ARGYNNIS. By Dr. Ta. Leamany. 405 
characteristics seem subject to variation, we here refrain from separating the Brenthis, but rather subordinate 
them to Argynnis as a special subgroup. 
As already mentioned above, we find in America most Argynnis in the northern part of the Continent 
which has a more or less severe winter-climate; and here it is the mountainous West which has produced 
by far the greater number of species. It is just these western species that, on account of their frequently 
very close similarity, offer great difficulties. Regarding this SrreckER writes (Catal. p. 118): “The Argynnis 
of the western mountains and Pacific slope are, besides the Colias, undoubtedly among all the day-butter- 
flies of North America the most difficult to determine, being in the most extraordinary manner subject to 
variation. Thus the species monticola Behr and zerene Bsd. which had been regarded by Botspvvat as identical, 
form such endless varieties that it seems impossible to determine to which they belong’. ScuppER who tried to 
distinguish the closely allied species by means of their sexual organs, had to give it up, finding neither these 
nor the androconia sufficiently reliable. 
The American Argynnis are butterflies of medium or large size; the colouring is generally fulvous with 
more or less distinct, black markings consisting of undulate lines and round or sagittate spots, all of which 
are as a rule somewhat feebly repeated on the under surface of the forewing. Characteristic of the under sur- 
face are the silvery spots which are, especially on the hindwings, in nearly all the species more or less di- 
stinct, although greatly subject to variation, disappearing even completely in some individuals; as a rule 
they are also found, although to a much lesser extent, on the apex of the forewings, which altogether rather 
closely agrees with the hindwings, both in colouring and markings. Also the black markings are rather variable, 
in as much as the spots and bands may replace the fulvous ground-colour to such an extent that the 
wings appear almost black. Besides such Melanisms there occur also cases of Albinism, in which the black 
markings of the upper surface appear almost whitish. 
On the whole the sexes do not differ greatly from one another, chiefly in the gg having the ground- 
colour of the upper surface more brillant and more broadly fulvous, whereas the 9? have the black markings 
heavier and the ground-colour paler. But in some species the 99 differ quite considerably from the gg 
(idalia, leto, nitocris, cybele, diana, nokomis); indeed in the latter two the typical ground-colour can not at all 
be distinguished any longer, a phenomenon which, whether justly or wrongly shall not be discussed — has 
by some authors been explained by Tertiary Mimicry. Aside from these characteristics, the gg of the true 
Argynnids may nearly always be easily told by the tertiary sexual organs consisting of long tufts of hair placed 
above the subcostal vein on the hindwing. 
Head large, eyes naked, very large and prominent; palpi distented, heavily clothed with hair, with 
the exception of the last joint which is very small and pointed. Antennae moderately ‘long, hardly measuring 
half the length of the costa, with well defined, flattened, pear-shaped clubs. Abdomen not reaching the anal 
angle. Legs strong, the middle and hind tibiae armed with spines. The wings are strong, the hindwings as 
a rule more or less denticulate. Subcostal five-branched, the third nervule always nearer the fourth than the 
second. In the $3 the second subcostal nervule coalesces with the subcostal stem for some little distance. 
The cell of. both wings is closed by a fine discocellular which on the forewing invariably joins the median 
vein beyond the origin of the second median nervule, but on the hindwing precisely at that place. The hind- 
wing has a well-defined, incurved precostal nervule. 
g Of the former stages of the American Argynnis we have but an imperfect knowledge. The eggs 
are conoidal, truncated, slightly depressed at the apex, rounded at the base; ornamented on the avlis by straight 
or slightly undulate, raised ridges connected with each other by smaller raised cross-ridges. 
The caterpillar is cylindrical, stout and short, covered at the back with 4 rows of moderately long 
fleshy spines, and with one row on each side; those on the first segment generally somewhat longer than the 
rest; the sides of the venter covered with fine tubercles. In colour they are mostly black or brown, more 
or less spotted with red or yellow. All of the American species, so far as known, feed on violets only at night, 
holding themselves concealed in day-time. They hibernate when young, sometimes even before the first moult, 
feeding up in early spring, pupating after completing 5 moults. Pupa angular, with several rows of short, 
pointed projections; thorax strongly prominent, deeply incised behind. Head occasionally armed with blunt 
horns, otherwise more rounded. 
Many species are, whereever they occur, rather common; preferring meadows bordered by woods, clea- 
rings in the forest, and grassy, flower-covered slopes. Their flight is rapid, whirring, that of some of the larger 
species floating. They visit flowers of all kinds, in preference the blossoms of thistles, Rubus, Asclepiadeae 
etc.; most of them are not difficult to capture, especially in the earlier morning hours, becoming much more 
shy in the hotter afternoon. 
