Chapter XII: Part II: The True Butterflies (6)
The little larvae remain together until after the third moult, at which time they are about half grown. In the more northern regions where they are found they are now likely to scatter about in search of quarters for hibernation. Having found suitable shelter, they remain through the winter to come forth early the following spring and feed upon the developing leaves of the hackberry trees. They continue to do this for a few weeks before they become full grown. They are then smooth-bodied, greenish worms about an inch and a half long, striped longitudinally in yellow and brown. The hind end of the body is forked in a curious fashion and the head is even more remarkable for the strange pair of tiny antlers projecting from it.
These full-grown caterpillars soon change to pale green chrysalids, lightly striped with longitudinal lines of yellow, with a distinctly pointed head. From these chrysalids butterflies emerge early in summer.
Evidently in the more Southern states there are two broods of these butterflies each year but there is great need of more precise knowledge in regard to them.
As is the case with so many other butterflies there is a dimorphic form, called _ocellata_, in which the outer half of the hind wing is very dark brown, with the eye-spot showing as black with red-brown circles.
_Synopsis of the Emperors_
_Goatweed Emperor_ (_Anoea andria_ or _Pyrrhanea andria_). Expanse 2 1/2 inches. Front outer angle of each front wing projecting into a falcate tip. Rear outer angle of each hind wing projecting into a distinct tail. General color burnt-orange with darker marginal bands, and in the female on the upper surface other sub-marginal markings.
_Gray Emperor_ (_Chlorippe celtis_). Expanse 2 inches. General color grayish brown with numerous markings of white and blackish. A distinct brown eye-spot on the upper surface of each front wing near the outer hind angle.
_Tawny Emperor_ (_Chlorippe clyton_). Expanse 2 inches. General color tawny brown with markings of black and yellowish white. No distinct eye-spot on upper surface of front wings.
THE MEADOW-BROWNS OR SATYRS
FAMILY _Agapetidae_
The Meadow-browns form one of the most distinctive family groups among all the butterfly tribes. They are characterized, at least so far as our eastern species are concerned, by their slender bodies and rather large wings, toned in various shades of brown, and marked chiefly with conspicuous and characteristic eye-spots. The larger veins of the front wings are swollen at the base. The caterpillars are rather slender and have a curious division of the last body segment into two parts, which gives them an appearance suggestive of the caterpillar of the Emperor butterflies, although the Meadow-brown caterpillars do not have, upon the head, the curious antlers borne by the Emperor larvae.
=The Common Wood-nymph or Grayling=
_Cercyonis alope_
In the development of our knowledge of both birds and mammals as found upon the American continent the experience in many cases has been essentially this: a bird or a mammal was first described from some well-known region of North America, commonly from specimens carried to Europe by early voyagers. Later other species of the same genus were brought to light by various explorers and given specific names. As each section was thus explored a new form differing markedly from the others was found and named. At a later period, when great collections were brought together so that one observer was able to make a careful survey of specimens from all parts of the continent, it was found that many of these species merged into each other through intergrading forms from regions between the localities of the original species. So it has come about that in the case of a large number of our birds and mammals we have geographical races distinctly recognized instead of separate species.
While the study of butterflies has by no means received the degree of attention which has been given the birds and mammals, it is already evident that a similar condition prevails with reference to many species. As the size of collections has increased and more careful studies have been made of the various forms from different regions it has been found in numerous cases that they intergraded to so great an extent that it is impossible to distinguish many species which were formerly considered entirely distinct. One of the most striking examples of this is found in the case of our common Wood-nymph, which is sometimes called the Blue-eyed Grayling. The form which is one of our most abundant butterflies in southern New England and many of the Eastern states was described as _Satyrus alope_ by the French naturalist Fabricius, who also described another species from the Southern states as _Satyrus pegala_, and a form found in northern Canada was described by the English entomologist Kirby as _Satyrus nephele_. Various other forms from isolated regions have been given specific names by other authorities. (_See plate, page 81._)
During recent years many collectors have gathered these butterflies from all parts of North America and many specimens have been grouped together in the more important collections. When this occurred it became easy to see that this is essentially a variable species which under varying climatic conditions has assumed slightly different forms, so that we have a good illustration of well-developed geographical races. The more important of these are indicated in the synopsis of the Meadow-browns on page 227.
_The Similar Life-histories_
One good indication that these varying forms all have a common origin is found in the remarkable unity of their life-histories. It is essentially the same in all. The mother butterflies lay eggs late in summer upon the leaves of grasses and perhaps other plants. About three weeks later these eggs hatch into small caterpillars that immediately become lethargic and begin their hibernating condition without eating any vegetation. They remain thus fasting until spring when, after the weather warms up sufficiently, they begin to feed upon grasses and perhaps other herbage. But they have lots of time in which to complete their growth and they are very moderate in their eating and their movements. They grow slowly so that they do not become mature as caterpillars until June. They then change to chrysalids to emerge as butterflies during July and August. The female butterflies remain upon the wing for some weeks before they begin to lay their eggs. We thus have in this case an adaptation to single-broodedness in practically all stages of the insect's life. The twelve months of the year must be passed and egg, larva, chrysalis, and butterfly each seems to try to do its part in prolonging its period of life.
