LITTLE BLUE BOOK NO. =796= Edited by E. Haldeman-Julius Life Among the Butterflies Vance Randolph, B. Sc., A.M. Drawings by Peter Quinn HALDEMAN-JULIUS COMPANY GIRARD, KANSAS Copyright, 1925, Haldeman-Julius Company. PRINTED IN THE UNITED STATES OF AMERICA LIFE AMONG THE BUTTERFLIES CONTENTS Chapter I. Books About Butterflies 7 Linnaeus--Clerck--Fabricius--Peter Cramer--Hübner--Smith and Abbot--Boisduval and LeConte--Harris--Morris--W. H. Edwards--S. H. Scudder--G. H. French--C. J. Maynard--W. J. Holland--William G. Wright--Longstaff--C. M. Weed. Chapter II. The Butterfly’s Body 12 The Head, Eyes, and Mouth Parts--The Thorax, Wings, and Legs--The Abdomen--The Digestive Apparatus--The Circulatory System--The Respiratory Tract--The Excretory Organs--The Nervous System--The Reproductive Organs. Chapter III. Butterfly Metamorphosis 19 The First Stage or Egg--The Second or Larval Stage--The Third or Pupal Stage--The Fourth Stage or Imago. Chapter IV. The Case of the Red Silverwing 23 Oviposition--The Egg--The Emergence of the Caterpillar--The Caterpillar--Moulting--Pupation--The Chrysalis--Pupal Movements--The Appearance of the Butterfly. Chapter V. The Classification of Butterflies 33 Subkingdoms, Classes, Orders and Suborders--The Four Families--Subfamilies, Genera, and Species--The Value of Scientific Nomenclature--Varieties. Chapter VI. The Four Families 38 The Four-footed Butterflies--The Euploeinae--The Heliconiinae--The Nymphalinae--The Satyrinae--The Libytheinae--The Gossamer-winged Butterflies--The Lycaeninae--The Swallowtails and their Allies--The Pierinae--The Papilioninae--The Skippers. Chapter VII. Enemies and Protection 55 Protective Coloration--Offensive Odors and Tastes--Warning Coloration--Protective Mimicry--Heliotropism and List--Feigning Death. LIFE AMONG THE BUTTERFLIES CHAPTER I BOOKS ABOUT BUTTERFLIES Many ancient and mediaeval writers dealt with butterflies, but the first descriptions of American species are found in the works of Linnaeus, the great Swedish naturalist who wrote about 1750, and invented the system upon which all modern classification is based. Pictures of several American butterflies were published in 1759 by Charles Clerck, who had studied with Linnaeus. Johann Christian Fabricius, a professor at the University of Kiel, published a few more descriptions in 1796, and Peter Cramer, at about the same time, brought out four large volumes on the butterflies of Asia, Africa, and the Americas. Most of these early books were written in Latin, and are now so rare and expensive that few American students have ever seen them. Jacob Hübner published his great volumes on exotic butterflies in the early part of the nineteenth century. This work was written in German, and contained more than six hundred colored plates, but a good copy now costs about eight hundred dollars, and is of very little use anyway. In 1797 Sir James Edward Smith brought out his two-volume work on _The Natural History of the Rarer Lepiodopterous Insects of Georgia_, the first books ever devoted exclusively to North American species. This work is valuable chiefly because it contains some drawings by John Abbot, an Englishman who had actually lived in Georgia and studied moths and butterflies at first hand. Some of Abbot’s pictures were later used in another work on American lepidoptera by Dr. J. A. Boisduval of Paris, and Major J. L. LeConte of New York, who wrote in French about 1833. The books of both Smith and Boisduval are now practically unobtainable. In 1841 the Biological Survey Commission of Massachusetts published a report on injurious insects by Dr. Thaddeus William Harris, which described many New England butterflies. It is now out of print, the last edition appearing in 1862. The Rev. John G. Harris brought together a deal of information from the works of other writers, and made a few minor observations of his own; his compilation was published by the Smithsonian Institution about 1860. In 1868 William H. Edwards, an engineer who lived in Coalburg, West Virginia, brought out the first volume of his famous work, _The Butterflies of North America_--probably the best book on the subject ever written. Edwards laboriously worked out the life-histories of many species, and illustrated the work by careful drawings and paintings of his own. Two more volumes appeared later, the last one published in 1897. _The Butterflies of North America_ is a magnificent piece of work, produced under all sorts of handicaps, and will always be a classic to American students of the subject. In 1886 Dr. Samuel Hubbard Scudder published his _Butterflies of New England_ in three volumes; this monograph is superbly illustrated, and compares very favorably even with the epoch-making work of Edwards. The works of Edwards and Scudder are probably the best books on butterflies ever written in any language, and must always remain as monuments of American industry and scholarship. Because of the excessive cost of reproducing the colored plates, however, they are both rather expensive; Scudder’s work retailed at ninety dollars, while Edward’s three volumes never sold for less than a hundred and fifty, and even this price, according to Dr. W. J. Holland, was below the cost of manufacture. _The Butterflies of the Eastern United States_, by G. H. French, appeared about 1886. It is a good little book, and is still in common use, but the illustrations are few and unsatisfactory. In 1891 C. J. Maynard published a _Manual of North American Butterflies_ with ten colored plates; the plates are very poor indeed, and the text not much better. In 1893 Dr. Samuel Hubbard Scudder, the author of the three great volumes on the New England species, brought out a little book called _The Life of a Butterfly_. It is a brief and popular account of the life-history of _Anosia plexippus_, the Monarch or Milkweed butterfly, which is common everywhere. Dr. Scudder’s _Brief Guide to the Commoner Butterflies of the Northern United States and Canada_ also appeared in 1893--a very useful little book. In 1898 Dr. W. J. Holland, Director of the Carnegie Museum at Pittsburgh, published his famous _Butterfly Book_, in which he described more than five hundred species, accompanying