British Butterfiles Part 1

British b.u.t.terflies.

by W. S. Coleman.

PREFACE.

A desire to extend the knowledge of, and by so doing to extend the love for, those sunny creatures called b.u.t.terflies, has prompted the author to undertake this little work, which, though making no pretence to a technically scientific character, will, it is hoped, be found sufficiently complete and accurate to supply all information needful to the young entomologist as to the names, appearance, habits, localities, &c. of _all our British b.u.t.terflies_, together with a general history of b.u.t.terfly life--the mode of capture, preservation, and arrangement in cabinets--the apparatus required, &c. At the same time it is so inexpensive as to be accessible to every schoolboy.

The subject is one which has formed the delight and study of the author from early boyhood, and b.u.t.terfly-hunting still preserves its fascinations, redoubling the pleasure of the country ramble in summer. {vi}

Should this volume be the means of inciting some to seek this source of healthful enjoyment, and to join in the peaceful study which may be so easily pursued by all dwellers in the country, it will have succeeded in its purpose.

The whole of the ill.u.s.trative portraits of the _b.u.t.terflies_ have been drawn from nature by the author, and with one exception from specimens in his own collection. At least one figure of each species (of the natural size) is given; but in very many instances, where the s.e.xes differ considerably from each other, both are figured, and the under sides are also frequently added.

The greater number of the _caterpillars_ and _chrysalides_, however, being rarely met with, the figures on the first plate are nearly all borrowed from the splendid and accurate works of Continental authors--chiefly from Hubner and Duponchel.

With great pleasure, the author here acknowledges his obligations, for many biographical facts relating to b.u.t.terflies, to those highly useful periodicals, the _Zoologist_ and the _Entomologist's Weekly Intelligencer_, the former devoted to general natural history, the latter especially to entomology, and whose pages register a {vii} ma.s.s of interesting and original communications from correspondents who, living in wide-spread localities, and possessing varied opportunities of observation, have gradually brought together, under able editors.h.i.+p, a store of facts that could never have come within the _personal_ experience of any one man, however industrious and observant.

The capture during the past year of a new and interesting b.u.t.terfly for the first time in this country, is recorded in this volume, in which the insect is also figured and described.

BAYSWATER, _April 1860_.

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BRITISH b.u.t.tERFLIES.

CHAPTER I.

INTRODUCTION.

WHAT IS A b.u.t.tERFLY--b.u.t.tERFLIES AND MOTHS--b.u.t.tERFLY LIFE--THE EGG STAGE--SCULPTURED CRADLES--b.u.t.tERFLY BOTANY--THE CATERPILLAR STAGE--FEEDING UP--COAT CHANGING--FORMS OF CATERPILLARS--THE CHRYSALIS--MEANING OF PUPA, CHRYSALIS, AND AURELIA--FORMS OF CHRYSALIDES--DIFFICULTIES OF TRANSFORMATION--INFLUENCE OF TEMPERATURE.

Occasionally a missive arrives from some benevolent friend, announcing the capture of a "splendid b.u.t.terfly," which, imprisoned under a tumbler, awaits one's acceptance as an addition to the cabinet. However, on going to claim the proffered prize, the expected "_b.u.t.terfly_" turns out to be some bright-coloured _moth_ (a Tiger moth being the favourite victim of the misnomer), and one's entomological propriety suffers a shock; not so much feeling the loss of the specimen, as concern for the benighted state of an otherwise intelligent friend's mind with regard to insect nomenclature. {2}

It is clearly therefore _not_ so superfluous as it might at first otherwise seem, to commence the subject by defining even such a familiar object as a _b.u.t.terfly_, and more especially distinguis.h.i.+ng it with certainty from a _moth_, the only other creature with which it can well be confounded.

The usual notion of a b.u.t.terfly is of a gay fluttering thing, whose broad painted wings are covered with a mealy stuff that comes off with handling.

This is all very well for a general idea, but the characters that form it are common to some other insects besides b.u.t.terflies. Moths and hawk-moths have mealy wings, and are often gaily coloured too; whilst, on the other hand, some b.u.t.terflies are as dusky and plain as possible. Thus the crimson-winged Tiger, and Cinnabar _moths_ get the name of _b.u.t.terflies_, and the Meadow brown _b.u.t.terfly_ is as sure to be called a _moth_. So, as neither colouring nor mealy wings furnish us with the required definition, we must find some concise combination of characters that _will_ answer the purpose. _b.u.t.terflies, then, are insects with mealy wings, and whose horns (called "antennae") have a clubbed or thickened tip, giving them more or less resemblance to a drum-stick._ So the difference in the shape of the _antennae_ is the _chief_ outward mark of distinction between b.u.t.terflies and moths, the latter having _antennae_ of various shapes, threadlike or featherlike, but _never clubbed at the tip_.

Having thus settled how a b.u.t.terfly is to be recognized at sight, let us see what b.u.t.terfly _life_ is: how the creature lives, and has lived, in the stages preceding its present airy form.

[Ill.u.s.tration: I.]