These butterflies are especially common along streams and near the borders of woods, as well as in upland pastures and meadows. They are interesting creatures with characteristic manner of flight. They are by no means so easy to capture as one might think who sees them apparently going with slow, erratic motions from flower to flower. Mr. S. F. Denton, a collector of long experience, has written this interesting paragraph upon this point:
"As the flight of these insects is weak, they have been obliged to resort to a number of tricks to outwit their enemies. In capturing these butterflies the collector will very soon become acquainted with their modes of escape, which are very interesting and show no small amount of cunning, scarcely to be looked for in an innocent little butterfly. Their first plan of escape on being disturbed is to make directly for a clump of bushes into the thickest part of which they dive and there remain until the danger is past. If one is startled from the grass at some distance from a safe retreat and the collector overtakes him, he will immediately dodge backward and forward, at one time high in air and again low down near the grass tops, and in spite of his slow flight keeping well clear of the net. If the net is at last brought very close to him he will try his last desperate scheme to elude his pursuer and shutting his wings quickly together will drop into the grass, disappearing as if by magic. If it were not for the cunning of the frail little creatures they would doubtless have gone to the wall long ago in the struggle for existence."
=The Southern Wood-nymph=
_Cercyonis pegala_
This large southern butterfly is sufficiently distinct from the other Wood-nymphs to rank as a separate species. The yellow blotch has expanded into a large band extending practically across the front wings. On its upper surface there is one eye-spot in the male and two in the female. It is abundant in the extreme Southern states and has occasionally been taken much farther north.
=The Pearly Eye=
_Enodia portlandia_
Most butterflies are creatures of open country, basking freely in the sunshine and visiting flowers of many sorts for their nectar food. Some of them are found at times along the borders of woods and others seek the woods especially in autumn for the purpose of hibernation. This exquisite Pearly Eye, however, is distinctly a woodland species, being found only in little glades in the midst of woods and apparently seldom even seeking flowers for their nectar. It is commonly considered one of the rarest of American butterflies, but many collectors who have searched their regions carefully have been able to find small areas in which the butterfly is quite abundant. In such situations it may be looked for in all parts of the United States east of the western limits of the Mississippi Valley and south of Canada, except perhaps the lower part of Florida.
In northern regions this butterfly is single-brooded: the adults appear shortly before midsummer and continue on the wing through July and at least part of August. The eggs are laid some weeks after the butterflies emerge. The caterpillars feed upon grasses and apparently hibernate after they become well grown, changing to chrysalids the following spring in time to emerge as butterflies in early summer.
These Pearly Eyes have certain characteristics which are of especial interest. No other species presents such exquisite modulation of brown coloring arranged in beautiful circles upon both surfaces of the wings. The males possess, perhaps to a greater degree than any other of our native butterflies, the ability to give off a peculiar, pleasant aroma which is noticeable whenever the insects are collected and which at least one careful observer has been able to detect in the open air as the butterfly flew near.
For many years Mr. W. F. Fiske made a special study of the butterflies prevailing in the region of Webster, New Hampshire. His word picture of the haunts of the Pearly Eye is more adequate than any other which has been published and seems well worth quoting in this connection:
"I have found them in several localities, always in some numbers, but nowhere more abundant than in a little wooded glen in Webster. Here a scattering group of tall pines, a few thick hemlocks, and a young growth of miscellaneous deciduous trees fill up the space between two rather steep banks. A small trout brook follows close by one of these banks, and near the lower end of the glen, in a space kept clear of underbrush by the overshadowing influence of the pines and hemlocks, is a little spring, the overflow from which keeps the ground moist for some space on each side of the channel which it follows to the brook. This is the great meeting place of these butterflies; here they may be seen at almost any time in the day except in the early morning--when they seek the outskirts of the woods--until the shades of evening render their flitting forms indistinguishable. Half-way up the bank on one side, half shrouded in the dense growth of underbrush which is springing up around it, is an old apple tree upon which the sapsuckers work yearly. The wounded limbs, dripping with sap, are frequented by many forms of insect life, most noticeable among them this butterfly, and such refreshment added to the moisture which they suck from the margin of the spring is all that I have ever seen them partake."
=The Eyed Brown=
_Satyrodes canthus_
For delicacy of gray-brown color tones few butterflies can compare with this exquisite creature. It seems indeed to have succeeded in a modest attempt to obliterate itself, for even when the spread wings are placed against a clear white background they can scarcely be called conspicuous and it is very probable that when the butterfly is at rest in its native haunts, with wings closed together so that only the very delicate light brown color-tones of the under surface are revealed, it actually becomes invisible.
The upper surface of the wings is broadly washed with a gray-brown color which runs into a suggestion of a lighter band near the outer margin of the front pair. The upper surface of the hind wings is almost uniformly washed with this same brown color which is interrupted only by very fine, double lines at the outer margin and a sub-marginal row of delicate _ocelli_ which are larger than the somewhat similar sub-marginal row of eye-spots on the front wings. The under surface is much lighter in color, with distinct striations extending across the main surface of both wings from front to back and with some very attractive _ocelli_ arranged as a sub-marginal series each with a central white eye.
