608 A Cosmopolitan Butterfly. II. Its History. | October, 
midrib and curled-up rim if near the tip of the thistle leaf, or 
next the midrib or a lateral rib, if farther back; here it bites 
away the silken film and makes a nest, covering itself with a 
slight open web, into which it weaves the bitten particles of the 
film. From this retreat it sallies forth to eat irregular patches 
in the parenchyma, which it often partially covers with an exten- 
sion of the web. ; 
Each caterpillar, when it has outgrown this confined abode, 
builds for itself a separate nest, generally near the summit of a 
stalk ; it spins a thin web on the surface of the leaf, near the 
edge, if it be a broad-leaved plant, and then draws over a portion 
of the leaf by means of threads, completing the covering with a 
. silken tent ; when half grown it forsakes this and forms a more 
perfect nest, drawing together leaves, buds, and bitten fragments 
by the same process, so as to form an oval cavity, about thirty- 
five millimetres long vertically, and a little more than half as 
broad. ‘The narrow, irregular, crisped, and rather distant leaves 
of the thistle, on which it is most frequently found, cannot, how- 
ever, be made to cover even a single caterpillar, and the spaces are 
closed by a thin open web, through which the inmate can readily 
be seen, but which is sufficiently close to retain all the rejecta- 
menta of the caterpillar. The nest is usually covered, at least m 
the upper half, with spines of the plant, evidently bitten off for 
the purpose ; there is an opening in the nest, near or at the sum- 
mit, just large enough to allow the larva to emerge, apparently 
made by eating away the web. The leaves which penetrate the 
nest are not lined with silk, but the web is frequently stretched 
across the inequalities of the leaf. Within this habitation the 
larva rests with its head downward, like its congener, V. Ata- 
lanta ; but, unlike it, when its earlier stages are passed, it feeds 
upon the upper surface and parenchyma of the. leaf, without 
touching the under cuticle, and when these are consumed, it 
crawls out to seek its fortune and weave a more commodious 
mansion ; when, however, it has reached its final stage, it devours 
the entire leaf. 
When about to undergo its transformation, the caterpillar does 
not wander far, and frequently remains upon the plant which 
has nourished it. A specimen bred in confinement, but which 
had abundance of room, formed of partially dried leaves, oe 
nected by open, angular, irregular, silken meshes, averaging 
about four millimetres long, a sort of cocoon, of no definite shapes 
but larger than its previous nest, and which it attached to the top 
of the cage. 