each description with a sketch of the life-history and habits in all cases where these details were known. The magnificent colored photograph plates are quite equal for all practical purposes to the hand-colored drawings of Edwards and Scudder, and enable the veriest tyro to classify any of the commoner butterflies simply by comparing them with the pictures. Besides the detailed description of each species there is a great deal of miscellaneous information of interest to the general reader. Because of the new process of reproducing photographs in colors the book sold very cheaply--never more than four or five dollars--and has done more to arouse a popular interest in butterflies than all other works together. Many of the elementary books since 1898 are indebted to Holland’s book, and the present booklet is no exception. In 1905 William Greenwood Wright of San Francisco, published a book called _West Coast Butterflies_. This work is illustrated with colored plates nearly as good as Holland’s, and is indispensable to those interested in California species. George B. Longstaff’s _Butterfly-Hunting in Many Lands_ appeared in 1912. The book itself is of no great interest to North Americans, as Longstaff spent only two weeks here, and came no farther south than Montreal. Still, his chapter of _Bionomic Notes_ deals with butterflies in general and is well worth reading. The best part of the book, however, is the appendix, which contains E. A. Elliott’s translations of Fritz Müller’s famous papers on scent-producing organs in butterflies. The most important of these had never been published except in some obscure Portuguese journals, practically inaccessible to the American student. In 1916, encouraged by the success of his _Butterfly Book_, Dr. Holland prepared a pocket manual called the _Butterfly Guide_, with colored figures representing some two hundred and fifty species. In 1917 there appeared Clarence M. Weed’s _Butterflies Worth Knowing_, with thirty-two plates in color. This is one of the best of the smaller popular books, and contains a great deal of valuable modern material, but is not to be compared with Holland’s work. No important popular books on butterflies have appeared in recent years. The best single work for the general reader is still Holland’s _Butterfly Book_; those living west of the Rockies should have Wright’s _West Coast Butterflies_ also. CHAPTER II THE BUTTERFLY’S BODY The body of a butterfly, like that of any other insect, is divided by constrictions into three parts: the head, the thorax, and the abdomen. The head carries the eyes, antennae, and mouth parts; the thorax bears the legs and wings; and the abdomen the sexual appendages. THE HEAD, EYES, AND MOUTH PARTS The _head_ is globular, usually a little flattened from front to rear. Two large _compound eyes_ are located at the sides of the head, and the face or front consists largely of a plate called the _clypeus_. Above the clypeus and between the eyes are the _antennae_ or feelers, which are believed to be the organs of hearing, smell, and touch. Below the clypeus is the _labrum_ or upper lip, and the rudimentary _mandibles_; just below these are the two _maxillae_, which unite to form a tube called the _proboscis_, used in sucking nectar out of flowers. When not in use the proboscis is coiled up like a watch-spring between the two three-jointed _labial palpi_. The _labium_ or lower lip is very small in butterflies. THE THORAX, WINGS AND LEGS The _thorax_ is composed of three segments, the front part or prothorax, the middle part or mesothorax, and the hind part or metathorax. The _prothorax_ bears the front legs; the _mesothorax_ the second pair of legs and the fore wings; the _metathorax_ carries the third pair of legs and the hind wings. The under side of the thorax is called the _pectus_ or breast. The large muscles which operate the legs and wings are contained in the thorax. One pair of _spiracles_ or breathing-holes is found in the prothorax; the other seven pairs are located in the abdominal segments. The butterfly has four _wings_, which are the largest and most conspicuous part of the insect. The wings consist of membranes stretched over horny tubes called veins; in the newly emerged insect the veins contain both blood and air, but the veins of the adult contain air only. The colors of the wing are due to minute _scales_ which cover the membranes in an overlapping fashion like shingles on a roof. The scales vary considerably in size and form as well as in color, and the males of some species bear specialized scales known as _androconia_, which produce odors attractive to the females. The third of the wing nearest the body is the _base_; the middle part of the wing is the _median_ or _discal_ area; the outer portion is called the _limbal_ area. The front edge is the _costal margin_; the outer edge is the _external margin_; the posterior edge is known as the _inner margin_. The angle of the outer and inner margins of the front wings is called the outer angle, and the corresponding angle of the hind wings is the inner or anal angle. The outmost tip of the front wing is called the _apex_. The fore wing has three simple veins: the _costal_, the _radial_, and the _submedian_. There are also two branching veins, the _median_ and the _subcostal_. The median vein has three branches or nervules, while the subcostal usually has four or five. The hind wing has five simple veins: the _costal_, _subcostal_, _upper radial_, _lower radial_, _submedian_, and _internal_. The costal vein in the hind wing usually has a short ascending spur called the _precostal_ vein but it is classed as a simple vein none the less. The median vein has three nervules, as in the fore wing. In both fore and hind wings, between the subcostal and median veins, there is an area called the _cell_, which is often closed or partially closed on the outer side by three _discocellular veins_, designated as upper, middle, and lower. Each of the six _legs_ is divided into five parts. The section nearest the body is the _coxa_, which is attached to the ring-like _trachanter_. Next beyond the trachanter is the _femur_, then the _tibia_, and finally the _tarsus_ or