This is distinctly a northern species, having rather a limited range in Canada and New England. It extends south to Pennsylvania and Ohio and westward to Wisconsin and Iowa. It is more abundant in northern than in southern New England but it is often overlooked by collectors who are not familiar with its haunts. It is especially likely to be found among the tall grass of swamps and brooks running through lowlands. One of the best ways to discover it is to beat the grasses in such situations.
The life-history of the Eyed Brown is fairly well known. The eggs are laid chiefly on grasses and probably at times upon the grass-like sedges. The larvae feed upon these plants and become nearly full grown before winter sets in. They then hibernate in this larval stage and the following spring complete their growth and change to chrysalids in time for the butterflies to emerge in June. There is but one brood a year.
=The White Mountain Butterfly=
_Oeneis norna semidea_
To appreciate the extraordinary distribution of this notable species one must let his fancy carry him back a million years or so until he reaches that old time when the whole northern part of the American continent was covered with an icy coating. Then he must follow the gradual retreating of the ice northward, carrying with it wonderful changes in climate and along with these climatic changes taking northward many plants and animals which were adapted to the cool temperature along the borders of the glacier. As the ice cap retreated most of these arctic forms retreated with it, and all along the lower levels they were replaced by others migrating from the south so that gradually there came about the distribution of plants and animals as we find them to-day.
When, however, the glaciers left the higher elevations of the White Mountains and the Rocky Mountains there were at the summits small areas in which the climatic conditions were of very much the same arctic character as prevailed along the margin of the ice cap. Consequently conditions were here favorable for the continuation of many of the arctic species which had disappeared from the warmer, lower levels. It was as if we had a great sea of air of a certain warmth and rising above this the islands of the mountain tops, these islands retaining the same arctic features as otherwise are found much farther northward.
Among the animals thus left stranded by the retreating ice cap this White Mountain butterfly has perhaps attracted the most attention from scientists. It is a butterfly of moderate size which shows in every phase of its structure and its life-history the results of the long process of adaptation to its unique environment. It has been carefully studied by many observers and has been considered one of the most desirable trophies by every collector of insects. As a result, notwithstanding its isolation and the difficulty of studying it, its life-history is better known than that of many a common and widely distributed species.
To appreciate the facts in regard to the structure and life of this butterfly one must know that its habitat is confined to a thousand feet or so at the summits of the mountain, that in this area there are no trees or even shrubs worth mentioning, and that the surface of the mountain is covered with rocks between which grow a few stunted sedges and over which grows the ever-present reindeer moss. It is a bleak, bare, gray environment, constantly swept by terrific winds, where snow is seen in August and is likely to remain until June. So the summer season is of briefest duration and the climatic conditions are so severe that one can only wonder how a fragile creature like a butterfly is able to survive the twelve long months.
_Habits and Life-history_
From a first glance at the mottled gray-brown wings of these insects one would guess that here was a distinctive example of obliterative coloring, and it is true as all observers testify that when the butterfly lights upon the stones and turns sideways, as apparently it does habitually in deference to the force of the wind, it becomes very difficult to see, for the wings are closed and only the rounded, mottled under surface shows. It appears also to have the habit of some of the Graylings when hard pushed of simply closing its wings and dropping to the ground feigning death. In deference also to the winds its flight is just above the surface. Doubtless if it rose high in the air it would be swept away to lower regions where evidently it is unable to survive for long periods.
THE ZEBRA BUTTERFLY
On orange leaves and blossoms. (Reduced)]
On clematis seed-fruits
PHOTOGRAPHS OF A PET MONARCH BUTTERFLY]
These butterflies appear early in July and continue on the wing for several weeks. They lay their small eggs upon or near a species of sedge which is abundant on these alpine summits. About two weeks later the eggs hatch into sluggish little caterpillars which feed upon the sedge leaves, apparently eating only at night and hiding in crevices between stones by day. As one would expect from the prevailing low temperatures these caterpillars grow very slowly and apparently a large proportion of them require two years to complete their development. There seems to be some uncertainty in regard to this phase of the insect's life-history, but most entomologists are of the opinion that some of the butterflies mature in one year while others require two years: that is, the broods are both annual and biennial. There is no doubt that the insect hibernates as a caterpillar, and if this statement about the number of broods is correct some of the caterpillars hibernate when very small, and recently hatched from the egg, while others hibernate when nearly full grown.
The full-grown caterpillars change to chrysalids beneath the shelter of the small stones in practically the same sorts of situation which they have chosen for hiding at night or for hibernation through the winter. Here without any button of silk or silken loop and with scarcely a suggestion of a silken cocoon they change to chrysalids, generally about the first of June. They remain in this condition for perhaps three or four weeks when they come forth as butterflies.
=The Arctic Satyr=
_Oeneis norna jutta_
This is another butterfly of decided interest because of its geographical distribution. It is normally an inhabitant of the Far North, extending around the North Pole over parts of three continents. Apparently, the only place in the United States where it occurs is a bog a little north of Bangor, Maine. This locality is called the Orono-Stillwater bog and is the only place where collectors have been able to find this species.
* * * * *
An even more local insect is another of these mountain butterflies found by H. H. Newcomb on Mount Katahdin, Maine. So far as known this species is confined to the higher portion of this mountain and so is even more distinctly localized than the White Mountain butterfly. It is called the Katahdin butterfly (_Oeneis norna katahdin_).
