Chapter IV: Part II: Descriptions of Species (1)

The Swallow-tail (_Papilio machaon_).

The Swallow-tail butterfly is the only British member of the extensive and universally distributed sub-family Papilioninæ, which includes some of the largest as well as the most handsome kinds of butterfly. Our species has yellow wings ornamented with black, blue, and red, and is an exceedingly attractive insect. The black markings are chiefly a large patch at the base of the fore wings, this is powdered with yellow scales; a band, also powdered with yellow, runs along the outer or hind portion of all the wings. There are also three black spots on the front or costal margin, and the veins are black. The bands vary in width, and that on the hind wings is usually clouded more or less with blue. At the lower angle of the hind wings there is a somewhat round patch of red, and occasionally there are splashes of red on the yellow crescents beyond the band. The male and female are shown on Plate 2.

The eggs are laid on leaflets of the milk parsley (_Peucedanum palustre_), which in the fenny home of the butterfly is perhaps the chief food-plant of the caterpillar. This is one of the few eggs of British butterflies that I have not seen. Buckler says that it is globular in shape, of good size, greenish yellow in colour when first laid, quickly turning to green, and afterwards becoming purplish.

The caterpillar when full grown, as figured on Plate 1, is bright green with an orange-spotted black band on each ring of the body, and blackish tinged with bluish between the rings. The head is yellow striped with black. When it first leaves the egg-shell, which it eats, the caterpillar is black with a noticeable white patch about the middle of the body. After the third change of skin it assumes the green colour, and at the same time a remarkable =V=-shaped fleshy structure of a pinkish or orange colour is developed. This is the _osmaterium_, and is said to emit a strong smell, which has been compared to that of a decaying pine-apple. The organ, which is extended in the figure of the full-grown caterpillar, is not always in evidence, but when the caterpillar is annoyed the forked arrangement makes its appearance from a fold in the forepart of the ring nearest the head. Other food-plants besides milk parsley are angelica (_Angelica sylvestris_), fennel (_Foeniculum vulgare_), wild carrot (_Daucus carota_), etc. From eggs laid in May or June caterpillars hatch in from ten to twelve days, and these attain the chrysalis state in about six or seven weeks. If the season is a favourable one, that is fine and warm, some of the butterflies should appear in August, the others remaining in the chrysalids until May or June of the following year; a few may even pass a second winter in the chrysalis. Caterpillars from eggs laid by the August females may be found in September, nearly or quite full grown, and chrysalids from October onwards throughout the winter. They are most frequently seen on the stems of reeds, but they may also be found on stems or sprays of the food-plants, as well as on bits of stick, etc. It would, however, be practically useless to search for the late chrysalids as the reeds are usually cut down in October, when the fenmen keep a sharp look-out for them, and few are likely to escape detection in any place that would be accessible to the entomologist.

=Swallow-tail Butterfly.=

1 _male_; 2 _female_.]

=Black-veined White Butterfly.=

_Eggs, natural size and enlarged; caterpillar and chrysalis._]

On Plate 1 three forms of the chrysalis are shown. The figures are drawn from specimens collected in Wicken Fen in October, 1905. Occasionally a much darker, nearly black, form is found.

This butterfly was known to Petiver and other early eighteenth-century entomologists as the Royal William. There is every reason to believe that at one time it was far more widely distributed in England than it now is. Stephens, writing in 1827, states that it was formerly abundant at Westerham, and gives several other localities, some very near to London.

During the last twenty-five years or so, the butterfly has been seen on the wing, from time to time, in various parts of the Southern and Midland counties. Caterpillars have also been found at large in Kent. Possibly attempts may have been made to establish the species in certain parts of England, and the presence of odd specimens in strange places may thus be accounted for. Or such butterflies may have escaped from some one who had reared them.