foot bearing the tarsal claws, which are used in clinging to various objects when the butterfly is at rest. In some species the fore legs are small and quite useless, a fact which is used in classification. THE ABDOMEN The _abdomen_ is composed of ten segments; the first seven bear _spiracles_ or breathing-holes (completely hidden by scales, however) and the last two segments are modified to form external sexual appendages. In the male there is a pair of _claspers_ for holding the female during copulation; in the female there is only a short and simple _ovipositor_. THE DIGESTIVE APPARATUS The _alimentary canal_, the principal part of the digestive apparatus, is a tube extending through the entire body from the end of the proboscis to the anal opening. Just above the proboscis is a _bulb_, which is enlarged by the contraction of muscles attached to the hard parts of the head. When the bulb is expanded nectar may be sucked up through the proboscis; then the valve at the end of the proboscis is closed, and the bulb contracted again. By this means the liquid is forced back into the _esophagus_ or gullet, and hence into the _crop_. Just behind the crop is the _stomach_, and just behind the stomach is the _small intestine_. From the small intestine the part of the liquid not absorbed flows into the _large intestine_, which is divided into a front part or _colon_, and a rear and lower part called the _rectum_. From the rectum the fecal matter passes out of the body through the _anal opening_. THE CIRCULATORY SYSTEM The _circulatory system_ consists essentially of a single blood vessel, running the entire length of the body in about the position occupied by the spinal column in the higher animals. This tube is open at the rear, and has valves opening inward all along its sides. In the thorax there is a pulsating enlargement which serves as a simple _heart_. The _blood_ is a colorless liquid which percolates about through the entire body cavity, not being confined to any particular arteries or veins. It is ultimately collected into the dorsal blood vessel, and the pulsating heart keeps it moving, so that it absorbs food from the stomach and intestines, and distributes it to the various parts of the body. [Illustration: Fig. I.--Diagram showing internal structure. 1, proboscis; 2, bulb; 3, brain; 4, heart; 5, crop; 6, dorsal blood vessel; 7, small intestine; 8, colon; 9, rectum; 10, anal opening; 11, Malpighian tubule; 12, stomach; 13, ventral nerve cord; 14, esophagus; 15, subesophageal ganglion.] THE RESPIRATORY TRACT Insects have no lungs, and the blood does not carry oxygen about as in the higher animals; air is drawn into the body and brought into direct and immediate contact with the tissues. In the butterfly there are eight pairs of _spiracles_ or breathing-holes--seven pairs in the abdomen and one in the prothorax. These spiracles are connected with large _air-sacs_ reaching from one end of the body to the other, each air-sac being provided with minute branching tubes called _tracheae_, which carry air directly to the various tissues of the body. The carbon dioxide produced in the respiratory changes passes out through the spiracles, the transfer of gases being produced largely by movements of the abdominal muscles. THE EXCRETORY ORGANS The abdomen of the butterfly contains a number of slender _Malpighian tubules_, in contact with the blood contained in the various cavities. These tubules extract waste matter from the blood, functioning just as kidneys do in the higher animals. The butterfly has no bladder or urethra, however; the Malpighian tubules empty into the small intestine, and the urine passes out of the body with the fecal matter. THE NERVOUS SYSTEM The nervous system consists of the brain, the subesophageal ganglion, and the ventral nerve cord, together with branches of these structures. The _brain_ is a large mass of nerve tissue in the head just above the esophagus. The two _optic nerves_ which supply the large compound eyes make up the principal part of the brain, being much larger and more complicated than the _cerebrum_, which is supposed to be the organ of sensation. The _subesophageal_ ganglion is a sort of second brain lying just below the esophagus; it gives off nerves which supply the mouth parts and control the mechanism of feeding. The _ventral nerve cord_ runs back from the subesophageal ganglion and traverses almost the entire length of the body, being analogous to the spinal cord of the vertebrates. It bears three _ganglia_ in the thoracic region which give off nerves to the legs, wings, and thoracic muscles. Other ganglia, located in the abdomen, have many branching nerves which are distributed to the abdominal muscles and the viscera. THE REPRODUCTIVE ORGANS The _ovaries_ in the female butterfly are sometimes so large as to crowd the other organs in the abdominal cavity. They communicate by means of tubes called _oviducts_ with the _copulatory_ apparatus at the end of the abdomen. The _testes_ of the male butterfly are usually combined into a single organ; they discharge the _seminal fluid_ into the _vas deferens_, whence it is conducted to a sort of pouch near the penultimate segment of the abdomen. In copulation the ends of the male and female abdomens are locked together by certain clasping appendages, and the seminal fluid of the male is forced into the body of the female, where it meets and fertilizes the eggs as they descend from the ovaries. CHAPTER III BUTTERFLY METAMORPHOSIS Some insects, grasshoppers for example, pass through an _incomplete metamorphosis_; that is, the young grasshopper is very much like its parents except as regards size. This is the same sort of development found among birds, reptiles, and other vertebrates. The egg of a butterfly, however, does not hatch into a miniature replica of its parents, but into an altogether different sort of creature, which must pass through a _complete metamorphosis_ before it becomes a butterfly. To put the matter briefly, there are four distinct stages in the life of a butterfly: the egg, the caterpillar, the chrysalis, and the imago, or butterfly proper. THE FIRST STAGE OR EGG Female butterflies are equipped with organs called ovaries which produce ova, and male butterflies have testes which produce sperm. By an act called copulation (in which the male and female abdomens are locked together by appropriate appendages) the sperm of the male is introduced into the body of the female. A single spermatozoon fuses with each ovum, and the result is a fertilized egg. The female deposits the egg upon a green leaf, and as a rule each species is limited to one or two particular kinds of plants. Butterfly eggs are small, but always large enough to be seen with the naked eye, and they vary widely in shape and color as well as in size. THE SECOND OR LARVAL STAGE [Illustration: Fig. II.