The Butterfly Book - Part 9
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Part 9

_Early Stages._--Unknown.

Reakirt says that this b.u.t.terfly occurs about Los Angeles, in California, and the statement has been repeated by numerous authors, who have apparently based their a.s.sertions upon Reakirt's report. I have no personal knowledge of the occurrence of the species within our borders.

It is very abundant, however, in the warmer parts of Mexico and Central America, and it may possibly occur as a straggler within the United States.

Genus DIRCENNA, Doubleday

_b.u.t.terfly._--Medium-sized b.u.t.terflies, for the most part with quite transparent wings. The most characteristic features of this genus, separating it from its near allies, are the thread-like front feet of the females, furnished with four-jointed tarsi (Fig. 83), the very hairy palpi, and the wide cell of the hind wing, abruptly terminating about the middle of the wing. Furthermore, in the male s.e.x the hind wing is strongly bowed out about the middle of the costal margin, and the costal vein tends to coalesce with the subcostal about the middle.

[Ill.u.s.tration FIG. 83.--Fore leg of _Dircenna klugii_, ?, greatly magnified.]

_Early Stages._--Very little is as yet known about the early stages of these insects, and what has been said of the characteristics of the caterpillars and chrysalids of the subfamily of the Ithomiinae must suffice us here.

[Ill.u.s.tration FIG. 82.--Neuration of the genus _Dircenna_.]

This genus numbers a large array of species which are found in the hottest parts of the tropics of the New World. They fairly swarm in wooded paths amid the jungle of the Amazonian region, and no collection, however small, is ever received from those parts without containing specimens belonging to the group.

(1) =Dircenna klugii=, Hubner, Plate VIII, Fig. 1, ? (Klug's Dircenna).

_b.u.t.terfly._--Fore wings transparent gray, broken by clear, transparent, colorless spots at the apex, on the outer borders, and on the middle of the wing. The inner margin of the fore wing is black. The hind wings are transparent yellowish, with a narrow black outer border marked with small whitish spots. The body is black, with the thorax spotted with white. Expanse, 2.75 inches.

The specimen figured in the plate is from Mexico. Whether the insect has ever been taken within the limits of the United States is uncertain. It is another of the species attributed to our fauna by Reakirt, but which since his day has not been caught in the nets of any of the numerous b.u.t.terfly-hunters who have searched the region in which he said it occurs. It may, however, be found upon the borders of Mexico, in the hotter parts of which country it is not at all uncommon. The "gentle reader" will kindly look for it when visiting Brownsville, Texas, and southern California, and, when finding it, herald the fact to the entomological world.

SUPERSt.i.tIONS

"If a b.u.t.terfly alights upon your head, it foretells good news from a distance. This superst.i.tion obtains in Pennsylvania and Maryland.

"The first b.u.t.terfly seen in the summer brings good luck to him who catches it. This notion prevails in New York.

"In western Pennsylvania it is believed that if the chrysalids of b.u.t.terflies be found suspended mostly on the under sides of rails, limbs, etc., as it were to protect them from rain, there will soon be much rain, or, as it is termed, a 'rainy spell'; but, on the contrary, if they are found on twigs and slender branches, that the weather will be dry and clear."--FRANK COWAN, _Curious History of Insects_, p. 229.

SUBFAMILY HELICONIINae (THE HELICONIANS)

"Men, like b.u.t.terflies, Show not their mealy wings but to the summer."

SHAKESPEARE, _Troilus and Cressida_, act iii, sc iii

Medium or large-sized b.u.t.terflies, with the fore wings twice as long as they are broad; the hind wings relatively small and rounded upon the outer margin; without tails. The palpi are produced. The antennae, which are nearly as long as the body, are provided at the tip with a gradually tapering club, thicker and stouter than in the Ithomiinae, and are clothed with scales on the upper surface. The fore legs are very feebly developed in both s.e.xes. The eggs are cylindrical, twice as high as wide, tapering rather abruptly toward the apex, which is truncated; they are ribbed longitudinally, with strongly developed cross-ridges, giving the egg a somewhat pitted appearance. The caterpillar, when emerging from the egg, has the head somewhat larger than the body; each segment is clothed with hairs, which upon the first moult are replaced by branching spines. The caterpillar, when it reaches maturity, is provided with six branching spines on each segment. The chrysalis is very peculiar in shape, and is strongly angulated and covered with curious projections, which cause it to somewhat resemble a shriveled leaf.

[Ill.u.s.tration FIG. 84.--Neuration of the genus _Heliconius_.]

These b.u.t.terflies are extremely numerous in the tropics of the New World, and are there represented by a number of genera which are rich in species. Most of them are very gaily colored, the prevalent tints being black banded with yellow or crimson, sometimes marked with a brilliant blue l.u.s.ter. They are evidently very strongly protected. Belt, in his "Naturalist in Nicaragua," tells us that birds and other animals observed by him invariably refused to eat these b.u.t.terflies, although they swarm in the forests; and he vainly endeavored to induce a monkey which was very fond of insects to eat them, the creature revealing by his grimaces that they were extremely distasteful to him. Mr. Wallace believes their immunity from attack is owing to a "strong, pungent, semi-aromatic, or medicinal odor, which seems to pervade all the juices of their system."

Genus HELICONIUS, Latreille

The description of the subfamily applies to the genus sufficiently well to obviate the necessity of a more particular description, as there is but a single species in our fauna.

(1) =Heliconius charitonius=, Linnaeus, Plate VIII, Fig. 5, ? (The Yellow-barred Heliconian; The Zebra).

