160 
MEMOIRS OF THE KATIOXAL ACADEMY OF SCIEXOES. 
A^ariety is almost obsolete, aud tlie black line is Avanting. In Buckler's figures of tlie allied 
clietccoidcs there is only a hump, fudging by the figures, none of the British species seem 
identical with ours. InDuponchel and Giu.hi6e’8 Iconograi^hie et Ilistoire Naturelle des Chenilles 
t. ii, the larva is very well figured, but there is no horn, not even a marked lateral black line, and 
the hump is not particularly Avell developed. We have not seen other figures of the European 
caterpillar. 
Mr. Meske also wrote me in 1877 as follows: 
The imago of Xotodouia rimosa Packard stands very near to the European Xofodonia dicieva Linn6, hut the 
larvse of those two 6i»ecies are entirely dilferent. The larva of the former is very slender, liglit green, and has a 
caudal horn like a sphinx larva; it feeds on Popnlm tremuloxdes. This is the second case iii the North American 
fauna where the imago stands very near to its allied European form, while the larva is entirely diflerent. The first 
case is Acronycia occxdentaVia as compared with Acvonycta psi Liiiud. 
It is well to keep the species thus distinct to emphasize the fact that the full-fed European 
larva is more like the younger stages, haATiig lagged in its deA’elopmeut behind the American 
form. 
Egg . — ^Diameter, 1.3 mm. Low hemispherical, about one-half as high as broad. Under a 
Tolies triplet the micropyle in the center is distinctly seen, and the snow-white shell is distinctly, 
though very finely, pitted or granulated. Under a Yiuch objective, the markings are seen to 
be very peculiar, the surface not being divided into polygonal areas, but studded with microscopic 
beads, which form uear the micropyle at the apex radiating series, and lower down lines of beads 
more or less parallel with the equatorial diameter. From three to seven eggs are laid on a siugle 
leaf. Probably the moth flies from one plant to another, laying a few eggs at a time. 
FreMy-hatclied /arm, Stage I , — Described a few hours after hatching, before they began to 
feed.* Length, 3.5— 1 mm. The head is rather large, shining black, smooth, and considerably 
Avider than the body; not spherical in shape, but somewhat flattened and siibcordate or bilobed, 
as the occiput is deeply indented, A large, broad, but autero-posteriorly rather sliort, black, 
mostly smooth, prothoracic plate, with slight roughnesses near the front edge AAdiere the hairs 
take their origin; the hinder edge slightly indented on the median line. On each side of the 
plate is a lateral black piliferous wart. The second and third thoracic segments each with a pair 
of conspicuous, oval, black, flatteued, piliferous warts, and two small, round ones on each side, 
the lower one being about one-half as large as the upper. Abdominal segments 1 to G each 
Avith four dorsal, piliferous, flattened black warts, the hinder ones a little farther apart than the 
anterior ones, but yet close to the latter. On segment 7 the four corresponding warts are 
arranged in a regular trapezoid, the two anterior ones being much nearer together than the 
two hinder ones. On the eighth segment is a single central ilorsal, black, oval, moderately 
prominent wart, Avhich is twice as large as the largest on the ninth segment; it is transA’erse, 
bearing a bristle at each end, thus havdng ])lainly oidginated from what was once two separate 
warts. ■ The latter segment bears four black Avarts, arranged in a regular trapezoid. The ninth 
and tenth segments are held up Avheu the laiwa AAmlks. The anal legs are black and a little 
smaller and shorter than the middle abdominal legs. The black snranal plate is subtriangular, 
being obtusely pointed in front; the surface is rough, bearing a rough, low tubercle in front on 
Avhich are minute piliferous warts. The body is someAvhat flattened, being broader than high, 
and of a peculiar, pale glaucous or sea green, the skin being polished like porcelain. 
The bail’s under a j-ineb objective are seen to be slightly bulbous at the tip, and therefore 
glandular, but under a lower power appear to taper like ordinary setoe. In Stage II the hairs 
are also slightly bulbous, and clear at the tip. 
At the end of Stage I. — Length, 5-G mm. The body is nnicb longer than before, so that the 
tubercles are farther apart, and uoav the eighth segment has tbe dorsal Avart surrounded by an 
amber-yelloAv spot, rendering it more conspicuous, and also tbe lateral coucolorous line bas 
appeared; the same tint occurs on the base of the abdominal legs, 
(Specimens described in iiart from life, August 2.) Length at the end of the stage, just before 
exuviation, G mm. The head is moderately large, in the single larva observed not so wide as tbe 
body, as it was about to molt, the prothoracic segment being greatly swollen. (In alcoholic 
specimens the head and black piliferous tubercles of the larva in the next stage can be seen 
■through.) The head is uoav black and slightly bilobed, and 1.5 mm. wide. . 