--The Viceroy (_Basilarchia disippus_), an example of the family Nymphalidae, or four-footed butterflies. This is the butterfly that mimics the Monarch; see section on Protective Mimicry. A, egg; B, caterpillar; C, chrysalis; D, imago.] Most butterfly eggs hatch within a week or two, producing worm-like larvae called _caterpillars_, which differ in appearance according to the species, but whose general characteristics are well known. The principal business of a caterpillar is to eat; no sooner has it emerged from the egg than it devours the egg-shell, and then sets to work on the leaves of the food plant. Its growth is so rapid that the outer skin must soon be shed, and this shedding process is known as moulting. Most caterpillars moult about four times. The caterpillar stage usually lasts only a month or so, but there are a few species which hibernate and spend the winter as caterpillars. THE THIRD OR PUPAL STAGE When the caterpillar is fully grown it spins a little silken button on some solid object, hangs itself up by the tail, and undergoes a final moult. When the old skin peels off this time it reveals, not a caterpillar with a bright new skin, but a different sort of creature altogether. The apparently lifeless pupa or _chrysalis_ shows some of the characteristics of a butterfly, but the wings and legs are folded up, the antennae are cemented fast against the body, and the whole structure covered by a horny, tight-fitting sheath. This state of affairs usually lasts only three or four weeks, but some butterflies, particularly in temperate climates, pass the winter in the pupal state. THE FOURTH STAGE OR IMAGO When the chrysalis stage is over the outer skin bursts open about the head, and the _imago_--the butterfly proper--crawls out. The newly emerged butterfly is a sorry-looking specimen; the wings are very small and flaccid, and it can do no more than cling to some convenient support, usually the empty skin of the chrysalis. After a while, however, the body juices flow out into the wings, which expand and harden, and in a few hours the young butterfly is flitting from flower to flower with its fellows. Ordinarily the imago does not live long--often only a few days. Just as the caterpillar’s sole business is to eat, the mature butterfly has only one important function, and that is reproduction. It speedily finds a mate (that’s what its wings are for), contributes its quota of ova or sperm to produce another generation of caterpillars, and its ephemeral existence as a butterfly is over. CHAPTER IV THE CASE OF THE RED SILVERWING Having dealt briefly with the transformations of butterflies in general, it may be well to examine more closely into those of a single representative species. For this purpose I have chosen _Dione vanillae_, known as the Red Silverwing, and have described each stage and transition in considerable detail. The following paragraphs are extracts from the daily records of a study I made in southern Kansas, the northern limit of _vanillae’s_ usual range. OVIPOSITION “One of the females, alighting upon the upper side of a leaf within ten inches of my face, suddenly elevated the forward part of the body, brought the wings together vertically, curved the abdomen slightly forward, and drew its tip slowly across the surface of the leaf for a distance of approximately 12 mm. Remaining quiet for an instant, it lifted the abdomen, showing an egg firmly attached to the leaf. The eggs are laid singly, usually in the upper middle of the leaf. I have never seen more than one upon the same leaf.” THE EGG “The egg measures about 1.12 mm. in height and .7 mm. in diameter at the widest part, barrel-shaped, with fourteen vertical ribs. A brilliant yellow at first, it assumes after about thirty-six hours a reddish brown color. A few hours later an irregular, whitish broken ring, not quite circling the egg, appears about one-third of the distance from the top. When within an hour or so of hatching the shell becomes very thin and transparent and reflects the light with a sort of frosted-glass effect. The large black head of the larva inside gives the upper one-third of the egg a black, metallic appearance, while the yellowish body may be seen curled up in the lower part. The incubation period seems to vary greatly with the temperature, from forty-seven hours to seven days.” THE EMERGENCE OF THE CATERPILLAR “At 2:15 p. m. the larva was clearly visible through the shell. Slight bodily movements were noted, then the very large, shining black head was thrust out at a point on one side of the egg, just below the top. The entire structure rocked and swayed slowly back and forth, inclining toward the side from which the head projected. “At 2:19 the larva emerged very slowly, head first. The head and the final segment appeared very large. The entire length was about 1.5 mm. The body yellowish red; prolegs and caudal segment lemon yellow; the head, legs and spines black. The latter bear no visible branches, and appear as stiff, black hairs, each growing out of a slight black protuberance. “The beautiful egg-shell remains erect, the form being unchanged. There is a ragged hole in it, but it is scarcely noticeable, and appears hardly large enough for the egress of the caterpillar.” THE CATERPILLAR “The newly emerged larva does not venture far from the egg-shell and does not move about much for the first five or six hours. It sometimes devours the shell, but this is not usually the case. At the age of six hours it appears darker, and the black spots from which the