4 5 2 
The Moths and Butterflies 
cosmopolitan distribution of its food-plant, and finally and most important 
its inedibility—to birds. It secretes in its body an ill-tasting acrid fluid, 
and birds soon learn to let these disagreeable butterfly morsels alone. For 
the sake of this immunity another butterfly species, the viceroy, Basilarchia 
archippus (Pl. XI, Fig. i; also Fig. 641), which is not ill-tasting, mimics in 
extraordinary degree the color pattern of the monarch, so that it must be 
constantly mistaken for the disagreeable monarch and is passed unmolested 
by experienced birds. The monarch in the eastern states has a migratory 
habit not unlike that of birds, great swarms flying south in the autumn to the 
Gulf states and West Indies, returning north again in the spring, not in swarms, 
however, but singly. It ranges as far north as Canada. It has, too, a curious 
habit of assembling in great numbers in a few trees, like blackbirds or crows 
in a “roost,” and hanging there quietly in masses and festoons, many indi¬ 
viduals clinging only to each other and not to the branches at all. On cer¬ 
tain great pine trees near the Bay of Monterey on the Californian coast I 
have seen myriads of monarchs thus “sembled.” The eggs are laid singly 
on the leaves of various milkweed species, Asclepias cornuti the favored 
kind, and hatch in about four days. The larva (Fig. 791) attains its full 
growth in two or three weeks and is a conspicuous object with its greenish- 
white body regularly banded with narrow black and yellow stripes; it has 
two pairs of slender black filaments, one on the second thoracic and the other 
on the eighth abdominal segment. The beautiful plump chrysalid is pea- 
green, smooth, and rounded with a few black and gilt spots and bands. The 
pupal stage lasts from nine to fifteen days. There is but one generation a 
year in the north, but two appear in the south. The winter is passed by 
the adult butterfly in the warm region of the subtropics. 
Although the viceroy, Basilarchia archippus, closely resembles the 
monarch in its red-brown ground-color, black-bordered veins, and small 
white spots, only one of the half-dozen other species of the same genus is 
at all like it. This one is B. floridensis found in the southern states. The 
others have a blackish ground-color with the hind wings suffused with 
greenish blue and a few conspicuous reddish blotches on the under side 
of both wings, as in the red-spotted purple, B. astyanax , common in the East, 
or broadly banded with white, as in the banded purple, B. arthemis (PI. X, 
Fig. 6), of the northeastern states, or have a blackish-brown ground with 
broad white band and red-brown apex of the fore wings, as in Lorquins 
Admiral, B. lorquini , of the Pacific states. The larvae of Basilarchia 
feed on oaks, birches, willows, currants, and various other trees and shrubs, 
and are odd-appearing caterpillars with numerous prominent tubercles or 
bosses on the back. 
Beautiful and abundant Nymphalids are the angle-wings, tawny above 
with black markings, dead-leaf-like below and often with a little silvery 