On the Continent the butterfly is common in woods as well as in meadows, and even on mountains up to an elevation of 5000 feet. It occurs also, but less commonly, at much higher altitudes. It therefore seems strange that in England it should be confined to the low-lying fens of Norfolk and Cambridgeshire. Such is the case, however, and a journey to one or other of its localities will have to be made by those who wish to see this beautiful creature in its English home.

It may be added that the geographical range of the butterfly extends eastwards through Asia as far as Japan. A form, known as the Alaskan Swallow-tail, is found in Alaska.

* * * * *

The following ten species belong to the Pierinæ, another sub-family of Papilionidæ.

The Black-veined White (_Aporia cratægi_).

The Black-veined White (Plate 4) may be at once recognized by its roundish white wings and their conspicuous veins, which latter are black in the male butterfly, and in the female brownish on the main ones (nervures) and black on the branches (nervules). As the scales on the wings are denser in the male than in the female, the former always appears to be the whiter insect. On the outer margin of the fore wings there are more or less triangular patches of dusky scales, and these in occasional specimens are so large that their edges almost or quite meet, and so form an irregular, dusky border to the fore wings. These patches are also present on the hind wings, but are not so well defined. Sometimes the patches are absent from all the wings. The fringes of the wings are so short that they appear to be wanting altogether. The early stages are figured on Plate 3.

The egg is upright and ribbed from about the middle to the curiously ornamented top, which appears to be furnished with a sort of coronet. The colour is at first honey-yellow, then darker yellow, and just before the caterpillar hatches, greyish. The eggs are laid in a cluster on the upper side of a leaf of sloe, hawthorn, or plum, etc., in the month of July.

The caterpillar when full grown is tawny brown with paler hairs arising from white warts; the stripes along the sides and back are black. The under parts are greyish. The head, legs, and spiracles are blackish. Caterpillars hatch from the egg in August, and then live together in a common habitation which is formed of silk and whitish in colour. They come out in the morning and again in the evening to feed, but a few leaves are generally enclosed in their tenement. In October they seem to retire for the winter and reappear in the spring. During May they become full grown and then enter the chrysalis state. The butterflies are on the wing at the end of June and in July.

=Black-veined White Butterfly.=

1, 2 _male_; 3, 4 _female_.]

=Large White Butterfly.=

_Eggs, natural size and enlarged; caterpillar and chrysalids._]

The chrysalis is creamy white, sometimes tinged with greenish, and dotted with black.

This butterfly was mentioned as English by Merret in 1667, and by Ray in 1710. Albin in 1731, who wrote of it as the White Butterfly with black veins, figures the caterpillar and the chrysalis, and states that caterpillars found by him in April turned to chrysalids early in May and to butterflies in June. Moses Harris in 1775 gave a more extended account of the butterfly's life-history, and what he then wrote seems to tally almost exactly with what is known of its habits to-day. This species has seemingly always been somewhat uncertain in its appearance in England. Authors from Haworth (1803) to Stephens (1827) mention Chelsea, Coombe Wood in Surrey, and Muswell Hill in Middlesex, among other localities for the butterfly. It has also been recorded at one time or another, between 1844 and 1872, from many of the Midland and Southern counties. In 1867 it was found in large numbers, about mid-summer, in hay fields in Monmouthshire. The latest information concerning the appearance of the species in South Wales relates to the year 1893, when several caterpillars and four butterflies were noted on May 22 in the Newport district. At one time it was not uncommon in the New Forest, but no captures of the butterfly in Hampshire have been recorded during the last quarter of a century. At the present time it is probably most regularly obtained in a Kentish locality, presumably in the Isle of Thanet, which is only known to a few collectors. It may be mentioned that some thirty years ago caterpillars of the Black-veined White could be obtained from a Canterbury dealer at a few shillings per gross.

The species is widely distributed, and often abundant, on the Continent, and its range extends through Western and Northern Asia to Yesso, Northern Japan.

The Large White (_Pieris brassicæ_).

