865 
No. 145 J 
those of one of its comrades, he too stops feeding, and moves at least 
a short distance aside. When ready to cast its skin it fixes itself to 
the surface of the leaf by means of the minute sharp hooks of its 
feet j its exterior skin separates, and through a cleft at its anterior 
end the worm crawls from it, leaving the empty skin with its 
white and black tufts and pencils of hairs adhering to the leaf, 
with the legs, particularly the pair at the extremity of the body 
spread widely apart. They cast their skins three 
times in attaining their growth. The accompany- 
4 ing cut gives a view of these cast skins at each of 
ft the moultings, and shows the increase which takes 
place in the size of the caterpillar during the inter¬ 
vals. With each change of its skin a very perceptible alteration 
takes place in the appearance of the caterpillar. Its hairs, which 
at first are so fine as to be scarcely noticed by the naked eye, be¬ 
come so coarse and numerous at last as to hide from view the 
skin and the dots with which it is ornamented. 
• 
The Larva or caterpillar is sixteen fobted, cylindrical, clean clear white, with 
numerous black dots, and clothed with tufts and longer pencils of hairs, which are 
beautifully branched or bearded, and of a white color, interspersed with other tufts 
and pencils which are black, the longest of the pencils being half as long as the body. 
The accompanying figures present a dorsal and lateral 
view of the young and a dorsal view of the mature cat¬ 
erpillar, the last much contracted in its length, being 
taken from a dried cabinet specimen. On the anterior 
segments the black dots are arranged in a transverse row; 
on each of the others there are four black dots above, at 
the angles of an imaginary square, the anterior two being nearer each other, and 
upon each side is a row of three equidistant dots, the upper one larger, with three 
minute black dots slightly below it, and a short black stripe back of it. From each 
of these dots arises a tuft of white or black hairs, there being a row of eight black 
tufts along the back, the ends of which converge in the form of a steep roof, and two 
pencils of long black hairs on the fourth and also on the tenth segments. Some long 
white hairs overhang the head, which is black, smooth and shining, the bases of the 
feelers and of the jaws and upper lip being white. The neck has a large crescent- 
shaped spot above, placed transversely, and two small black dots on each sido, with 
two larger ones anteriorly below these. The legs are black, the prolegs white, with 
1 ' ar ge black spot on their outer sides. * 
The caterpillars attain their full size in about two months, and 
are then nearly an inch and a half in length. Before they are 
[Assembly, No. 145.] 
55 