=The Little Wood Satyr=
_Cissia eurytus_
This elfin creature has well been named the Little Wood Satyr, although under our modern conditions it is often found in fields and along hedgeroads rather than in the woods. It has, to a marked degree, the delicacy of structure of its allies and its small size serves to emphasize this appearance. It has also a rather general distribution west to the Mississippi Valley, extending from the corner of Dakota, south through Nebraska, Kansas, and central Texas, and north to Wisconsin, Michigan, and New England. It occupies the whole of the United States east and south of the lines thus indicated.
The life-history of this species is very similar to the Common Grayling. The butterflies appear in early summer, deposit their eggs upon grasses, and the resulting larvae feed upon the grasses and grow slowly through the weeks of summer. They become nearly full grown by autumn and hibernate in this condition in such shelter as they can find at the soil surface. The following spring they come forth, probably feeding for a short time, and change to chrysalids in time to emerge as butterflies in May and early June. Practically all observers emphasize the fact that the butterflies are abundant only late in spring or early in summer, generally disappearing before the middle of July. There is thus but one brood a year.
_Other Meadow-browns_
The _Gemmed Brown_ (_Neonympha gemma_) is a small southern species remarkable for the plainness of its gray-brown wings which are marked on the upper surface only with two or three dark spots on the middle margin of each hind wing. There are two broods a year.
The _Georgia Satyr_ (_Neonympha phocion_) is another small southern form, remarkable for the four elongated eye-spots on the lower surface of each hind wing. The shape of these spots distinguishes it at once from the _Carolina Satyr_ (_Cissia sosybius_) in which the eye-spots are rounded.
_Synopsis of Meadow-browns_
_Pearly Eye_ (_Enodia portlandia_ or _Debis portlandia_). Expanse 2 1/4 inches. Eyes hairy. Outer margin of hind wings projecting in a noticeable angle. Brown with many distinct eye-spots on both surfaces of wings.
_Eyed Brown_ (_Satyrodes canthus_ or _Neonympha canthus_). Expanse 2 inches. Eyes hairy. Margin of hind wings rounded, without an angle. Both surfaces of wings pale brown with four distinct blackish eye-spots on each front wing near the margin. Five or six such spots on each hind wing.
_Common Wood-nymph_ or _Grayling_ (_Cercyonis alope_). Expanse 2 inches. Eyes not hairy. Eye-spots on front wings, but not on upper surface of hind wings. The chief geographical races of this abundant species are indicated below, although in regions where the forms overlap many intermediate hybrids occur.
_Blue-eyed Grayling_ (_Cercyonis alope alope_). A large yellowish-brown blotch near outer margin of each front wing, above and below, with two distinct eye-spots in middle spaces of the blotch. A southern race extending north to central New Hampshire, Michigan, and Wisconsin.
_Dull-eyed Grayling_ (_Cercyonis alope nephele_). The yellowish brown blotch obsolete or nearly so, but eye-spots present. A northern race extending southward only to central New Hampshire, Michigan, and Wisconsin.
_Maritime Grayling_ (_Cercyonis alope maritima_). Similar to the type form, but with the yellowish blotch tinged with reddish. A race found only near the seacoast.
_Southern Wood-nymph_ (_Cercyonis pegala_). Expanse 3 inches. Eyes not hairy. General color brown with an orange-yellow blotch near outer margin of each front wing above and below with one eye-spot in middle space of the blotch on the male, and two on the female.
_Little Wood-satyr_ (_Cissia eurytus_ or _Neonympha eurytus_). Expanse 1 1/2 inches. Eyes not hairy. General color fawn-brown with two eye-spots on upper surface of each front wing and several on each hind wing.
_Gemmed Brown_ (_Neonympha gemma_). Expanse 1 1/4 inches. Eyes not hairy. General color mouse-brown with no markings on upper wing surface except a rather indistinct pair or more of spots next the margin of the middle of each hind wing. Under surface indistinctly striped with rusty lines and a few brown and silvery spots on the hind wings directly beneath the spots on the upper surfaces. Occurs in Southern states.
_Georgia Satyr_ (_Neonympha phocion_). Expanse 1 1/4 inches. Distinguished from the related species by the four distinct eye-spots on lower surface of each hind wing, these spots being transversely elongated rather than round. Occurs in Southern states.
_Carolina Satyr_ (_Cissia sosybius_). Expanse 1 1/4 inches. Distinguished by the row of round eye-spots near outer margins of lower wing surface. Occurs in Southern states.
THE HELICONIANS
FAMILY _Heliconidae_
This is a tropical family with only a single species migrating northward to our Southern states. The butterflies of this group are characterized by having the wings so long and narrow that their length is usually twice as great as their width. The front legs in both sexes are so poorly developed that they are considered a modification approaching the complete dwarfing found in the Brush-footed butterflies.