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In like manner with other insects, all b.u.t.terflies commence their existence enclosed in minute _eggs_; and these eggs, as if shadowing forth the beauty yet undeveloped whose germ they contain, are themselves such curiously beautiful objects, that they must not be pa.s.sed over without admiring notice. It seems, indeed, as if nature determined that the ornamental character of the b.u.t.terfly should commence with its earliest stage; form, and not colour, being employed in its decoration, sculpture being here made the forerunner of painting.

Some of these forms are roughly shown on Plate II. (figs. 1-7), but highly magnified; for as these eggs are really very tiny structures, such as would fall easily through a pin-hole, the aid of a microscope is of course necessary to render visible the delicate sculpture that adorns their surface. The egg (fig. 1, Plate II.) of the common Garden white b.u.t.terfly (_Pieris Bra.s.sicae_) is among the most graceful and interesting of these forms, and also the most easily obtained. It reminds us of some antique vessel, ribbed and fluted with consummate elegance and regularity.

Others--such as those of the Large Heath b.u.t.terfly (fig. 3), and the Queen of Spain Fritillary (fig. 2), simulate curious wicker-work baskets. The Peac.o.c.k b.u.t.terfly has an egg like a polygonal jar (fig. 4), while that of its near ally, the large Tortoise-sh.e.l.l (fig. 5), is simply pear-shaped, with the surface unsculptured and smooth {4} (fig. 5). The eggs of the Meadow Brown (fig. 6), and the Wood Argus (fig. 7), are globular--the former with lines on its surface like the meridian lines on a geographical globe, and a pretty scalloping at the top that gives a flower-like appearance to that portion; the latter has the whole surface honey-combed with a network of hexagonal cells. Such are a few of the devices that ornament the earliest cradle of the b.u.t.terfly; but probably those of every species would well repay their examination to any one who possesses a microscope.

Prompted by a most remarkable instinct, and one that could not have originated in any experience of personal advantage, the female b.u.t.terfly, when seeking a depository for her eggs, selects with unerring certainty the very plant which, of all others, is best fitted for the support of her offspring, who, when hatched, find themselves surrounded with an abundant store of their proper food.

Many a young botanist would be puzzled at first sight to tell a sloe-bush from a buckthorn-bush. Not so, however, with our Brimstone b.u.t.terfly: pa.s.sing by all the juicy hedge-plants, which look quite as suitable, one would think, she, with botanical ac.u.men, fixes upon the buckthorn; either the common one, or, if that is not at hand, upon another species of rhamnus--the berry-bearing alder--which, though a very different looking plant, is of the same genus, and shares the same properties. She evidently works out the natural system of botany, and might have been a pupil of Jussieu, had she not been tutored by a far higher AUTHORITY.

[Ill.u.s.tration: II.]

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This display of instinct would seem far less wonderful did the mother b.u.t.terfly herself feed on the plant she commits her eggs to. In that case, her choice might have appeared as the result of personal experience of some peculiar benefit or pleasure derived from the plant, and then this sentiment might have become hereditary; just as, for example, the acquired taste for game is hereditary with sporting dogs. Whereas the fact is, that a b.u.t.terfly only occasionally, and as a matter of accident rather than rule, derives her own nectareous food from the flowers of the plant, whose leaves nourish her caterpillar progeny. So that this, as well as numberless other phenomena of instinct, remains a mystery to be admired, but not explained by any ordinary rule of cause and effect.

Having thus efficiently provided, as far as board and lodging are concerned, for the welfare of the future brood, the mother seems to consider them settled for life, takes no further care of them, nor even awaits the opening of the sculptured caskets that contain their tiny life-germs; but, trusting them to the sun's warmth for their hatching, and then to their own hungry little instincts to teach them good use of the food placed within their reach, she sees them no more.

But though abandoning her offspring to fate in this manner, it must not be imagined that the b.u.t.terfly mother takes her pattern of maternity from certain {6} human mothers, and in a round of "b.u.t.terfly's b.a.l.l.s," and such like dissipations, forgets the sacred claims of the nursery. No, she has far other and better excuses for absenting herself from her family; one of which is, that she usually dies before the latter are hatched; and if that is not enough, that the young can get on quite as well without her; for probably she could not teach them much about caterpillar economics, unless, indeed, she remembered her own infantile habits of lang syne, so totally different from those of her perfected b.u.t.terfly life.

The s.p.a.ce of time pa.s.sed in the egg state varies much according to the temperature--from a few days when laid in genial summer weather, to several months in the case of those laid in the autumn, and which remain quiescent during the winter, to hatch out in the spring.

The eggs of b.u.t.terflies, in common with those of insects in general, are capable of resisting not only vicissitudes, but extremes of temperature that would be surely destructive of life in most other forms. The severest cold of an English winter will not kill the tender b.u.t.terfly eggs, whose small internal spark of vitality is enough to keep them from freezing under a much greater degree of cold than they are ever subjected to in a state of nature. For example, they have been placed in an artificial freezing mixture, which brought down the thermometer to 22 below zero--a deadly chill--and yet they survived with apparent {7} impunity, and afterwards lived to hatch duly. Then as to their heat-resisting powers, some tropical insects habitually lay their eggs in sandy, sun-scorched places, where the hand cannot endure to remain a few moments; the heat rising daily to somewhere about 190 of the thermometer--and we know what a roasting one gets at 90 or so. Yet they thrive through all this.

