The Moths of the British Isles Volume I Part 19

BUFF ERMINE MOTH _and varieties_.

{151} The moth, which emerges in June, is rarely seen away from its favourite haunts, which are marshes and fens; its English name is therefore a very appropriate one. It is not often observed in the daytime, but is on the wing early in the evening, and later on is pretty sure to be attracted to any strong light that may be set up in its neighbourhood. The best localities for the species seem to be the fens of Norfolk and Cambridge, but it used to be fairly plentiful in many suitable parts of East Kent, and no doubt still occurs in some of the marshes between Dartford and Gravesend: it is found in Suss.e.x in the Lewes and Brighton districts, and has been recorded from Kimmeridge in Dorsets.h.i.+re, from the Isle of Wight, from near Burton-on-Trent, from the Lancaster district, and from Pembrokes.h.i.+re, South Wales. In Scotland it is rare, and, with the exception of one example reported as taken in an illuminated moth trap at Clonbrock, May, 1896, not known to occur in Ireland.

The distribution abroad extends over Central and Northern Europe, through South Russia to Amurland.

THE BUFF ERMINE (_Spilosoma lubricipeda_).

This species is now known by the English name of the Buff Ermine, but the names bestowed upon it by some ancient writers were perhaps hardly more suitable. Thus Wilkes in 1773 called it the "Spotted Buff Moth," and Harris five years later dubbed it the "Cream-dot Stripe." The ground colour is generally some shade of buff, in the paler specimens merging into cream, and in the darker to yellowish ochre. In the matter of black marking the range of variation is extensive. The specimens figured on Plate 77 ill.u.s.trate something of this variation, both as regards colouring and marking. The females are, as a rule, paler than the males, but occasionally examples {152} of the latter s.e.x are quite as pale as any female. Figures 7 and 8 represent var. _zatima_, Cramer. Originally this form was only known to occur in Heligoland. The same form, or a modification of it, was described by Haworth as _radiata_, from a Yorks.h.i.+re specimen. Then, in 1837, specimens of the variety were reared with the normal form of the species from caterpillars obtained at Saltfleet in Lincolns.h.i.+re; and subsequently a few more examples were reported from the last named county, and elsewhere. In 1891 a specimen of var. _zatima_ emerged from an a.s.sortment of chrysalids sent to Mr. Harrison of Barnsley from a London correspondent. This particular specimen was of the female s.e.x, and it paired with a male which was also an aberration, but not of the _zatima_ form. Some of the offspring resulting from this union were of the female parent form, others favoured the male parent, and others again were intermediate. In the course of a few generations almost entire broods of the _zatima_ variety were obtained. Allowing the s.e.xes of _zatima_ to mate with those of more or less ordinary _lubricipeda_, the late Mr. W. H.

Tugwell obtained many very interesting aberrations, one of which he named var. _eboraci_, and another _fasciata_. The _zatima_ form and its various modifications have now been reared by entomologists all over the country, and presumably directly or indirectly from the original Barnsley stock. In Yorks.h.i.+re especially the race has been improved; the specimens are larger and darker, and there is a tendency towards the almost entirely black form known as var. _deschangei_.

The pale whitish green eggs are laid in batches on leaves, sometimes high up on birch trees, or virginia creeper, but more usually on the foliage of low growing plants; it is often common in gardens. At first the caterpillar is tinged with yellowish, but it afterwards becomes greyish, and finally brownish. When full grown the hairs, with which the body is clothed, are brown; there is a yellowish or whitish grey stripe along each side, and an obscure somewhat reddish {153} tinted line down the middle of the back.

Head glossy brown.

The glossy reddish-brown chrysalis is enclosed in a dingy coloured web-like coc.o.o.n, which is spun up among leaves or litter on the ground. Mr. R. Adkin found some of these coc.o.o.ns spun up between the folds of an old brown blanket used as a covering for a rabbit hutch in winter. The moth emerges in June. Occasionally, in confinement, specimens will leave the chrysalis in the autumn instead of pa.s.sing the winter therein, as they more usually do (Plate 76).

A common and often abundant species over the greater part of the British Isles. Its range abroad extends through Central and Northern Europe, South Russia, and Tartary to Amurland, Corea, and West China.

THE MUSLIN (_Diaphora mendica_).