=The Zebra Butterfly=
_Heliconius Charitonius_
While the butterflies of temperate North America show many examples of marvelous beauty and coloring, one must go to the tropics to see the culmination of what nature has done in painting the outstretched membranes of butterfly wings with gorgeous colors. The great butterfly tribes that swarm in tropical forests seldom reach our temperate clime, and even when they do they are likely to show only a suggestion of the splendid size and rich coloring to be seen farther south. The Zebra butterfly (_Heliconius charitonius_) belongs to one of these tropical tribes. It shows its affinities by its coloring and the curious shape of its wings. In most of our northern butterflies, the wings are about as long as they are wide, but in the tropical family, _Heliconidae_, they are very much longer than wide. This gives the insect an entirely different look from our common forms so that one recognizes it at once as a stranger within our gates. Indeed, it does not penetrate far into our region, being found commonly only in Florida and one or two other neighboring states, its principal home being in tropical America.
The Zebra butterfly is well named. Across the brownish black wings there runs a series of yellow stripes, three on each front wing and one on each hind wing, with a sub-marginal row of white spots on each of the latter. The under surface is much like the upper, except that the coloring is distinctly paler. It is very variable in size: some specimens may be but two and a half inches across the expanded wings, while others are four inches. (_See plate, page 224._)
The Zebra caterpillars feed upon the leaves of the passion flower. When full grown they are about an inch and a half long, whitish, more or less marked with brownish black spots arranged in transverse rows, and partially covered with longitudinal rows of barbed black spines. They change to chrysalids which are remarkable for their irregular shape, with two leaf-like projections on the head which the insect can move in a most curious fashion.
One of the most notable things about this insect is the fact that the male butterflies are attracted to the chrysalids of the females even before the latter emerge. Many observers have reported upon this curious phenomenon and have recorded experiments demonstrating that it is a general habit with the species.
_The Roosting Habits_
The adult butterflies flock together at night and rest upon the Spanish moss which festoons so many of the trees in the Far South, or upon dead branches. They take positions with heads upward and wings closed, many of them often flocking together to roost, and wandering out to the near-by fields when the morning sun gives them renewed activity. But these butterflies are essentially forest insects. Reliable observers have noticed that when one emerges from a chrysalis it flies up in the air and makes straight for the nearest woods. Others have noticed that when a butterfly in a field is alarmed it also makes for the woods. And in the regions where the species is abundant the butterflies are most likely to be found in paths and glades in the forest. Thus they show the influence of their ancestral habitat in the tropical wilderness.
There seems to be a certain amount of ceremony attending the flocking together at night for roosting purposes. A famous English naturalist, Philip Henry Gosse, saw the performance in the West Indies many years ago and described it in these words:
"Passing along a rocky foot-path on a steep wooded mountain side, in the Parish of St. Elizabeth (Jamaica), about the end of August, 1845, my attention was attracted, just before sunset, by a swarm of these butterflies in a sort of rocky recess, overhung by trees and creepers. They were about twenty in number, and were dancing to and fro, exactly in the manner of gnats, or as _Hepioli_ play at the side of a wood. After watching them awhile, I noticed that some of them were resting with closed wings at the extremities of one or two depending vines. One after another fluttered from the group of dancers to the reposing squadron, and alighted close to the others, so that at length, when only two or three of the fliers were left, the rest were collected in groups of half a dozen each, so close together that each group might have been grasped in the hand. When once one had alighted, it did not in general fly again, but a new-comer, fluttering at the group, seeking to find a place, sometimes disturbed one recently settled, when the wings were thrown open, and one or two flew up again. As there were no leaves on the hanging stalks, the appearance presented by these beautiful butterflies, so crowded together, their long, erect wings pointing in different directions, was not a little curious. I was told by persons residing near that every evening they thus assembled, and that I had not seen a third part of the numbers often collected in that spot."
THE MILKWEED BUTTERFLIES
FAMILY _Lymnadidae_
So far as the great majority of readers of this book are concerned, this family includes but one species--the familiar Monarch or Milkweed butterfly. In the Southern states there is another--the Queen--and in Florida, still a third. The distinguishing characteristics are found in the dwarfed, useless front legs and the absence of scales upon the antennae.
=The Monarch=
_Anosia plexippus_
From June until October one may often see the stately Monarch flitting leisurely about over fields and meadows. It is one of the largest and most distinctive of these "frail children of the air" and may be easily recognized by its resemblance to the picture opposite page 241. The veins of the wings are heavily marked in black, with large white dots upon the black bands along the margin. The color of the rest of the wings both above and below is reddish brown.
These butterflies come from the South in spring or early summer. They find milkweed plants and lay their eggs upon the leaves. These eggs soon hatch into small white and black caterpillars that feed upon the milkweed leaves and grow rapidly. One is likely to find them throughout most of the summer, wherever a milkweed shows partially eaten leaves. Bring in the half-grown caterpillars, place them in an open vivarium, and furnish fresh leaves every day or two. The caterpillars will soon mature and change to beautiful green chrysalids with golden markings. This chrysalis has been called "the glass house with the gold nails." (_See plates, pages 32-33, 241._)
About two weeks later the glass house will burst open and the butterfly emerge. It will rest an hour or two while its wings and body harden and then it will want to fly away. It is not so anxious to do this, however, as most butterflies. If one is kept beneath a good-sized bell-glass, or in a glass-covered box, or even in a closed room, and fed with sweetened water it will soon become so tame that it will perch on one's finger and suck nectar from a flower held in one's hand. On this account it is a particularly desirable butterfly for the amateur photographer to cultivate, because he can easily get many interesting and beautiful pictures by posing the butterfly on different flowers.
