillar dark grey, so thickly sprinkled with minute black dots as to appear almost black; the whole body is clothed with fine and rather short blackish hair; low down on the side there is a fringe of brownish hair, and this covers the fleshy lappets (the older writers named this larva the "Caterpillar with the Lappets"); two white marks edged in front with black on the third ring, and a hairy prominence on the eleventh, are the most conspicuous features of this caterpillar. When the front rings are extended, the divisions between them are seen to be deep blue. Head grey, with darker stripe and paler lines. Occasionally several white marks appear on the back, and this is stated by Professor Poulton to occur more especially in the caterpillars when the twigs and stems of the food plant uponwhich they have grown up are covered with grey lichen. Sometimes the caterpillar has been reported as destructive in orchards; two or three large ones feeding on a small apple tree would certainly afford evidence of their presence in the shape of denuded twigs, but it is doubtful if they ever occur in sufficient numbers to cause any very serious damage to fruit trees.
The chrysalis is dark brown, inclining to blackish, and covered with a whitish powder, which does not shake off. It is enclosed in a long, grey-brown, tight-fitting cocoon of silk and hairs of the caterpillar, which is generally spun up among the lower twigs, or to the stem of the food plant.
The moth emerges in June or July, and is on the wing at night, when it may be sometimes netted as it flies along or over hedgerows. When caught in this way it dashes about so wildly in the net that it is rarely of much value for the collection. The same may be said of examples taken by light, which at times attracts the moths freely. When resting in the daytime, it very closely resembles a withered bramble-leaf or bunch of leaves. The fore wings are folded down, roof-like, over the hind wings, which are flattened out and their edges project beyond the margins of the fore wings. It is, however, very rarely seen in the open at such times.
The species does not seem to have been recorded from Ireland or from Scotland, but it has a wide distribution in England, although much less frequently met with in the north than in the south. In the Cambridge fens it is perhaps more plentiful than elsewhere, but it is not uncommon in some parts of Berkshire, Huntingdonshire, and Kent. The range abroad extends through Central, Southern, and Eastern Europe, to Armenia, Tartary, Siberia, and Amurland; it is also represented in China, Corea, and Japan.
Plate 64
Plate 65
This species has the fore wings of the male brownish clouded and suffused with ochreous; there is a white patch at the base, and some white marks including three spots towards the apex, on the outer marginal area; two black cross lines, the first inwardly and the second outwardly, edged with white; the space between the lines is sometimes clouded with whitish, and there is an almost central blacksideways vee-shaped mark. Hind wings tawny with a black central line, some brownish marks beyond, and sometimes two white spots at the upper angle. The female is much larger in size, without ochreous suffusion on the fore wings, and the hind wings have the ground colour whitish. It varies in the tone of the brown colour, and, in the male, in the amount of ochreous suffusion (Plate65).
The eggs are laid in rows, generally two deep, on a birch twig. At first they are greenish, but soon change to brownish olive or shining purplish brown.
When young the caterpillars cluster together on the twigs, as shown on Plate64. They are at first black with glossy dots, and later, greenish, but still dotted with black. After the third skin change, they are without the black dots, and the colour is then pretty much that of the mature caterpillar, which is green, rather whitish on the back, and with a dark green central line; a series of seven creamy oblique stripes along the sides, and on the sides of the first three rings there is a whitish stripe broken at the divisions; these markings are often edged with dark green; on the eleventh ring there is a somewhat horn-like prominence, striped with creamy white, and below it a yellow stripe; the spiracles are white, ringed with black. Head small, paler green, with whitish marks. Feeds on birch, from late May toJuly. Alder, sallow, and lime have also been mentioned as food plants.
The rough, blackish, or sooty-brown chrysalis is enclosed in a coarse netted cocoon, dark brown in colour, and more or less covered with moss, leaves, or other material, among which it is spun up, generally on the ground, but sometimes just under the surface. Assisted by the points on the rings of the body, the chrysalis is able to work itself partly out of the cocoon, and this it does some days before the moth emerges.
The moths usually emerge in late March and in April, earlier or later in some seasons. They do not always come up the year after pupation, but often remain two or more winters in the chrysalis.
The males fly in the sunshine, and are very strong on the wing; the females are not active until dark. This sex has been found resting on the twigs of birch, also on heather, and occasionally on a tree trunk. The males "assemble" freely to a freshly emerged female. The species inhabits the more open parts of woods and forests, moors and hillsides where birches flourish. It is probably more plentiful in its Scottish localities, such as Rannoch and Forres, than elsewhere, but it occurs also in Aberdeenshire, Kincardineshire, and Argyllshire. In England it seems to be not uncommon in Wyre Forest, Worcestershire, and the Reading district in Berkshire. It used to be so plentiful in Tilgate Forest, Sussex, that over a hundred males were brought to the net in one day by a bred female put down to allure them. This happened some fifty years ago, and compares curiously with a record of one male attracted by a female in Tilgate Forest, April 13, 1869. Other localities in Sussex that have been mentioned are St. Leonard's Forest and near Petersfield; it has also been found in Herefordshire and in some parts of Suffolk. Distributed over Central and Northern Europe, the range extending to North Italy.
Plate 66
Plate 67
In a general way the fore wings of the male may be described as purplish grey, suffused with rosy or with tawny shades; a reddish cloud, black marked above, at the tips of the wings; the outer margins are more or less whitish, and there is a whitish patch about the middle of each wing, in which is an eyed spot; the hind wings are tawny, with a central eye spot and a blackish band towards the outer margin. The female has all the wings pale purplish grey, with whitish bordered outer margins; markings much as in the male, but the central area of the hindwings is more or less whitish. There is some variation in the ornamentation; occasionally the white markings are of large size, or, on the other hand, may be almost or quite obscured. Very rarely the eye-spots are absent from all the wings (ab.obsoleta, Tutt), and sometimes they are of abnormal shape. Now and then specimens of the female sex are dark in colour, with red bands, and Barrett mentions an example of this sex smoky black in colour, with still blacker markings (Plate66).