For a short time previous to hatching, the form and colour of the caterpillar is faintly discoverable through the semi-transparent egg-sh.e.l.l.

The juvenile CATERPILLAR, or LARVA, gnaws his way through the sh.e.l.l into the world, and makes his appearance in the shape of a slender worm, exceedingly minute of course, and bearing few of the distinctive marks of his species, either as to shape or colouring. On finding himself at liberty, in the midst of plentiful good cheer, he at once falls vigorously to work at the great business of his life--_eating_; often making his first meal--oddly enough--off the egg-sh.e.l.l, lately his cradle. This singular relish, or digestive pill, swallowed, he addresses himself to the food that is to form the staple fare during the whole of his caterpillar existence--viz. the leaves of his food-plant, which at the same time is his home-plant too.

At this stage his growth is marvellously rapid, and few creatures can equal him in the capacity for doubling his weight--not even the starved lodging-house "slavey," when she gets to her new place, with _carte blanche_ allowance and the key of the pantry; for, in the course {8} of twenty-four hours, he will have consumed more than twice his own weight of food: and with such persevering avidity does he ply his pleasant task, that, as it is stated, a caterpillar in the course of one month has increased nearly ten thousand times his original weight on leaving the egg; and, to furnish this increase of substance, has consumed the prodigious quant.i.ty of forty thousand times his weight of food--truly, a ruinous rate of living, only that green leaves are so cheap.

But the life of a caterpillar, after all, is not merely the smooth continual feast he would doubtless prefer it to be; it is interrupted, several times in its course, by the necessity nature has imposed upon him of now and then changing his coat--to him a very troublesome, if not a painful affair.

For some time previous to this phenomenon, even eating is nearly or quite suspended,--the caterpillar becomes sluggish and shy, creeping away into some more secluded spot, and there remaining till his time of trouble is over. Various twitchings and contortions of the body now testify to the _mal-aise_ of the creature in his old coat, which, though formed of a material capable of a moderate amount of stretching, soon becomes outgrown, and most uncomfortably tight-fitting, with such a quick-growing person inside it: so off it must come, but it being unprovided with b.u.t.tons, there's the rub. However, with a great deal of fidgeting and shoulder-shrugging, he manages to tear his coat down the back, and lastly, by patient efforts, shuffles off the old rag; {9} when, lo! underneath is a l.u.s.trous new garment, somewhat similar, but not exactly a copy of the last, for our beau has his peculiar dress for each epoch of his life,--the most splendid being often reserved for the last.

This change of dress ("_moulting_," it is sometimes called) is repeated thrice at least in the creature's life, but more generally five or six times. Not only does the outer husk come off at these times, but, wonderful to relate! the lining membrane of all the digestive pa.s.sages, and of the larger breathing tubes, is cast off and renewed also.

After each moult, the caterpillar makes up for his loss of time by eating more voraciously even than before, in many instances breaking his fast by making a meal of his "old clo'"--an odd taste, first evinced, as we have seen, in earliest infancy, when he swallowed his cradle.

On Plate I. are shown the chief varieties of form taken by the caterpillars of our British b.u.t.terflies, and a glance at these will give, better than verbal descriptions, a general idea of their characteristics.

Their most usual shape is elongated and almost cylindrical, or slightly tapering at one or both ends. Of these, some are smooth, or only studded with short down or hairs; such are the caterpillars of the Swallow-tail b.u.t.terfly (fig. 1), of the Brimstone (fig. 2), Clouded Yellows, and Garden, and other white b.u.t.terflies. Others, of the same _general_ form, are beset with long branched spines, making perfect _chevaux-de-frise_; such {10} are those of the Peac.o.c.k, Red Admiral, Painted Lady, and the Silvery Fritillaries.

The caterpillars of another large section have the body considerably thicker in the middle (rolling-pin shaped), and the tail part two-forked, or _bifurcate_. This form belongs to the numerous family that includes the Meadow-brown (fig. 3), the Ringlets, and many others.

The _bizarre_ personage, at fig. 4, turns to the graceful White Admiral b.u.t.terfly.

The Purple Emperor begins his royal career in the curious form shown at fig. 5--a shape unique among British b.u.t.terflies, as beseems that of their sovereign; and he carries a coronet on his brow already.

All those beautiful little b.u.t.terflies called the Hair-streaks (fig. 9), the Blues (fig. 10), and the Coppers, have very short and fat caterpillars, that remind one forcibly of wood-lice--a shape shared also by that small b.u.t.terfly with a big name, the Duke of Burgundy Fritillary (fig. 8), an insect very distinct from the Fritillaries above mentioned with th.o.r.n.y caterpillars.

The _legs of a caterpillar are usually sixteen in number_, and composed of two distinct kinds, viz. of _six true legs_, answering to those of the perfect insect, and placed on the foremost segments of the body; and of _ten_ others, called "_prolegs_;" temporary legs, used princ.i.p.ally for strengthening the creature's hold upon leaf or branch.