hairlike spines protrude have become more conspicuous. Has not eaten any of the leaf, and has increased in size very little if at all.” “At the age of twenty-seven hours the larva attains a length of 2.3 mm. and has eaten several small holes in the center of a large leaf, gnawing through the leaf to the transparent epidermis on the opposite side, which is left intact. Usually works from the upper side, but by no means invariably.” “These smaller larvae seem to be always attached to the leaf with silk, although the threads are very few and fine. More mature larvae feed differently; they grip the petiole with the prolegs, and eat from the edge inward and forward, swinging the head toward the midrib, with practically no lateral motion.” “The caterpillar is cylindrical and bears six rows of black, branching spines, twelve in each row. As regards color, there are besides the reddish, newly hatched creature described above, two well-defined types: the orange-drab and the drab-orange. In the first the body appears orange with three narrow drab stripes, and a very narrow lateral line just above the prolegs. In the second the drab markings become very much more prominent, so that the body now appears drab with four narrow orange stripes. The narrow drab dorsal line of the younger caterpillar becomes very conspicuous in the mature larva, separating the dorsal surface into two distinct orange areas. As the orange-drab type seems to embrace all of the smaller larvae, and as all those about to pupate belong to the drab-orange type, I have assumed that the color change is a matter of maturity.” MOULTING “1:30 a. m.--Larva about 21 mm., inactive and very dark, extended on lower side of leaf, front of body high, head bent, holding with third, fourth and anal prolegs. A few silk threads lie flat on leaf near caudal end of body. After some little rippling of muscle (no violent motion) the skin of the body separates from that of the head. The former is very tight; slowly, segment by segment, it is skinned backward until finally it is left, a crumpled, prickly black ball about 4 mm. in diameter, fastened to the leaf by the aforementioned silk. Meanwhile the head covering, which is all of a piece and bears two large spines, slips forward until it appears to be held in the mandibles as a hat might be held between the teeth. After a moment it falls to the ground. The caterpillar now appears somewhat short and a trifle thickened. The head, legs and prolegs are yellow, the body orange. The spines are only half size, blunt, yellow and semi-transparent. The branches appear as black hairs lying flat along the sides of the spines.” “11:33 a. m.--The spines have now attained practically their normal size, springing out with astonishing rapidity. They are still blunt, yellow and semi-transparent, but the black branches have reached normal size and assumed their proper position. The two head spines, which were curled backward, have taken on the usual angle. The head, body and prolegs now appear orange rather than yellow, the head being lightest. The drab dorsal stripe has appeared, but is very narrow. The row of depressions, one in the dorsal center of each segment, is much more conspicuous than usual.” “11:50 a. m.--Appears quite normal again, except that the spines are not quite as black, showing grayish toward the tips. The black frontal markings appear. Caterpillar rests motionless.” “12:10 p. m.--Turns about and begins to devour the cast-off skin. With the lens I watched it begin at the tip of one of the big spines and consume it clear to the root, apparently in about three mouthfuls. The head covering is never eaten.” “12:30 p. m.--Skin practically consumed. Larva rests motionless, a few of the surplus spines resting beneath the head and thorax.” PUPATION “10:00 a. m.--Caterpillar, 37 mm. long, leaves food plant and begins to wander restlessly about. “1:00 p. m.--Extended motionless, clinging to under side of window frame. “2:30 p. m.--Same position. “3:30 p. m.--Begins to lay a sparse, ragged network of very fine threads flat to the surface, covering a space of perhaps an inch square. These threads become thinner toward the periphery of the net, where they are hardly visible without a lens. “4:00 p. m.--Spins a little white silk button in the center of the network. The head moves slowly out horizontally in all directions from the button about one-half inch, swinging always back to the center. The body is fully extended, the abdomen being away from the button. “4:30 p. m.--Interrupted the button-making to raise high the caudal third of the body, spreading the anal appendages apart several times. When a pellet of excrement appeared, the caterpillar turned about and pulled it out of the anal opening with the mandibles, holding it thus a moment before allowing it to fall to the floor. “4:45 p. m.--Resting, body extended, clasping the button with the third prolegs. “6:00 p. m.--Fastened to the button. The body is extended horizontally, clinging to the under surface of the window frame with the prolegs; head drawn back, legs not touching the surface. “8:00 p. m.--Hanging from the button. The body is thickened a trifle and shortened to 31 mm. Color much lighter; hangs motionless except for very slight movements of the legs and prolegs.” “9:00 a. m.--No change. “10:00 a. m.--The brilliant colors have practically disappeared, leaving the body a pearl-gray color, against which the black spines show up with startling distinctness. Movements slight and infrequent. The dorsal thorax is now the lightest part of the body. “11:00 a. m.--Begins to wriggle a little. “11:10 a. m.