_The Change from Caterpillar to Butterfly_
The change from the caterpillar to the butterfly is easier to watch in this species than in most others. The full-grown caterpillar spins--sometimes on the under surface of the milkweed leaf, sometimes elsewhere--a little mat of silk in which it entangles the hooked claws of its hind feet. Then it lets go with its fore feet, and hangs downward with the front end of its body curled upward. In this position it remains for some hours--perhaps a day--the body juices gravitating downward and causing a swollen appearance on the lower segments. Then the skin splits apart and is wriggled off by the contortions of the body. When it finally drops away, there is left a strange-looking creature, broader below than above. This is a transition stage that lasts but a very short time: soon the form is entirely changed so that the broadest part is above instead of below. The definite outline of the chrysalis is soon taken on, the outer tissues hardening into a distinct covering. The insect is now a beautiful green with wonderful golden spots upon its surface and a few black spots just below the black "cremaster" by which the chrysalis is connected with the web of silk upon the leaf.
In this quiet chrysalis the insect remains for nearly a fortnight. Then the structure of the forthcoming butterfly begins to show through the thin outer covering and you know that the period of the chrysalis is nearly ended. If you keep watch you will probably see the sudden bursting of the outer envelope and the quick grasping of its surface by the legs of the newly emerged butterfly. Its wings at first are short and crumpled, bearing little resemblance to those of the fully developed butterfly. But as it hangs there with one pair of legs holding to the empty chrysalis and the other to the leaf above, the wings rapidly lengthen, hanging limply downward, and the body juices penetrate the veins. A little later they expand in the other direction, the hind wings reaching full size before the front ones do. Finally both pairs of wings are fully expanded, and the butterfly is likely to walk to the top of the support, where it rests for an hour or two while its tissues harden, before it attempts to fly.
In early autumn out of doors these butterflies start southward on their long journey. They often gather in great flocks and roost at night on wayside shrubs and trees. At this season it is easy to catch them in an insect net and bring them indoors for pets. They live for a long while and lend interest and beauty to living room or window garden. To the photographer they offer opportunities for attractive indoor pictures. (_See plates, pages 32-33, 160, 225._)
=The Queen=
_Anosia berenice_
The general form and color patterns of this fine butterfly show at once that it is related to the Monarch. Its general colors are chocolate-brown and black, dotted and spotted with white. The eggs are laid upon milkweed and the life-history is much like that of the Monarch. One of the most interesting facts in connection with this species is that it seems to be mimicked by the Vicereine butterfly in the same way that the Monarch is mimicked by the Viceroy.
THE SNOUT BUTTERFLIES OR LONG-BEAKS
FAMILY _Libytheidae_
One has a suggestion of Hobson's choice in the common names of this unique family. If Snout butterflies does not seem sufficiently elegant as a descriptive phrase for such delicate creatures, he can call them the Long-beaks, until he sees that this also is inadequate. As a matter of fact both are misnomers, for the projection from the head that gives them these names is neither a snout nor a beak. It is simply a pair of palpi unusually developed, which perhaps in an early stage of butterfly history served a useful purpose. At present, however, they serve chiefly to set the few owners apart from the other butterflies in the system of classification; although possibly they may also serve the butterfly by helping to give the impression of a leaf attached to a twig. (_See plate, page 240._)
=The Snout Butterfly=
_Hypatus bachmani_
There is a peculiar interest in any form of animal life which can be definitely traced far back through the geologic ages. In nearly every group of living creatures there are certain types which scientists have found were once abundant but which now are on the wane. As a rule these are better represented in the museums through fossil species than by those now living. To a considerable extent also such forms are likely to present various features which mark their primitive condition and the living allies have peculiarities which set them off as distinct from those of their own relations which have been modeled in a more modern fashion. Among the mammals the curious marsupials, of which our southern opossum is an example, furnish good illustrations of this general truth. Among the birds the curious little Least Bittern is an example. Among the butterflies the strange Snout butterfly is by far the best example.
These Snout butterflies, of which only two species are now living in North America, are the sole representatives with us of the family _Libytheidae_ or the Long-beaks. Only one of these species occurs to any extent at least north of Texas. It is the curious little creature called the Snout butterfly. It has a strange appearance due to the angular outline of both front and hind wings and the long palpi which project forward from the head in a way to attract attention. The common name is due to these projecting palpi. Even the coloring is primitive, the general tone of the wings being blackish brown, distinctly marked with white and orange spots. The under surface is less primitive in its coloring, being toned in iridescent grayish brown in a way to suggest protective coloring, except in that part of each front wing which is not hidden when the insect is at rest. This shows the white and orange-brown markings.
Some years ago there were found in certain fossil deposits in the West about a dozen species of fossil butterflies. It is strange indeed that these ethereal creatures should be fossilized at all. One would think it scarcely possible that they could be so preserved that a million years after they had died man should be able to study them, determine to what families they belonged, and even guess with a high probability of accuracy upon what leaves their caterpillars fed. This little collection of fossil butterflies was studied by one of the great American authorities on living butterflies, the late Samuel H. Scudder, who said of them: "They are generally preserved in such fair condition that the course of the nervures and the color patterns of the wings can be determined, and even, in one case, the scales may be studied. As a rule, they are so well preserved that we may feel nearly as confident concerning their affinities with those now living as if we had pinned specimens to examine; and, generally speaking, the older they are the better they are preserved."