The olive brown, clouded greyish eggs are laid in neatly arranged batches around the stems or twigs of plants; I once found a batch in North Devon on a loose piece of rock. The caterpillar when full grown is bright green, with black markings; the warts from which blackish bristles arise are yellow, sometimes pink or blackish. In an early stage it is black, with an orange line low down along the sides; later on it is still black, but ringed with orange. It feeds in June, July, and August on many kinds of plants, among which may be mentioned heather, bramble, sallow, sloe; also meadow-sweet (Spiræa ulmaria) and purple loose-strife (Lythrum salicaria).
The curious cocoon formed by the caterpillar (Plate67) isso constructed at the narrow end that the moth on emergence can easily pass through; after the insect's escape, the converging fibres forming the "door" spring to again, and the point of exit looks pretty much as before the moth had pushed through. This kind of opening can only be worked from the inside, therefore enemies from without are unable to effect an entrance.
The moths are out in April and May, and the males may be seen on sunny days flying at a great pace over heaths, moorlands, and mosses, also about the borders of woods. The female flies at night, but it may occasionally be met with resting on heather or other herbage in the daytime. A freshly emerged female moth will, as a rule, attract as many specimens of the opposite sex as one would care to take; all that one has to do is to take her in a box to some likely spot, and there await the coming of the males.
The species seems to be generally distributed throughout the British Isles, but is commoner in some parts than in others, and apparently rare in portions of the Midlands.
The distribution abroad extends through Europe to North Asia Minor and Armenia, and to Siberia, Amurland, and Ussuri.
The British species belonging to this family, with one exception, have the tips of the fore wings pointed and curved downwards, forming a sort of hook, hence the English name Hook-tips. The exception isCilix spinula, a round winged moth, not at all like other members of the family, but its caterpillar is very like others of the group.
The bristle and catch arrangement for locking the wings is present in all the species, but the tongue or proboscis is absent, or practically so. The caterpillars are not furnished with analclaspers, therefore have only fourteen legs, that is, six true legs and eight false legs (pro-legs). The last ring of the body is more or less tapered, sometimes terminating in a point; the back is roughened with raised spots and warts, or humped. They feed on the leaves of trees and bushes, usually exposed, and they pupate in a silken cocoon, spun up between leaves, or in a folded leaf, of the food plant.
Of the eleven species occurring in the Palæarctic Region, seven are European, and six of these are found in the British Isles.
The fore wings are brown, whity brown, or whitish; the central area is crossed by three blackish wavy lines, a blackish blotch in the third line and two blackish dots between it and the second line; beyond there is a dark brown, or reddish-brown curved line from the tip of the wing to the inner margin. Hind wings similar in colour to the fore wings, but paler on the front area; crossed by five wavy dusky lines, sometimes not well marked except on the inner margin; generally, there is a black central dot. The paler forms have a dusky shading on each side of the curved line on the fore wings.
The egg is yellow freckled with orange, chiefly at one end. Caterpillar green, the back reddish-brown, except towards the black-marked yellowish head; two conspicuous warts on rings two to five, and less noticeable raised spots on the other rings, all bearing hairs. In a younger stage it is blackish, with white marks on the fourth and seventh rings; later it becomes greenish below, and the markings on the back of rings four, seven, eight, and ten are whitish or creamy. Until nearly full grown it usually lives on the underside of a leaf, the edges of which are turned over and held down by silken threads; sometimes it may be seen on the upper side of a leaf under a slight web. It feedschiefly on birch, but is occasionally found on alder, in June and July, and in September and October, and may be obtained by searching or by beating, but the former, although perhaps slower, is much the better method. The moth is shown on Plate68, and the early stages on Plate69.
The species is widely distributed, and seems to occur, sometimes commonly, wherever there are birches, especially of bush-like growth, in most English counties and also in Scotland. In Ireland it appears to be somewhat local and scarce.
The general colour of this species is brownish; the fore wings are slightly tinged with ochreous and speckled with minute violet-tinged silvery scales; between the first and second brown lines there is an irregular ochreous brown mark enclosing yellowish spots; the violet-tinted glistening scales are most in evidence on both sides of the black mark before the outer margin. Hind wings similar in colour to the fore wings; crossed by two brown lines, the second with an ochreous brown blotch above it (Plate68).
Caterpillar, yellow freckled with brown; clouded with brown on first three rings; a reddish brown irregular stripe runs along the sides and upwards towards middle of the back on rings five, six, eight, and nine; a double-pointed hump on the back of ring three, the points tipped with yellow. Head notched on the crown, dotted and clouded with brown. It feeds on the small-leaved lime (Tilia parvifolia), and may be found from July to September and even later. I have not seen a living caterpillar of this species; the above short description has been drawn from an inflated skin (Plate69).
The only British locality for this species is the Leigh Woods near Bristol, where it was first met with in 1837. It is, however, very rare and difficult to obtain. Abroad it ranges through Central Europe to Livonia, Southern Sweden, and to Northern Italy. On the Continent the caterpillar feeds on the foliage of other trees than lime, and there are two broods in the year.
Plate 68
Plate 69
The male is of an ochreous-tinged brown coloration; all the wings are crossed by two slender deep ochreous lines, and have two obliquely set, almost central, black dots; outer margin of fore wings often blackish, marked towards the tip; the hind wings are deep ochreous on the front marginal area. Fore wings of the female paler, and the hind wings ochreous yellow; the cross lines on the latter often lost in the ground colour (Plate71).