Part 8

GENUS EUPTOIETA DOUBLEDAY

There are two species of this genus found in the United States. The butterfly has the cell of the fore wing closed by a feeble veinlet and the cell of the hind wing open. The antennæ and palpi resemble those of the genus Argynnis. The under sides of the wings are not spotted with silvery marks.

(1) Euptoieta claudia (Cramer), The Variegated Fritillary. Plate VII, Fig. 1, ♂; Fig. 2, under side.

The caterpillar feeds upon the leaves of Passion-flowers and violets. It is reddish yellow in color, with black spines on the segments, white spots on the back, and dark brown bands running the long way on the sides. The chrysalis is pearly white mottled with black spots and streaks. The insect ranges from southern New England south and west, and is reported from as far north as Alberta. It goes as far as Argentina in the south. Expanse ♂, 1.75 to 2.25 inches; ♀, 2.25 to 2.75 inches.

(2) Euptoieta hegesia (Cramer), The Mexican Fritillary.

Very much like the preceding species, only the wings, especially the hind wings, have very few dark markings, except about the borders, and the insect is smaller. Expanse ♂, 1.6 to 2.25; ♀, 2.25 to 2.5 inches.

Found in Texas, Arizona, and southward.

GENUS ARGYNNIS FABRICIUS

Butterflies of medium or large size, generally of some shade of reddish fulvous, conspicuously marked on the upper side with dark spots and waved lines, which are less conspicuously repeated on the under side, and in many species in part replaced by silvery spots. In some species the males and the females are dimorphic, that is, very different in appearance from each other. The palpi are strongly developed and clothed heavily with hairs. The antennæ have a short, well-defined, flattened, somewhat spoon-shaped club. The cells of both fore and hind wings are closed. Eggs cone-shaped, flattened, and depressed at the top, rounded at the base, ribbed both ways, mostly near the base. Caterpillars dark in color, spiny, with the spines on the first segment the longest; feeding on violets at night, and hiding during the day. Chrysalis angular, adorned with more or less prominent projections, head bifid.

This large genus has many species. It occurs in both hemispheres. Its metropolis is North America, and we can speak of only a few of the commoner and more conspicuous forms.

(1) Argynnis idalia (Drury), The Regal Fritillary. Plate VIII, ♂.

The figure given will help the student to recognize this insect. The caterpillar, when fully grown, is about 1.75 inches in length, black, banded and striped with ochreous and orange-red, and ornamented with fleshy spines, of which the two rows on the back are white tipped with black, those on the sides black tinged with orange where they spring from the body. The chrysalis is brown mottled with yellow.

Ranges from Maine to Nebraska, and southward among the Appalachian highlands into West Virginia. Expanse 2.75 to 4 inches.

(2) Argynnis diana (Cramer), Plate IX, ♂; Plate X, ♀ (Diana).

This lovely insect is dimorphic, the male having the outer borders of the wings orange-fulvous, while the female has the wings bordered with blue spots. Expanse 3.75 to 4.5 inches.

It belongs to the southern Appalachian region, and ranges from West Virginia and the Carolinas to northern Georgia, thence westward to the Ozarks, being found sparingly in southern Ohio and Indiana, and commonly in parts of Kentucky.

(3) Argynnis leto Edwards, Plate XI, ♀ (Leto).

The male of this species is in some respects not unlike the two following species, but with the wings darker at their bases; the female, on the other hand, is quite different, the dark spots on the inner half of the wings running together and giving this part of the wings a dark brown or black appearance, while the outer borders are pale yellow. Expanse 2.5 to 3.25 inches.

This beautiful form occurs on the western side of the Rocky Mountains, in California and Oregon.

(4) Argynnis cybele (Fabricius), Plate XII, ♀, under side (The Great Spangled Fritillary).

The male is bright reddish-fulvous on the upper side of the wings, with the characteristic dark markings of the genus; on the under side the wings are heavily silvered. There always is a pale yellowish submarginal band shown on the under side of the hind wings which does not appear in the next species, and by the presence or absence of which they may be discriminated from each other. The caterpillars hibernate as soon as hatched, and pass the winter in this state, feeding up and maturing in the following spring when the violets begin to grow. Expanse 3 to 4 inches.

This species ranges from Maine to Nebraska and southward to Georgia and Arkansas. It is our commonest species in the Middle States.

(5) Argynnis aphrodite (Fabricius). Plate XIII, ♀, under side (Aphrodite).

Closely resembling the preceding species, but smaller. The under side of the hind wings has the submarginal band narrower than in A. cybele and often wholly wanting, as shown in the figure. The fore wings on the under side are redder at the base than in A. cybele. Expanse 3 to 3.5 inches.

The range is the same as that of the preceding species.

The two species A. cybele and A. aphrodite usually are found flying at the same time and in the same places, and when on the wing it is often very difficult to distinguish them from each other. In fact they seem to intergrade into each other, and in a long series of specimens such close resemblances often occur that it is puzzling to decide which is which. The deeper red of the fore wing of A. cybele is the best diacritical character. The paler outer margin of the hind wing of A. aphrodite, which is typically shown in Plate XII, sometimes occurs also in A. cybele, and I have specimens of the latter which very closely approximate the former in this regard. In selecting specimens for illustration I have chosen the two extreme forms in which the pale wing of A. aphrodite is seen to contrast on the under side with the darker wing of A. cybele shown on Plate XIII.

It may be remarked in passing that the genus Argynnis is very difficult, and the writer has been in the habit of comparing it to the genus Salix, the willows, among flowers. Botanists know how the willows seem to run together, and how hard it is to discriminate the species. The same thing is true of this great genus of butterflies with which we are now dealing. It is particularly true of the species which occur in the region of the Rocky Mountains, of which the writer has probably the largest collection in existence, including all of the types of the late William H. Edwards. The test of breeding has not been fully applied as yet to all of these forms, and it is doubtful whether some of them are more than varieties or local races. There is here a field of inquiry which should tempt some young, ardent, and careful student. The day for more thorough work is at hand, and I hope some reader of these pages may be converted to the task. Entomological study should become more intensive, as well as extensive. The fathers of the science have paved the way and laid foundations; it remains for the rising generation to complete the work which the fathers have begun.

(6) Argynnis atlantis Edwards. Plate XIV, ♂ (The Mountain Silverspot).