1871, ] 211 
well. The shape of the egg is like a conical button, being of a blunt-topped obtuse 
cone, rounded off a little towards the broad base, and a little depressed beneath , 
sometimes it is not quite regular in shape, and the top, instead of being just in the 
middle of the upper surface, is nearer one side than the other: as to its colour, 
there is generally on the rounded apex a circular whitish spot, surrounded by a 
broad ring of deep russet-brown, then comes a narrow ring of pale brown or dingy 
flesh-colour, followed by another broad one of the dark brown or russet, its lower 
edge darkest and crenulated, and the lower part of the cone, as well as the base, is 
of a pearly-whitish tint; sometimes the central spot and the zones are not so 
distinct, but the whole colouring is of a paler brown, and more diffused: the egg 
does not change colour till just before the exit of the larva, when it becomes a 
little paler; and a small hole on the upper surface, or on the side, is the only 
evidence of the larva having escaped from it. The hatching takes place generally 
from about the 15th to the 25th of April, though this year I found it begin on the 
13th and continue to the 20th. 
The newly-hatched larva is about one-eighth of an inch in length, of a very 
pale greenish-ochreous tint, covered with long, silky, curved, whitish hairs. These 
little fellows feed at first on the buds of the maple, and their delicate tint matches 
exactly that of the enveloping sheath of the bud; by the time the buds have begun 
to burst, the larvee have moulted, and are no longer so hairy looking, though some 
few hairs remain. Early in May, when the crumpled young leaves are unfolding, 
the larva has undergone a further change; it has now a naked and smooth shining 
skin, is about half-an-inch in length, and its colour is a yellowish pellucid-green, 
rather deeper on the back, the spiracular region and belly whitish-green ; the sub- 
dorsal pale yellow stripe is already conspicuous on each side of the back, and fine 
twin lines of the same colour run along the spiracular region: at this stage the 
larva takes up its characteristic position on the under-side of the leaf, where it 
reposes in a sort of curved posture, with the head bent round on one side towards 
the fifth or sixth segment of the body, on the plane of the leaf. By about the 
second or third week in May, according to the character of the season, the larva 
attains three-quarters of an inch in length: at this time the back, between the 
snb-dorsal opaque white stripes, is wholly of a bright, rather yellowish, deep green, 
semi-transparent yet velvety, while the sides and belly are of a tender opaque 
whitish-green, the twin lines as before low on the sides but now white, the tuber” 
enlar warts stand one before the other in pairs on the sub-dorsal stripes, of which 
they form a part, being also white ; the segmental folds pale yellow. Soon afte 
this period a dorsal stripe becomes visible, for the first time, and at its first ap- 
pearance is very faint, and of an obscure whitish character, as though lying deep 
below the surface; varieties also now occur that have two transverse bars of white 
on the twelfth segment, and one on the thirteenth, extending over the back from 
one sub-dorsal line to the other. 
At the end of May, or early in June, the larva attains its full-growth, which is 
. about 1¢ to 13 inches in length, the body plump and cylindrical, rather thicker 
however in the middle than at each end; the head, the lobes of which are rounded 
and full, is a little less in width than the second segment; the segmental divisions 
_are tolerably indented, and excepting on the thoracic segments there are no sub- 
dividing wrinkles on the back, though they are numerous and distinct on the sides, 
the back is therefore very smooth. 