This butterfly is probably almost as familiar to those who dwell in towns as it must be to those who live in the country. It is perhaps unnecessary to describe it in any detail, and it may therefore suffice to say that it is white with rather broad black tips to the fore wings; there are some black scales along the front margin of these wings, and on the basal area of all the wings. The male has a black spot on the front margin of the hind wings, and the female has, in addition, two roundish black spots on the fore wings, with a black dash from the lower one along the inner margin.

As there is a rather important difference between the specimens of the spring (_vernal_) and the summer (_æstival_) broods, figures of a male and a female of each brood, and showing the upper and under sides, are given. Those on Plate 6 represent the spring form, which was at one time considered to be a distinct species, and named _chariclea_ by Stephens. Plate 9 shows the summer form. The chief point of difference is to be noted in the tips of the fore wings, which in the spring butterflies are usually, but not invariably, greyish; in the summer butterflies the tips are black, as a rule, but not in every case.

Occasionally the black on tip of the fore wing in the female is increased in width, and from it streaks project inwards towards the upper discal spot. In some examples of the male there is a more or less distinct blackish spot on the disc of the fore wings. Very rarely the ground colour is creamy or sulphur tinted.

The greenish tinge about the veins, sometimes seen in these butterflies, is due to some accidental cause, probably injury to the veins.

=Large White Butterfly (Spring Brood)=

1, 2 _male_; 3, 4 _female_.]

=Small White Butterfly=

_Resting._]

The egg is yellowish in colour, somewhat skittle-shaped, and very prettily ribbed and reticulated. On Plate 5 there are two figures of the egg from enlarged drawings by Herr Max Gillmer, to whom I am greatly indebted for the loan of them. In the figure on the right, the dark spot at the shoulder of the egg represents the head of the young caterpillar, and in that on the left is seen the caterpillar about to come out of the egg. The head is already out, and the jaws have left their mark on the egg-shell. Most caterpillars of the Whites, as well as those of other butterflies, devour their egg-shells.

The eggs are laid in batches of from six to over one hundred in each batch. They are placed on end, and on either side of a leaf, chiefly cabbage. Herr Gillmer writes that he watched a female depositing her eggs on a leaf of white cabbage in the hot sunshine, and found that she laid twenty-seven in about nine minutes. A previous observer had timed a female, and noted that she produced eggs at the rate of about four in the minute. Caterpillars hatch from the egg in about seven days in the summer. The caterpillar (Plate 5) when full grown is green tinged with blue or grey above, and greenish beneath. There are numerous short whitish hairs arising from little warts on the back and sides; the lines are yellow. The caterpillars feed in July, and sometimes again in September and October, on all plants of the cabbage tribe, and also on tropæolum and mignonette. A number of these caterpillars may often be seen crowded together on a cabbage leaf, and they sometimes abound to such an extent that much loss is sustained by growers of this most useful vegetable. A peculiarity of these caterpillars is that even when not numerous, their presence is indicated by an evil smell that proceeds from them. The unpleasantness of the odour is greatly intensified if the caterpillars are trodden upon.

The chrysalis (Plate 5) is of a grey colour, more or less spotted with black and streaked with yellow. It is often to be seen fixed horizontally under the copings of walls, the top bar of a fence, or a window-sill; but it sometimes affects the upright position when fastened in the angle formed by two pales. A position that affords some measure of protection from weather is generally selected.

Although this butterfly is almost annually to be seen, in greater or lesser numbers, throughout the country, it is occasionally scarce, either generally or in some parts of the British Islands. For example, during the past year (1905) it was abnormally plentiful in Ireland, but at the same time comparatively rare in England. It is a migratory species, and no doubt its abundance in any year in these islands is dependent on the arrival of a large number of immigrants. Possibly in some years none of the migrant butterflies reach our shores, and that it is largely to this failure the rarity of the species in such years is to be attributed. Caterpillars resulting from alien butterflies may absolutely swarm in the autumn of one year, but the eccentricities of an English winter may be too much for the vitality of such of them as escape their enemies, _Apanteles glomeratus_, and other so-called "ichneumons," and reach the chrysalis state. So, with immigration on the one hand and destructive agencies on the other, it may be understood how it comes about that the Large White is sometimes abundant and sometimes scarce.