--I note that the spines appear closer together at the caudal end of the body; then see that the skin has split down the back and that the light-colored head of the chrysalis is protruding. By a series of vigorous wrigglings the skin is slowly forced up to where the tip of the abdomen is attached to the button. Then comes the violent struggle which finally loosens the skin, which hangs for a moment against the ventral abdomen, then falls to the floor. The entire moult is complete in less than five minutes.” THE CHRYSALIS “When the chrysalis first appears it is nearly cylindrical; no dorsal depression, no ventral bulge. The head is bent forward, and the whole thing has a compact, slug-like appearance. An hour or so later the head is no longer bent, and bears two double projections, set wide apart; the wing cases are bulging and prominent; on the dorsal side, opposite the middle of the wing covers, is a U-shaped depression; there are projections on the third, fifth, sixth, and seventh abdominal segments, those on the third being the largest. At first the head, thorax and wing covers are translucent and nearly white; the abdomen is a little darker and bears a ventral bluish stripe on the fourth, fifth and sixth segments. The four pairs of dorsal protuberances are amber-colored. “An hour later the head and thorax darken somewhat, and opaque whitish veins appear in the wing covers. Distinct black lines mark the outer borders of the fore wings, and a black V-shaped mark shows the position of the larger of the three discal spots. “Another hour and the translucent appearance is gone, the abdomen and the dorsal thorax become much darker, the wing covers grayish tan, while the bluish ventral stripe turns gray or white. “From this time forward the chrysalis does not change appreciably in form or color (although the latter varies greatly) until about twenty-four hours before the emergence of the butterfly, when the entire body becomes very dark. “The average length of the chrysalis is 28 mm., and the white ventral stripe is usually the most conspicuous marking. After the butterfly has emerged the color variations of the chrysalis still persist in the empty shells, some being much darker than others. “Not infrequently the cast skin of the larva is found attached to the anal portion of the chrysalis. This skin is black excepting the head, which is gray, and the black branching spines loom large because of the contraction of the empty skin. “Sometimes the chrysalids turn bright yellow; these are usually infested by parasites. I have opened many of these pupae, but have never found the parasitic larva itself; the pupae and adults I have often taken, the latter being a small (2.3 mm.), green hymenopterous insect which I have not as yet had the opportunity to classify. Some ten or a dozen of these insects emerge from a small round hole, usually in the wing cover, in early August.” PUPAL MOVEMENTS “The chrysalis seems unable to bend the body toward the back or toward the wing covers; sidewise, however, it can turn until the body is extended nearly parallel to the horizontal surface from which it is suspended. Six chrysalids which hung in a north window in September, 1919, and which I observed for fourteen days, were noted to be invariably and unanimously pointed inward (toward the warm room, that is) every morning. During the warmer part of the day there was no uniformity in position. Six specimens--fourteen days; it appears to be more, perhaps, than mere coincidence. The pupal sensibility to light and temperature stimulii should be worth investigation.” THE APPEARANCE OF THE BUTTERFLY “Two or three weeks after pupation (the period varies with the temperature, from eight days in August to twenty-seven in November) the chrysalis turns nearly black, and a diagonal fissure appears on either side, extending from the back of the head down along the antenna cases, nearly to the middle ventrum. “About twelve hours later, after some little wriggling, the ventral triangle formed by the covering of the head, antennae and mouth parts falls open trap-door fashion, the antennae covers serving as hinges and the flexing point being about one-third of the distance up the wing covers from the abdomen. There is also a dorsal cleavage following the medial dorsum to the first abdominal segment, then the outline of the wing covers to a point half way to the end of the antenna covers. The crumpled-winged imago wriggles out and mounts the empty shell, to which it clings by the four hinder limbs, turning the entire body back and forth as if mounted on a pivot. In each of these turns the body describes an arc of nearly 90 degrees, the body being held stiff. The angle of the body is about 45 degrees from the vertical, the head being uppermost. The proboscis is usually partially unrolled. In five or six hours the soft, wrinkled wings spread and harden, and the insect is able to fly. A thin, transparent liquid, and sometimes a thick, reddish substance, are voided by the newly emerged butterfly.” CHAPTER V THE CLASSIFICATION OF BUTTERFLIES In every science it is necessary to manipulate a large number of related facts, and this cannot be done unless the data are arranged in some systematic and orderly fashion. In order to make use of the facts about butterflies, one must know something of the relation of one butterfly to another, and the relation of butterflies in general to the rest of the animal kingdom. SUBKINGDOMS, CLASSES, ORDERS, AND SUBORDERS Members of the animal kingdom which have no spinal column, but only an external skeleton composed of horny rings, are assigned to the subkingdom _Arthropoda_. Arthropods which have six legs are grouped together in the class _Insecta_. Insects with scales on their wings are assigned to the order called _Lepidoptera_. This order is divided into two suborders, the _Rhopalocera_ or butterflies and the _Heterocera_ or moths. Butterflies fly in the daytime, and have slender antennae with club-like knobs at the ends; moths are usually nocturnal or crepuscular, and their antennae are not knobbed, but are thread-like, feather-like, or hooked at the extremity. THE FOUR FAMILIES The suborder Rhopalocera is divided into four families: the _Nymphalidae_, the _Lycaenidae_, the _Papilionidae_, and the _Hesperiidae_. The _Nymphalidae_ or four-footed butterflies make up the largest family; the first pair of legs are much smaller than the others, and are quite useless for walking. Most of the Nymphalidae are large or medium-sized butterflies. The caterpillars are usually provided with spines or fleshy protuberances, and the chrysalids are always suspended by the tail. The _Lycaenidae_ or gossamer-wings are the bright little butterflies known as “blues,” “hair-streaks,” and “coppers.” The males do not