A curious fact is that out of the comparatively few species of these fossil butterflies two were easily recognized as members of this Long-beak family. They were given special scientific names and undoubtedly were closely related to the Snout butterfly which is still flying every year in various parts of the United States. Our modern species lays its eggs upon the leaves of hackberry and in these geologic deposits of that far-gone era there have been found well-preserved leaves of old hackberry trees, upon which it is extremely probable that the caterpillars of these ancient Long-beaks fed. What an opportunity for a modern collector of butterflies to work his fancy, as he thinks of those old times when these fossil creatures were flying in the sunshine, depositing their eggs upon the leaves of trees that made up landscape pictures probably very different from those of to-day! And how he wonders what flowers these butterflies visited for their nectar food, what birds chased them from tree to tree, and what mammals wandered through those ancient forests. What a suggestion also it gives of the continuity of life upon our old earth to realize that these butterflies of to-day are carrying on their brief existence in practically the same way that these forbears of theirs did so many millions of years ago.
Another way in which these butterflies are peculiar is the fact that the females have six well-developed legs while the males have only four. As already indicated the caterpillars feed upon hackberry. When full grown they are about an inch long, dark green, striped with yellow, with two blackish tubercules on the second ring behind the head. They apparently pass the winter in the chrysalis stage. The butterflies are likely to be found along the borders of brooks or streams running through woods, or along the margins of the forest. Occasionally they become abundant in certain localities, but on the whole they are rare and highly prized by collectors.
THE METAL-MARKS
FAMILY _Riodinidae_
This small family of very small butterflies contains five genera and a dozen species found in the United States and Mexico. Only two, however, occur in the eastern region and only one extends much north of the Gulf states. Aside from certain peculiarities of the wing-venation (a costal and a humeral vein on the hind wings) these Metal-marks may be known by their minuteness and the bright metallic markings on the brown wings.
Both our eastern species belong to the genus _Calephelis_. The Small Metal-mark (_C. caenius_) has been collected in Florida and Georgia. The wings are rusty red on both surfaces, brighter below than above, and marked with blackish spots that almost converge to form stripes; in addition to which there are, beyond the middle of each wing, two lines made by special scales that glisten with a steel glitter. The wings expand only about three quarters of an inch. So far as I can learn, the egg, larva, or pupa have never been described.
The Large Metal-mark is called by science _Calephelis borealis_, but it deserves the latter name only in the sense that it is more northern than its allies. It has been collected as far north as New York and Michigan, but it seems to be very seldom found, at least in eastern regions. It expands a little more than an inch. The general color of the wings is yellowish brown, marked with blackish dots and lines, together with rows of steely spots on the under surface. In this case also the life-history is unknown.
THE SNOUT BUTTERFLY IN FLIGHT AND AT REST]
GIANT SWALLOWTAIL JUST OUT OF THE CHRYSALIS]
THE MONARCH BUTTERFLY
Caterpillar feeding; caterpillar hung up for pupation;
chrysalis, and adult]
THE GOSSAMER-WINGS
FAMILY _Lycaenidae_
The daintiest and most delicate of all our butterflies are included among the Gossamer-wings. Their bodies are small and slender, their antennae ringed with white and almost threadlike, their wings thin and of exquisite beauty. Many of them are marked with the slenderest of tailed projections from the hind wings. When the face is viewed from in front it is seen to be much narrower than its height. At the insertion of the antennae the eyes are notched, and they are also more or less surrounded with white scales. Most of the caterpillars have oval, slug-shaped, smooth bodies, with the under surface flattened, and very small heads, which in many species can be extended by means of an extensile neck. The chrysalids are held in place by silken threads both at the tail and over the middle. They are rounded, short, and stout.
Notwithstanding their small size, the Gossamer-wings are among the most spritely of all our butterflies. They seem indeed winged sprites, playing everywhere, in fields and open woods, along roads, lanes, and brooks, in dooryards and gardens--wherever, in fact, a bit of open space invites their presence. Not alone upon the wing but even when at rest does their liveliness appear. For most of these butterflies have the curious habit of keeping the hind wings in motion after alighting, rubbing them against each other in a vertical plane or "moving them backward and forward when half expanded." These habits are so fixed that when one sees a butterfly thus engaged one can pretty certainly conclude it is a member of this family.
The Gossamer-wings are commonly separated into three rather distinct tribes--the Hair-streaks, the Coppers, and the Blues. The characteristic features are these:
Three branches arising from the radius of each front wing. Under surface of hind wing commonly marked with threadlike streaks: the Hair-streaks.
Four branches arising from the radius of each front wing. Under surface of hind wing commonly marked with spots rather than lines.
Colors brownish red: The Coppers.
Colors blue: The Blues.
THE TRIBE OF THE HAIR-STREAKS
The Hair-streaks are small butterflies with the eyes notched to allow for the insertion of the bases of the antennae. The name is given on account of the fine, hair-like markings which extend across the under surface of the hind wings. In many species there is a tailed projection or two on the hind inner margin of the hind wing. The caterpillars are remarkable for the small head, so connected with the body that it can be pushed forward in a characteristic way.