This species seems to range over the whole of the British Islands, with the exception, perhaps, of the Shetlands. Abroad, it has been found in all parts of the Palæarctic Region, except the extreme north, and Eastern Asia.

The Small White (_Pieris rapæ_).

The Small White butterfly (Plate 11) is, perhaps, more often in evidence then its larger kinsman just referred to. It also is a migrant, and although it never seems to be absent from these islands, in its proper season, its great increase in numbers in some years is almost certainly due to the arrival of immigrants.

The spring form of this butterfly, named _metra_ by Stephens, who, together with others, considered it a good species, has the tips of the fore wings only slightly clouded with black; and the black spots near the centre of the wings are always more or less faint in the male. Sometimes the central spot and also the blackish clouding of the tip are entirely absent. The summer brood, on the other hand, has fairly blackish tips and distinct black spots--one in the male and three in the female, the lower one lying on the inner margin. Occasionally examples of this flight bear a strong resemblance to the Green-veined White, the next species. The wings are sometimes, chiefly in Ireland, of a creamy colour, more especially in the female, or, more rarely, of a yellowish tint. In North America, where this species was accidentally or intentionally introduced some years ago, bright yellow forms are not uncommon in some localities, and the variety is there known as _novangliæ_.

In certain favourable years a partial third brood has occurred, but such specimens are often small in size.

The egg (Plate 8) is at first pale greenish, but later on it turns yellowish, and this tint it retains until just before the caterpillar hatches out.

The caterpillar when full-grown has a brownish head and a green body; the latter is sprinkled with black and clothed with short blackish hairs emitted from pale warts. There is a yellowish line on the back, and a line formed of yellow spots on the side. It feeds on most plants of the cabbage tribe, and in flower gardens on mignonette and nasturtiums. It is often attacked by parasites, and especially by the _Apanteles_, referred to as destructive to caterpillars of the Large White.

The chrysalis may be of various tints, ranging from pale brown, through grey to greenish; the markings are black, but these are sometimes only faint. It is to be found in similar situations to those chosen by the caterpillar of the last species, but often under the lower rail of a fence or board of a wooden building. Where caterpillars have been feeding in a garden, they often enter greenhouses, among other places, to pupate; and where these structures are heated during the winter, the butterflies sometimes emerge quite early in the year. Distributed throughout the British Islands, except the Hebrides and Shetlands. It is common over the whole of Europe, and extends through Asia to China and Japan. In America, where it was introduced into the United States some forty-five years ago, it has now spread northwards into Canada, and also southwards.

The Green-veined White (_Pieris napi_).

This butterfly is not often seen away from its favourite haunts in the country; these are woods, especially the sunny sides, leafy lanes, and even marsh land. As in the case of the two Whites previously noticed, there are always two broods in the year. The first flight of the butterflies is in May and June, occasionally as early as April in a forward season. These specimens have the veins tinged with grey and rather distinct, but are not so strongly marked with black as those belonging to the second flight, which occurs in late July and throughout August. This seasonal variation, as it is called, is also most clearly exhibited on the under side. In the May and June butterfly (Plate 13, left side) the veins below are greenish-grey, and those of the hind wings are broadly bordered also with this colour. In the bulk of the July and August specimens (Plate 13, right side) only the nervures are shaded with greenish-grey, and the nervules are only faintly, or not at all, marked with this colour.

=Small White Butterfly.=

_Eggs, natural size and enlarged; caterpillar and chrysalids._]

=Large White Butterfly (Summer Brood).=

1, 2 _male_; 3, 4 _female_.]