This insect is a deep black, the fore wings crossed by three bands of yellow: one near the apex; another running from the middle of the costa to the middle of the outer margin; a third running along the lower edge of the cell, and bending at an obtuse angle from the point where the first median nervule branches toward the outer angle, at its outer extremity followed by a small yellow dot. The hind wings are crossed by a somewhat broad band of yellow running from the inner margin near the base toward the outer angle, which it does not reach, and by a submarginal curved band of paler yellow spots, gradually diminishing in size from the inner margin toward the outer angle. There are also a number of small twinned whitish spots on the margin of the hind wing near the a.n.a.l angle. The body is black, marked with yellow spots and lines; on the under side both wings are touched with crimson at their base, and the hind wings have some pale pinkish markings near the outer angle.

The caterpillar feeds upon the pa.s.sion-flower. The chrysalis, which is dark brown, has the power when disturbed of emitting a creaking sound as it wriggles about, a property which is reported to be characteristic of all the insects in the genus. This b.u.t.terfly is found in the hotter portions of the Gulf States, and is rather abundant in Florida, in the region of the Indian River and on the head waters of the St. Johns. It ranges southward all over the lowlands of Mexico, Central America, and the Antilles.

SUBFAMILY NYMPHALINae (THE NYMPHS)

"Entomology extends the limits of being in new directions, so that I walk in nature with a sense of greater s.p.a.ce and freedom. It suggests, besides, that the universe is not rough-hewn, but perfect in its details. Nature will bear the closest inspection; she invites us to lay our eye level with the smallest leaf and take an insect view of its plane."--Th.o.r.eAU.

"My b.u.t.terfly-net and pocket magnifying-gla.s.s are rare companions for a walk in the country."--WILLIAM HAMILTON GIBSON, _Sharp Eyes_, p. 117.

_b.u.t.terfly._--The b.u.t.terflies of this subfamily are mainly of moderate or large size, though some of the genera contain quite small species.

The antennae are always more or less heavily clothed with scales, and are usually as long as the abdomen, and in a few cases even longer. The club is always well developed; it is usually long, but in some genera is short and stout. The palpi are short and stout, densely clothed with scales and hairs. The thorax is relatively stout, in some genera exceedingly so. The fore wings are relatively broad, the length being to the breadth in most cases in the ratio of 5 to 3, or 3 to 2, though in a few mimetic forms these wings are greatly produced, and narrow, patterning after the outline of the Heliconians and Ithomiids, which they mimic. The fore wings are in most genera produced at the apex, and more or less strongly excavated on the outer margin below the apex. The discoidal cell is usually less than half the length of the wing from base to tip. It is occasionally open, but is more generally closed at its outer extremity by discocellular veins diminishing in thickness from the upper to the lower outer angle of the cell. The costal nervure usually terminates midway between the end of the cell and the tip. The two inner subcostal nervules usually arise before the end of the cell; the outer subcostal nervules invariably arise beyond the end of the cell.

The hind wings are rounded or angulated, with the outer border scalloped or tailed; the inner border always affords a channel for the reception of the abdomen. The costal nervule invariably terminates at the external angle of this wing. The discoidal cell is frequently open, or simply closed by a slender veinlet, which it is not always easy to detect; the a.n.a.l vein is never lacking.

The fore legs are greatly reduced in the male, less so in the female.

_Egg._--The egg is either somewhat globular, or else barrel-shaped, with the sides marked with net-like elevations, or vertically ribbed (see Figs. 1, 8, 10).

_Caterpillar._--When first emerging from the egg the caterpillar is generally furnished with long hairs rising singly from wart-like elevations which are arranged either in longitudinal rows or in geometric patterns (Fig. 85). As the caterpillars pa.s.s their successive moults the hairs are transformed into branching spines or tubercles (see Plate III, Figs. 28-38).

[Ill.u.s.tration FIG. 85.--Caterpillar of _Vanessa antiopa_, just hatched.

(Greatly magnified.) (After Scudder.)]

_Chrysalis._--The chrysalis invariably hangs suspended from a b.u.t.ton of silk, and is frequently furnished, especially on the dorsal or upper surface, with a number of prominences; the head is usually bifurcate, or cleft (see Plate IV, Figs. 21, 39, etc.).

This is the largest of all the subfamilies of the b.u.t.terflies, and is widely distributed, including many of the most beautifully colored and most vigorous species which are known. There are twenty-six genera represented in our fauna, containing about one hundred and seventy species.

Genus COLaeNIS, Doubleday

_b.u.t.terfly._--b.u.t.terflies of moderately large size, the fore wings greatly produced and relatively narrow; the hind wings evenly rounded and relatively small, of bright reddish-brown color, with darker markings. The species are mimics, and in the elongation of their wings reveal the influence of the Heliconians, protected species, which abound in the regions in which the genus attains its greatest development. The median vein in the upper wing is characterized by the presence at the base of a minute, thorn-like, external projection; the second subcostal nervule is emitted beyond the cell; the cell of the hind wing is open.

The life-history of the two species found within our fauna has not as yet been carefully worked out, and aside from a knowledge of the fact that the caterpillars closely resemble in many respects the caterpillars of the two succeeding genera, being provided with branching spines on their bodies, we do not know as yet enough to give any complete account of the early stages of these insects.

[Ill.u.s.tration FIG. 86.--Neuration of the genus _Coloenis_, slightly less than natural size.]

(1) =Colaenis julia=, Fabricius, Plate VIII, Fig. 6, ? (Julia).