use the first pair of legs in walking, but the females do. The caterpillars are small and usually slug-shaped, and the chrysalids are held closely attached to some object by a girdle of silk. The _Papilionidae_ is the family of the swallowtails and allied forms. Both sexes use all six feet in walking. The butterflies are usually large or medium-sized; many of the caterpillars produce disagreeable odors; the chrysalids are suspended by the tail and provided with a girdle of silk, but not drawn up to the surface to which they are attached, as in the case of the _Lycaenidae_. The _Hesperids_ or skippers are small butterflies with thick, moth-like bodies and a peculiar manner of flight. Both sexes have six walking feet. The caterpillars are smooth and thin-necked, with large globular heads. The chrysalids are usually enclosed in a flimsy cocoon of leaves fastened together with a few silk threads. SUBFAMILIES, GENERA, AND SPECIES Each one of these four families is divided into several subfamilies; each subfamily is divided into several genera, and each genus is divided into several species, all of these divisions being based on an increasing anatomical similarity. Thus the common Milkweed Butterfly belongs to the class _Insecta_, the order _Lepidoptera_, the suborder _Rhopalocera_, the family _Nymphalidae_, the subfamily _Euploeinae_, the genus _Anosia_, and the species _Plexippus_. THE VALUE OF SCIENTIFIC NOMENCLATURE One may well ask why we do not simply say “milkweed butterfly” and have done with it, but this term refers merely to the fact that the caterpillar feeds upon a certain plant, while _Anosia plexippus_ places the specimen definitely in the scientific scheme of things, and designates important structural distinctions which have nothing to do with milkweeds. The average American is prone to call any insect a “bug” or “moth-miller” or some such unenlightening name, so that many butterflies have no common English name at all, while others have many different names which vary widely in different parts of the country. Besides, the Greek and Latin names are understood by scientists in all countries, and are less liable to corruption than terms taken from the modern languages. There are difficulties enough in the scientific nomenclature, without complicating matters by the introduction of popular names. It is a fixed rule in science that the first man to discover and describe a species has the right to name it, and that whatever name he chooses shall be used by everybody forever, but scientists are only human after all, and are always anxious to discover new species and name them after their friends or sweethearts. It often happens that a single species is described independently by several authors, each of which applies a name of his own devising; in this case the first is the real name, and the others are called synonyms. In writing about butterflies it is not customary to spell out the generic name; one does not write _Dione vanillae_, but merely _D. vanillae_. It is usual also to add the name of the man who first named the species, so that the name becomes _D. vanillae_, Linnaeus, or _D. vanillae_, Linn. In conversation one may omit the name of the genus altogether, and refer to the butterfly simply as _Vanillae_. It is well to remember that scientific Latin in this country is pronounced in the insular fashion--that is, the words are pronounced as if they were English. VARIETIES Sometimes the individuals of a species differ in different parts of the country; these different forms are called _varieties_, and are designated by a varietal name added to the generic and specific names. _Papilio turnus_, Linn. is a large yellow swallowtail, but in the southern part of its range some of the females are black. The black female was formerly regarded as a distinct species, and Linnaeus named it _Papilio glaucus_, but when it was reared from eggs laid by a yellow female it was recognized as a variety, and is now known as _Papilio turnus_, Linn., var. _glaucus_. CHAPTER VI THE FOUR FAMILIES As we said in the chapter on Classification, American butterflies fall naturally into four great groups called families: the _Nymphalidae_ or Four-footed family, the _Lycaenidae_ or Gossamer-winged family, the _Papilionidae_ or Swallowtail family, and the _Hesperiidae_ or Skipper family. THE FOUR-FOOTED BUTTERFLIES The largest family of butterflies in America is the _Nymphalidae_, and its members are called four-footed butterflies because the front legs are so small as to be useless, leaving only four walking feet. Most of the butterflies are large or medium-sized, the caterpillars are usually provided with spines or fleshy protuberances, and the chrysalids are always suspended by the tail. The family is divided into five subfamilies; the _Euploeinae_, the _Heliconiinae_, the _Nymphalinae_, the _Satyrinae_, and the _Libytheinae_. THE EUPLOEINAE [Illustration: Fig. III.--The Silver-Spotted Skipper (_Epargyreus tityrus_), a typical Hesperid. A, egg; B, mature caterpillar; C, pupa or chrysalis; D, imago.] So far as the great majority of readers are concerned, this subfamily includes but one species--_Anosia plexippus_, the familiar Monarch or Milkweed butterfly, which is common every summer in every state in the Union. The main color of the wings is bright reddish brown, but the edges are black, and there are some white spots in the black area, particularly in the fore wings. The pale green eggs are laid upon the milkweed, and soon hatch into little black and white caterpillars. The mature caterpillar is greenish yellow with black bands, and each end of the body bears a pair of slender black “horns” or _filaments_. The stout chrysalis is green with golden markings. This butterfly has a bitter taste, and so is not molested by birds or insectivorous mammals. For this reason _Anosia plexippus_ has become very abundant and spread over a vast territory. Other butterflies which happen to resemble it share in this protection even though they have no disagreeable flavor, and this has given rise to the phenomena of _mimicry_, which is discussed elsewhere in this book. Another interesting thing about the Monarch is the fact that it does not