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120 INSECTS INJURIOUS TO FOREST AND SHADE TREES. 
a number occurring in the same tree, according to the account of Mr: 
J.S. Bailey. (Can. Ent. XI, p.1.) The eggs are laid by the long ovi- 
positor of the female in the deep crevices of the bark of the poplar. 
When hatched, 7.e., during the summer, they bore into the tree, neverappa- 
rently ceasing to eat, and extending their tunnels through solid wood, 
first in the alburnum and then through the heart, the burrows increas- 
ing in size with that of the larve, until the latter are completely grown. 
In consequence of the innumerable tunnels cut in feeding, many trees 
are destroyed. The burrows made by the larvee are about 15 millimeters 
in width, and terminate in the pupating cell, which is about 40™™ long, 
and smooth; the extremity toward the opening is closed by a wad of 
finer and then coarser filings of the wood. The coarser splinters are not 
detached entirely from the wood, but are split up by the larva all around 
the top of the cell and project like bristles. These splinters make a firm 
wad. Against them are piled a quantity of finer chips or thin filings, 
which are loose, but pressed together. 
The cell is about 40" from the outer bark of the tree, and the 
chrysalis makes its exit through the burrow by means of the teeth on 
the segments and the spinous process on the front, by which it forces 
itself by stretching and contracting the abdomen through the wood 
serapings which close the cell until it comes to the end. 
The larva is supposed to live two years, and attains maturity in Octo- 
ber, the moth issuing from the trees the following June and July, leav- 
ing the empty shell of the chrysalis sticking out of the hole. It is preyed 
upon in the larva state by an ichneumon fly. (Pailey.) It occurs near 
Albany (Bailey) and in Michigan (Kellicott). 
The larva is 45™™ long, of a pale flesh color. The first segment behind the head is 
blackish-brown above, the dark color edged with a dirty orange shading. Head ma- 
hogany brown; along the sides of the body a row of brown dots above the reddish 
stigmata, and a row of similar dots, two to a segment, on each side of the dorsal line, 
from each of which a hair arises. 
The pupa is about 30™™ lone, narrow brown-black, shining, rugose. ‘On the elypeus 
pu} Ss) ) sg, tug ) 
is a strong broad spinous process, supported at base by lateral projections. The 
abdominal segments are provided with teeth on the back, and the anal segment is 
provided with two unequal sized terminal teeth on each side of the vent. 
The moth, says Mr. Bailey, seems to belong to the genus Cossus Fabr., and not to be 
congeneric with Nyleutes robinie. The head is short, eyes naked, labial palpi small, 
oppressed, scaled. The thorax is thickly scaled, and is squarer in front than Xyleutes, 
and not so long or high. The male antenne are bipectinate ; those of the female ser- 
rated. It is allied to the European Cossus terebra, while alar ger insect. It differs from 
C. querciperda by the absence of any yellow on the male hind wings, and by its darker 
color and closer reticulations. In color it is black and gray; fore wings covered with 
black reticulations. The ground color is blackish over nearly two-thirds from the 
base of the fore wings, and outwardly gray. Beyond the cell is a transverse contin- 
uous line, broader than the rest, and outwardly bent over the median veins. Hind 
wings rounded in both sexes, with blackish hairs at base, pale and sub-pellucid, with 
short gray fringe, before which there is a narrow blackish edging. Abdomen black- 
ish. Male smaller than the females; the smallest male expanding about 40™™, the 
largest female over 60™™, (Bailey. ) 