The early British authors knew this moth as the "Spotted Muslin" or "Seven Spot Ermine" (Harris, 1778). The male is dark brown or blackish, with a few usually obscure black dots on each wing. The female is silky white, with more clearly defined, and often more numerous, black dots (Plate 75, Figs.

4-6). On Plate 78 will be found figures of the rarer and more extreme aberrations of the female. Those represented by Figs. 3, 4, 6, 7, were reared some years ago by Mr. G. T. Porritt, of Huddersfield, who at the same time obtained a number of other interesting intermediate examples ("Trans. Ent. Soc. Lond.," 1889, p. 441, Pl. 14). Variation in the other direction is towards the complete suppression of the black dots; and I have seen specimens with only one such dot on each wing.

In the var. _rustica_, shown on the same plate, it will be noted that the males a.s.similate somewhat to the female coloration; the specimens (Figs. 1, 2), were bred by Mr. Robert Adkin in 1887. This form was not known to occur in the British {154} Isles until 1885, when Mr. de V. Kane detected specimens in a collection of insects made in Co. Cork, Ireland. It was next heard of from Belfast, and then, in 1886, again, in Co. Cork, an example of each s.e.x was taken. The female specimen laid eggs, and some of these were sent to Mr. Adkin, who not only was successful in rearing the moths, but in 1889 obtained a pairing between an almost white male _rustica_ and an ordinary English female. Only four eggs were laid, and from these two male moths resulted in May, 1890, both intermediate in colour between the two forms. In all its early stages _rustica_ is identical with ordinary _mendica_.

Male specimens with pale yellowish grey coloured wings have been reared from eggs laid by a female captured at Eltham, Kent, exhibiting a tendency to the _rustica_ form. In the Barnsley district, Yorks.h.i.+re, the males are paler than usual, but in the Sheffield area of the same county the males are black. From North Durham chrysalids, I have a smoky greyish form of the male.

The caterpillar is brownish grey covered with yellowish brown hairs arising from greyish-ringed pale brown warts; a paler line along the middle of the back, and some white dots forming a broken line below the black outlined spiracles. Head pale chestnut brown, glossy. When newly hatched it is whitish, tinged with yellow and semi-transparent; the dots and hairs are dark grey. After the first moult the colour is greyish with black dots and blackish hairs. Head yellowish, brown tinged. It feeds in July, sometimes earlier, and August, and seems to thrive on the foliage of many kinds of low-growing plants, such as dandelion, dock, plantain, chickweed, etc., and also eats the leaves of birch and rose. Chrysalis, very dark brown, almost black, glossy, but minutely pitted, giving a roughened appearance; enclosed in a close fitting coc.o.o.n composed of silk and the caterpillar's hairs, with particles of earth on the outside (Plate 79). The moth flies at night, and except that a female may occasionally be seen on the wing, this species is rarely observed in the daytime. May and June are the usual months for this moth, but in 1906 a specimen was attracted to light on November 3.

[Ill.u.s.tration]

Pl. 78.

1, 2, 3, 4, 6, 7. MUSLIN MOTH _varieties_.

5. WHITE ERMINE, _var. walkeri_.

[Ill.u.s.tration]

Pl. 79.

MUSLIN MOTH.

_Eggs, natural size and enlarged; caterpillar, chrysalis and coc.o.o.n._

{155} Widely distributed, and often common in most English counties, in parts of Wales, and in Scotland as far north at least as Ross. In Ireland one male specimen of the typical form has been obtained in Co. Galway, and one in Co. Clare; var. _rustica_ occurs in Co. Dublin, and Kings Co., Waterford, Cork, Kerry, and Galway.

THE RUBY TIGER (_Phragmatobia fuliginosa_).

The English name given to this moth only suitably applies to the southern reddish form of the species (Plate 80, Fig. 1 [male]). In the north of England the fore wings are darkened with brownish and the hind wings with blackish tints, until in Scotland the only trace of red colour is found on the inner edge of the hind wings (var. _borealis_, Staudinger, Fig. 2 [female]). In these dark specimens the body is also blackish. Very occasionally, specimens approaching the northern form are obtained in South England. A female moth captured by Mr. G. E. J. Crallan in May, 1901, at Bournemouth, laid forty-eight eggs; thirty imagines were bred the same year, two of which were _borealis_. On the south and south-west coasts the black band of the hind wings exhibit a tendency to break up into spots; not infrequently this is completely effected, and the specimens then approach the larger South European form var. _fervida_, Staud. In a fine series of this species from Cornwall, lately seen in Mr. A. Harrison's collection, are a few specimens that come very close to the last-named form. A yellow aberration has been recorded. The eggs are whitish and deposited in batches on leaves. Up to the last moult the caterpillar is greyish or brownish, with dark greyish or blackish {156} warts from which arise star-like tufts of brown hairs; a reddish line along the middle of the back, and some reddish spots on the sides. When full grown it is black, and the reddish line on the back is almost hidden by closer and more compact tufts of black hairs. Head black and glossy.

