MEMOmS OP THE NATIONAL ACADEMY OF SCIENCES. 207 
a sliiny browu, with two i)oiuts at the tail and one blunter one at the head. There are also slight 
elevations on the under part of the abdomen where tlie prolegs of the caterpillar were. 
“The mimicry of the larva when on the blackberry, either stem or leaf, is i^erfect, and the 
imitative resemblance of the moth, when at rest, to the bark of a tree is still more striking. The 
moth always rests head downward with the legs all drawn togetlier and its wings folded round 
the body, which is stretched out at an angle of about 45 degrees, tjie dull gray coloring of the 
wings with the lichen-green and flesh color giving the whole such a perfect appearance to a piece 
of rough bark that the deception is iierfect. 
“ Some of the larvm are, however, infested with Tachinids and with Ox}liio)i purgator Say.^- 
(Eiley’s unpublished notes.) 
Food plants, — Apple, plum, thorn [Craicegus)^ elm, and probably poplar (Packard), BeHila alba 
(Mrs. Diminock); ha/el {Coryliis amerieana), Friimis virginiana (Lintner); Frinos vertieillahis 
(Abbot); locust, cherry, dogwood, alder, ilex, oak (Keuteumiiller). 
(ieographiml distribution , — Common throughout the Appalachian and Austroripariau sub- 
provinces. Its western limits not yet deflned, though it inhabits Napa County, Cal., according 
to Edwards. 
Canada (Saunders); Orono, Me. (Mrs. Fernald); Brunswick, Me. (Packard); Franconia, N. IT,. 
(Mrs. Slosson, and a fresh one was captured by her in the Summit House, on Mount Washington, 
New Hampshire, at the end of July); Boston, Mass. (Harris, Shurtlefl’, Sanborn); Ehode Island 
(Clark); New York (Grote, Lintner, Dyar); Plattsburg, N. Y. (Hudson); Eacine, Wis. (Emma 
Payne) ; Manhattan, Kans. (Popenoe) ; Amherst, Mass. (jMrs. Fernald) ; Georgia (Abbot and Smith) ; 
Napa County, Cal, (U, Edwards); Canada, Kittery, Me.; New Hampshire, New York, Ohio,. 
Wisconsin (French). 
Summary of the ste2)s in the asswmjdion of the generic or adaptive^ i, e,^ xyroteetive characters of three 
species of Schiznra [S, ipomea^^ leptinoides^ and iinicornis). 
The supergeneric features of the partly elevated, uplifted anal legs and a difference in the 
size of the tubercles api»ear at tlie time of hatching. 
1. The head becomes marked much as in the adult in the second stage. 
2. The tubercles begin to be differentiated in the second stage, when the prothoracic tubercles 
are much smaller than in the first. 
3. Tlie tubercles of the first abdominal segment, originally separate, become united at the 
base in the third, and form a single high-forked tubercle in the fourth stage. 
4. The glandular hairs difler generically in the second stage from those in the first. The 
flattened glandular hairs appear in the second and disappear in the fourth stage. 
5. The V-shaped dorsal mark on the sixth and seventh abdominal segments appears at the 
end of the third stage, and is due to the coalescence of three separate, whitish yellow spots. 
G, The pea-green color of the ineso- and metathoi'acic segments apjiears at the end of the 
third stage. 
It thus appears that the mimetic colorational features, being those which especially enable the 
larva to escape observation, appear shortly before the creature is half grown, then changes 
occurring at the end of the third stage, while the movable terrifying tubercle of the first 
abdominal segment becomes developed at the same time. 
When feetlingon the edge of a leaf, the Schizuric exactly imitate a xiortionof the fresh, green, 
serrated edge of a leaf, including a sere-brown withered spot, the angular, serrate outline of the 
back corresi)onding to the serrate outline of the edge of the leaf. And as the leaves only become 
siiotted with sere-brown markings by the end of summer, so the single-brooded caterpillars do not, 
in the Northern States, develop so as to exhibit their protective coloration until late in the 
summer, i. e., by the middle and last of August. 
A feature of some significance is the large size of the prothoracic tubercles in the larva of the 
first stage of S, ipomew^ which in successive stages becomes reduced to a size no greater than 
those of the other thoracic segments. 