hibernate in any stage; the eggs, caterpillars, and chrysalids die when the cold weather overtakes them, while the adults gather in great swarms and migrate southward, where they breed continuously throughout the winter. With the advent of warm weather the young southern Monarchs come north, deposit their eggs on northern milkweed, and the cycle begins again. THE HELICONIANS This is a tropical subfamily, and has only one representative within the borders of the United States. _Heliconius charitonius_, the Zebra butterfly, is a slender, long-winged, black-and-yellow species common along the roadsides of southern Florida. This butterfly has such an evil taste and odor that no known animal will eat it. The eggs are deposited upon the passion-flower vine; the young larva is hairy, but the mature caterpillar is provided with a great number of branching spines. The chrysalis is dark brown and of an odd shape; it makes a peculiar creaking sound by moving its abdomen. Another interesting fact about this Zebra butterfly is that the males are attracted to female chrysalids, and may be seen hovering about waiting for their mates to emerge. THE NYMPHALINAE This is the largest of all the subfamilies, numbering more than a hundred and seventy species in the United States. They are mostly large or of medium size, and include many of the commonest and most conspicuous butterflies we have. One of the most interesting members of this group is _Dione vanillae_, the Red Silverspot. The wings are bright red on the upper surface, with black veins and markings; the under side shows a spangled effect of brown and silver. The wings are unusually long, and the butterfly has a disagreeable odor which protects it from its enemies; these and other facts have led some lepidopterists to class this butterfly with the Heliconians. The eggs are reddish brown in color, and are found on the passion-vine; the caterpillar is marked with orange and drab, and bears six rows of branching spines. The chrysalis has an unusual form due to a pronounced dorsal depression; it is usually a grayish tan in color. _Dione vanillae_ is found in the whole southern half of the United States, being especially abundant about New Orleans, and in southern California. W. H. Edwards took a specimen at Coalburg, West Virginia, and it has been reported from as far north as Worcester, Mass. _Grapta interrogationis_, the Question Mark butterfly, is common in all parts of the United States except the Pacific coast region. The upper sides of both wings are reddish brown, spotted with dark brown and edged with a faint violet color. The peculiar angular shape of the fore wings, and the little tails on the hind wings, are the outstanding characteristics of the Question Mark and its relatives. The under side of the wings shows a mottled light brown, like a dead leaf; on the under side of the hind wing is found the silver mark resembling a Greek interrogation point (something like the English semicolon) which gave the butterfly its name. The eggs are deposited on elm trees, hop-vines, and several kinds of nettles. The caterpillar is reddish in color, covered with branching spines. The chrysalis is brown or greenish, with a conspicuous protuberance in the thoracic region. _Vanessa antiopa_, the Mourning Cloak butterfly, may be remembered as the first butterfly to be seen in the early Spring. The upper surface of the wings is a rich reddish purple, with a yellow border and a row of blue spots just inside it. The under side is gray, and blends perfectly with the dead twigs upon which the butterfly is accustomed to perch. The eggs are laid in clusters on the elm, willow, and poplar trees; the dark, spiny caterpillars live in small colonies, and spin a sort of web among the leaves of the food plant. The chrysalid is much like that of the Question Mark butterfly. In the autumn the Mourning Cloak crawls into a hollow tree or under a bit of loose bark and sleeps all through the winter, often flying in the Spring before the snow has melted, and long before the first leaves have appeared. _Junonia coenia_, the Peacock butterfly, is a medium-sized butterfly with an expanse of about two and one-fourth inches. The large eye-spots on both wings give it a characteristic appearance, very different from any other butterfly in this country. It occurs in all parts of the United States, but is somewhat rare in the northern part of its range. The dark green eggs are deposited on various kinds of plantain; the caterpillar is dark and covered with spines; the chrysalis generally light brown, and has a conspicuous depression in the ventral thorax. This butterfly is conspicuous for its pugnacity; it will drive away any other species which chances to approach, and even dart at stones or other objects thrown in the air. _Basilarchia disippus_, the Viceroy butterfly, looks very much like _Anosia plexippus_ the Monarch, except for a single transverse black band on the hind wings. The eggs are laid upon willow or poplar leaves; the caterpillar has no spines, but there are two club-shaped appendages just back of the head; the chrysalis is light gray with brown spots, and has a fin-like projection on back of the thorax. The Viceroy spends the winter in the larval state. When cold weather sets in the caterpillar anchors a leaf to the twig by means of silken threads, then rolls himself up in the leaf and sleeps until the following Spring. _Chlorippe celtis_, the Hackberry butterfly, is smaller than most of the common four-footed butterflies, its expanse being less than two inches. The general color of the wings is gray, but the outer part of the fore wings is black with broken rows of white spots. There is a little red tinge about an eye-spot in the fore wing, and five such spots are located near the outer edge of the hind wing. The female is slightly larger than the male, and somewhat less pronounced in color. The eggs are deposited in clusters on the hackberry trees; the caterpillar bears a pair of antler-like appendages on its head; the chrysalis is stockily built, with the head deeply notched. The Hackberry
{'title': 'Life Among the Butterflies by Vance Randolph', 'source': 'Project Gutenberg', 'lang': 'en'}