The Hair-streaks are among the most exquisite and delicate of all our butterflies. A large proportion of them have the upper surface of the wings toned in beautiful hues of grayish brown and the under surface lighter gray, marked with dots and stripes, some of which are brilliant in coloring. A few of the larger species are brilliantly iridescent in purples, blues, and greens, marked with black. The males have well-developed scent-pockets in many species, these being commonly along the front border of the front wing.
A very interesting suggestion in regard to the possible function of the curious tail projections was made nearly a hundred years ago by some English entomologists and has since been discussed at considerable length in various publications. It is that the slender tails, together with the enlargement of the wing just back of them, give the impression of a false head. Along with this unusual development of the wing is to be considered the fact that these butterflies nearly always alight head downward so that the false head, furnished with what seem to be waving antennae, takes the place that would naturally be occupied by the true head. Instances have been reported in which this false head has apparently been nipped off by a lizard and much evidence has accumulated to indicate that this curious device may be a real protection in many cases. Of course, the loss of the tails and the part of the wings adjacent would be comparatively insignificant. In most cases, these projections on the wings are held at right angles to the plane of the wing.
While nearly half a hundred species of Hair-streaks have been found in North America, only a few of these are sufficiently abundant to require discussion in this little book.
=The Great Purple Hair-streak=
_Atlides halesus_
It seems something of a reflection on the activities of American entomologists to say that, after the lapse of more than a century since Abbott studied the insects of Georgia, our knowledge of the early stages of two of the largest Hair-streak butterflies is still confined to the observations he made. Yet this is true, and one of them--the Great Purple Hair-streak--is the largest species of the group that occurs in the eastern United States. The other is the White-M Hair-streak.
The Great Purple Hair-streak is a beautiful, iridescent blue creature, as seen from above, with blackish borders around the blue. As seen from below, the wings are dark brown, with red spots near the body. The two tail-like projections are quite long. It is very large for the group to which it belongs, measuring nearly two inches across the expanded wings. It is a tropical form, extending into our southern borders from California to Florida and occasionally occurring north as far as southern Illinois. The larvae feed on oak. (_See plate, page 256._)
=The White-M Hair-streak=
_Eupsyche M-album_
The White-M Hair-streak is about two thirds the size of the Great Purple species with less blue and more black on the upper wing surface. The hind tail is slender and well developed, and the angle of the wing just back of it is rounded out in an unusual fashion. The lower surface of the wing is of a general grayish brown color, marked by a white stripe, which takes the form of the letter M: hence its name. This is also a southern species occurring at times as far north as Ohio and even Atlantic City, New Jersey. The caterpillars feed upon the leaves of oak and Astragalus or milk vetch.
There is also a third species of this group of whose history we are ignorant except for Abbot's observations. It is an exquisite little butterfly called the Least Purple Hair-streak (_Calycopis cecrops_) and is apparently a tropical form which has spread into our Southern states. It is especially beautiful because of the brilliant red and white lines running across the under surface of both wings. It occurs as far north as West Virginia and Kentucky and ranges westward at least to the Mississippi Valley.
=The Gray Hair-streak=
_Uranotes melinus_
This exquisite little creature is capable of surviving under a great variety of climatic conditions. It ranges from New Hampshire to Florida and Central America, but apparently occurs only rarely north of the United States. Perhaps the most distinctive feature in the female is the orange spot just in front of a pair of tiny tails on each hind wing, the rear one being curiously curved and about three times as long as the other. In the male the shorter tail is absent. The general color of the upper surface is a dark bluish gray, relieved on the margin of each hind wing by a few white dots and the orange spot already mentioned. The under surface is much lighter gray, distinctly marked with two dark brown lines near the margin, the outer line little more than a row of spots and the inner line with a white edge. (_See plate, page 257._)
These small butterflies lay tiny though beautiful eggs upon a variety of plants. The eggs hatch into curious little caterpillars that have the appearance of slugs with small heads which can be extended as if the little creature had really a rubber neck. The object of this extensile head is seen when one finds the larvae feeding upon the fruits or the seed-pods of its various food plants--hawthorn, hop, hound's-tongue, and St. John's-wort. The caterpillar is able to thrust its jaws into the interior of the seed-pods and devour their contents. There seem to be generally two broods in a season, even in the more northern parts of its range, while toward the south there are probably at least three broods. The butterflies are found upon the wing almost any time in summer, especially from early June until late in August.
=The Banded Hair-streak=
_Thecla calanus_
This is one of the most familiar of the delicate little butterflies grouped in the genus _Thecla_. It occurs rather commonly in a great stretch of territory extending from Maine, west to Nebraska, south to New Mexico and Texas, and east to Alabama and Georgia. It also occurs in a limited area on the coast of California. The general color of the upper surface is a dark brown, which in the male is marked near the front edge of the fore wings with a distinct gray patch of scent scales. The under side is similar in color to the upper except that the outer half of the wing is marked by two series of broken lines in white, blue, and brown and a brilliant bit of coloring just in front of the tail projection of the hind wings; this coloring shows beautiful tones of red, blue, and black.
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Butterflies Worth KnowingChapter XII: Part II: The True Butterflies (6)
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