Now and then a specimen of the first brood may assume the characters properly belonging to the specimens of the second brood; and, on the other hand, a butterfly of the second brood may closely resemble one of the first brood. As a rule, however, the seasonal differences referred to are fairly constant. By rearing this species from the egg it has been ascertained that part (sometimes the smaller) of a brood from eggs laid in June attains the butterfly stage the same year, and the other part remains in the chrysalis until the following spring, the butterflies in each set being of the form proper to the time of emergence.

The strongly-marked specimens (Plate 14) 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 from _P. napi_, L. Stephens ("Brit. Entom. Haust.," I. Pl. iii., Figs. 3, 4) figured a male and a female as _sabellicæ_, which he states differs from _napi_ in 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. 4 of 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. 3 represents a male which certainly seems to be referable to the spring form. Most authors give _sabellicæ_ as belonging to the summer flight, but this does not seem to be correct.

Var. _napææ_ is 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. _bryoniæ_ is 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 Plate 10.

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 a brood 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.

=Green-veined White Butterfly.=

_Eggs, natural size and enlarged; caterpillar and chrysalis._]

=Small White Butterfly.=

1, 2, 4 _male (spring)_, 3 _do. (summer)_; 5, 7, 8 _female (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 form _orientis_, 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 (_Pieris daplidice_).

The Bath White (Plate 14) 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 emerged in the following June. The figures of caterpillar and chrysalis on Plate 12 are from Buckler's "Larvæ."

=Bath White Butterfly.=

_Caterpillar and chrysalis (after Buckler)._]

=Green-veined White Butterfly.=

1, 2 _male (spring)_, 5, 6, _do. (summer)_; 3, 4 _female (spring)_, 7, 8 _do. (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.

The Orange-tip (_Euchloë cardamines_).

This butterfly (Plate 17), 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 the wings. 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 name _hesperidis_ has 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 (Plate 15), 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 the caterpillar 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).

=Green-veined White (Irish).=

1 _male_; 2, 3 _female_.

=Bath White.=

4, 5 _male_; 6 _female_.]

=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 (Plate 15), 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 for some 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 Wood White (_Leucophasia sinapis_).

The graceful little butterfly figured on Plate 19 is 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, Plate 16). Series of each brood are shown on Plate 16, 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 to _Leptosia_, Hüb.

The egg, which is figured on Plate 18, 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.

=Wood White Butterfly.=]

=Orange-tip Butterfly.=

1, 5 _male_; 2 _do. (Irish)_; 3, 6 _female_; 4 _do. (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 and west, 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.

The Pale Clouded Yellow (_Colias hyale_).

This usually scarce butterfly (Plate 21) 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 is pale, 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.

=Wood White Butterfly.=

_Eggs, natural size and enlarged; caterpillar (after Buckler)
and chrysalis._]

=Wood White Butterfly.=

1, 4, 6 _male_; 3 _do. (var.)_; 2, 5, 7 _female_.]

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 Plate 20 is 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 again occur 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.

=Pale Clouded Yellow Caterpillar.=

(_After Hübner._)]

=Pale Clouded Yellow.=

1, 2 _male_; 3, 4 _female_.]

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.

The Clouded Yellow (_Colias edusa_).

In its typical colouring--orange with broad black borders--this butterfly (Plate 22) 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. The female usually has the black borders spotted with yellow, but in some examples these spots are almost (Plate 24, Fig. 1) or quite absent. Another form of the female, known as var. _helice_ (Plate 24, 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 female _helice_. One of these intergrades will be seen on Plate 24, 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 (Plate 23) 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 called _Eurymus hyale_, Linn., and the Pale Clouded Yellow be known as _Eurymus kirbyi_, Lewis.

The Brimstone (_Gonepteryx rhamni_).

This butterfly (Plate 26) 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 (Plate 25). 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 black specks. 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.

=Clouded Yellow.=

1, 3 _male_; 2, 4 _female_.]

=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.