idalia. 
diana. 
406 ARGYNNIS. By Dr. Ta. Lenmann. 
Subgroup I: Argynnis FP. 
A. idalia Drury (85) is one of the largest and most showy of the American Argynnis. The upper 
surface of the forewings of the 3 is fulvous, marked very much as in other species of the genus: hindwings 
with the exception of the basal area almost deep black, suffused with a bluish lustre, with two rows of large 
pale spots. Whereas the $3 only have the inner, discal row pale cream-coloured, the outer marginal one 
being deep ferruginous, the 99 are at once distinguished by having on both wings also the marginal row 
creamy-white. On the under surface the forewings are pale fulvous, with a more or less complete: marginal 
row of crescents displaying a feeble brassy-yellow, resinous lustre, and with a few larger spots of lustrous 
yellow along the costa. Hindwings dark olive-coloured, with three rows of large irregular spots of a dull 
greenish-silvery colour and a smaller number of similar spots and stripes at the base. Expanse: 3,0—4,0’’. 
— Caterpillar after the last moult nearly 1,8” in length, black, with bands and stripes of ferruginous 
and orange colour, and with six rows of fleshy spines covered with black bristles, those of the two middle 
dorsal rows white with black tips, of the lateral rows black with orange base. Like all known Argynnis, it 
feeds on violets at night. — Pupa large, brown, with yellow spots and reddish wing-cases. Occurs in the 
eastern United states, from Maine to Nebrasca and Arkansas, but almost everywhere local; being during some 
years rather abundant, it becomes rather scarce in others. Especially in the Northern Highlands of New 
Jersey and in the mountainous parts of the states of New York and Pennsylvania, one often finds large numbers 
in certain openings in the woods. It flies from the end of June to the beginning of September. 
As in many Argynnidi, we sometimes observe in idalia cases of the most far-going Melanism, where 
especially the 9g have the upper surface of both wings almost completely black, even the pale macular rows 
on the hindwings being practically obsolete. In connection with this we often observe a reduction of the silvery 
markings of the underside, where either only the outer row of spots or all the rows may disappear, only a 
few spots at the inner margin and base remaining visible. idalia was by ScuDDER (Syst. Rev. 23) placed into 
a genus of its own, Speyeria, on account of the somewhat varying neuration, especially the position of the 2. 
subcostal nervule; but, as we have already pointed out in the general diagnosis, a separation of the Argyn- 
nid species by means of this characteristic is not practicable, as it would lead to the most impossible results; 
for which reason one has justly abandoned both the genus Speyeria and HtByer’s Acidalia which was by 
Moore applied also to A. hyperbius (niphe). 
A. diana Cr. (85 b) is a classical example of the most highly developed sexual Dimorphism. The gd 
have the upper surface of both wings deep black-brown, with a broad marginal border of fulvous, this border 
being on the forewings interrupted on the nervules by rays of the dark ground-colour, and enclosing on both 
wings two rows of roundish dark spots, which, diminishing in size on the hindwings, gradually disappear towards 
the anal angle. The colour of the under surface is pale buff, the forewing marked with dull black at the base 
and in the inner discal area, and spotted with pale bluish near the apex of the cell. The hindwings have the 
inner two thirds densely dusted with grey-brown, and adorned with two rows of narrow, elongate silvery 
submarginal lunules, the inner frequently obsolete at the middle; in addition a few stray silverspots near the 
base. The @ is on the upper side a rich bluish-black, somewhat darker on the forewings which in the distal half 
have 3 almost parallel rows of large bluish spots, the outer of which sometimes appears almost white. Also 
on the hindwings we find three more or less complete rows of bright blue spots, the inner almost appearing 
like a broad band, gradually tapering anally and interrupted on the nervules by rays of the ground-colour, 
each component part enclosing a circular spot of jet black; the outer, terminal, row is occasionally only 
indicated. On the under surface the 2 has the ground-colour deep grey-fuscous, somewhat darker on the 
forewings, which latter are richly marked with blue and black spots. The gorgeous rows of silvery spots found 
on the under surface of the hindwings of the $¢, reappear in the 99, and are most conspicuous on the ter- 
minal margins. Expanse: 3,4—40’. — Egg greenish-white. Larva, when young, resembles up to the 
5th moult those of A. aphrodite and cybele; thereafter it is velvety-black, grows very much larger, and the 
spines which are arranged in 6 rows, with their base orange-red, are much longer. Head dull brown. Pupa dark 
brown with short, pointed, lighter coloured tubercles on the dorsal side. — diana, among all the American Argynnis 
the largest and most magnificent, is confined to the southern portion of the Appalachian Region of North 
America; it is not scarce in the mountainous parts of Virginia and West Virginia, both Carolinas, Tennes- 
see, Kentucky and Georgia, whence it has spread westward to Ohio, Indiana, Arkansas and Missouri. It is 
extremely wary, rising at the least disturbance and disappearing above the trees. Even on very bright days 