The leaves of various low-growing plants afford it nourishment, but it is very partial to dock, dandelion, golden-rod (_Solidago_), and plantain; it is also fond of groundsel and lettuce in confinement, but these plants have been found unsuitable if given too frequently. In the open it seems to feed through the summer, hibernate when full grown, reappear in the early spring, and in due course spin its brownish coc.o.o.n among herbage generally low down near the ground; on moors it often makes the coc.o.o.n among the twigs of heather as shown on Plate 81. The chrysalis is black, marked with yellowish on the hind edge of each ring. The vitality of the caterpillar is extraordinary. One known to have been embedded in ice for fourteen days at least, became active in less than half an hour after the ice around it melted. It pupated shortly afterwards.

When eggs are obtained early, it is possible to have three generations of the moth during the same year. Thus eggs deposited on May 8 produced caterpillars which fed up quickly and attained the moth state in July. From July eggs some of the caterpillars will outstrip their companions, pupate in September, and appear as moths about a month later. The moth is to be found in May and June, sometimes in July or August, in wood clearings, on moors and rough hillsides, and also in water meadows, etc. It flies at night, is attracted by light, and although it occasionally flies in the suns.h.i.+ne, it is, as a rule, not often seen in the daytime. Occurs throughout the British Isles to the Orkneys. Distribution: Europe, Western and Central Asia, Amurland, j.a.pan, North-west Africa, North America.

[Ill.u.s.tration]

Pl. 80.

1, 2. RUBY TIGER MOTH.

3, 4, 5, 6, 7. WOOD TIGER MOTH.

[Ill.u.s.tration]

Pl. 81.

1, 1a. WOOD TIGER: _eggs and caterpillars_.

2, 2a. RUBY TIGER: _caterpillar and coc.o.o.n_.

{157}

THE WOOD TIGER (_Parasemia plantaginis_).

On Plate 80 are shown some of the forms of this attractive and somewhat variable species. Figs. 3, 4, are male and female of the typical form found in England. The most usual phase of variation is in the narrowing or widening of the pale yellowish markings of the fore wings, and the black markings on the hind wings; occasionally the yellow or the black increases to such an extent that the fore wings appear to be almost entirely of the one colour or the other. The hind wings range in colour from the normal yellow through orange to red, and through pale shades of yellow to white; on the other hand they are sometimes almost entirely black. The var.

_hospita_, Schiff. (Fig. 7), has all the wings white, and although it has been reported from Shrops.h.i.+re, West Durham, the Lake District, etc., it has been chiefly obtained in the Hebrides and in the highlands of Scotland.

Only males of this form are known; the females found with them have heavy black markings on the hind wings, almost crowding out the reddish ground colour. The creamy markings of the fore wings are narrow, and the central spot small.

The full-grown caterpillar is blackish above with greyish-black warts from which arise tufts of blackish hairs, except on rings four to six, where the hairs and the warts at the base of each tuft are reddish; the black hairs of the hinder tufts are the longest (Plate 81).

Twelve eggs laid by a female in Aberdeens.h.i.+re were received on June 29, 1906. They were s.h.i.+ning yellowish in colour, and were on a leaf of plantain. The caterpillars resulting from these eggs were reared on a mixed diet of forget-me-not (_Myosotis_), plantain, and groundsel, but evinced a decided preference for the former. Some died young in moulting, but at the beginning of August five were full grown, and four duly pupated in a slight but roomy coc.o.o.n of silk, mixed with the caterpillar's hairs, {158} in which the blackish brown chrysalis with the cast-off skin attached to the tail was plainly visible. Four moths, all female, emerged at the end of August, when the other caterpillar was still feeding, and seemingly about mature. That caterpillar did not, however, pupate, or survive the winter.

As a rule the caterpillars hibernate when about half grown, and feed up in April and May of the following year. The somewhat unusual rate at which those just mentioned completed their growth was no doubt due to the heat of the summer of 1906.

The moth is to be found on heaths, moors, the slopes of chalk, and limestone hills; also in woods that are not too thickly timbered and have a good undergrowth of heather, etc. The males may sometimes be seen flying in the suns.h.i.+ne, and they will then be noted to wing their way to some particular spot where most likely a freshly emerged female will be the attraction. The male is often started up from the heather or other herbage as one walks along; or it may even rise from the bare ground upon which it sometimes has a fancy to sit. The female seems to be more sluggish during the daytime.

The species is widely distributed over the British Isles, and its range extends through Central and Northern Europe, and Northern Asia to j.a.pan.

THE CLOUDED BUFF (_Diacrisia sanio_).

Fore wings of the male yellow, with a reddish and greyish central mark; hind wings whitish, with blackish central spot and outer band; the inner margin, fringes, and front edge light crimson. The female has orange fore wings with reddish margins, veins, and central mark; hind wings orange, with black basal area, central spot, and outer band (Plate 82).

The female of this species is so different in appearance from the male that it was described by Linnaeus as distinct, under the name _russula_. In the tenth edition of "Systema Naturae" it is {159} No. 510, whereas _sanio_, the male, is No. 506. We must, therefore, in accordance with the law of priority, adopt the earliest name for the species, however much we regret having to discard the old familiar name of _russula_.

Although the central spot of the fore wings is subject to minor modification in size, shape, and colour, it is in the hind wings that variation chiefly occurs. In the male the blackish grey band on the outer area of the hind wing may be broad and complete, or it may be broken up by the veins into a series of bars; then, again, the bars tend to become smaller and smaller until only tiny portions remain. Usually, the basal third of the hind wings is more or less greyish, but sometimes the whole surface almost, or quite up to the outer band, is clouded with dark grey.

The black markings of the female hind wings are apt to vary in a very similar way.

The caterpillar is reddish brown, covered with brown hairs; a yellow-marked whitish stripe along the back, and two darkish stripes on the sides; a white spot below each black margined spiracle. It hatches from the egg in July, and as a rule hibernates when still small, completing growth in April and May. It feeds on the leaves of many low plants, among which are dandelion, dock, chickweed, and plantain. The chrysalis is brown, streaked with greyish, and is enclosed in a flimsy coc.o.o.n among herbage, generally on the ground.

The moth, which inhabits heaths and mosses, is on the wing in June and early July; the male may be put up on sunny days, but the female is not often seen until early evening. After dark both s.e.xes may be found on the heather.

It should be noted here that there are usually two broods of this species abroad, and that in confinement it will develop a more or less complete second brood in September with us. An instance is recorded of sixty-three out of sixty-six caterpillars from eggs laid in early July, feeding up and producing moths in the last week of September. The caterpillar is not an easy one {160} to deal with during hibernation, so that it would always be to the advantage of the rearer to get it through to the perfect state the same year, whenever possible.

The species is widely distributed over the south and east of England, and South Wales. It occurs in Ches.h.i.+re in all suitable places; in Lancas.h.i.+re it is common on the moorlands, as at Witherslack and Methop, and it is not uncommon near Quernmore, Clougha, and other places, in July. Local and somewhat scarce as a rule in Yorks.h.i.+re, but recorded as not uncommon in the Scarborough district. In Scotland it is found in Roxburghs.h.i.+re, and northwards to Aberdeen; and, according to Kane, it is widely spread, although local, in Ireland.

THE GARDEN TIGER (_Arctia caia_).

How frequently the collector has had introduced to his notice, by some non-entomological friend, or worthy cottage dame, a "fine b.u.t.terfly," only to find that the supposed prize, usually imprisoned under an inverted tumbler, was just an ordinary specimen of the gaudy, but common, Garden Tiger. Few persons living in the country, and at all interested in the natural objects around them, will fail to recognize the portraits on Plate 82; other figures, however, on Plate 84 will appear strange, and yet they only portray some of the many forms which the moths a.s.sume. Possibly it would be true to say that no two specimens could be found that were exactly identical in tint and marking. Even the markings of any one example are frequently not precisely alike on corresponding wings. Normally the fore wings are white or creamy-white with dark brown markings, and the hind wings are red with deep blue centred black spots, often ringed with yellow.