881) FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 
than when the eggs are first deposited. It would thus appear that 
oviposition takes place about a week later in the vicinity of Brunswick, 
Me., than in Essex County, Mass., and about a week later in north- 
ern Maine and New Hampshire than on the coast at Brunswick. 
When the larva hatches, the incision gaps open, leaving an oval hole. 
Out of this gap the larva creeps, and it rarely eats the terminal shoot, 
but crawls upon rhe leaves of the whorls next to the terminal shoot. 
At first it nibbles one side of the needle or leaf, leaving it half eateu 
and rough, serrate, and partly withered along the edge. The half- 
eaten, withered leaves of unequal length in a whorl on the end of the 
smaller branches enable one to detect the presence of the young worms 
on the tree. 
Usually after the young larvae have shed their first skin, they collect 
on the verticils of the larch and almost invariably begin to eat the 
needles, one after another, beginning at the distal end and eating the 
leaf obliquely until only a short stump is left; in this way one verticil 
after another is eaten, and when the worms are half-grown they occa- 
sionally collect around the main stem of the twig in singular clumps or 
clusters, the hinder part of the body curled over their backs, aud, owing 
to their oblique posture in reference to one another, appearing like a 
ball of worms. This singular appearance was briefly noticed by Katze- 
burg. The castings, or excrement, are long, cylindrical, more or less trun- 
cated at each end. Our saw-fly differs slightly, as has been described, 
from the German in the eggs being laid at the base of the leaves on 
the newly-grown shoots, rather than on or just under the epidermis of 
the last year's shoots, where we have repeatedly aud in vain searched 
for them. The larvse were observed to hatch out from June 20 to 30 at 
Brunswick, Me. 
The larva3 appear to attain their full size in about five to seven days 
after hatching; certainly less than or not more than ten days. There 
appear to be but three molts or changes of skiu, i. e., four stages of the 
larvae In casting the skin, the head splits open along the median line 
of the vertex, and the epicranium or sides of the head split apart on each 
side, leaving the clypeus and labrum in place ; then the body is drawn 
out of the rent, the skin adhering to the needle or leaf. 
The egg. — Slender, cylindrical, tapering rapidly towards each end. Length, 1.2 mm . 
Larva at the time of hatching.— The head very large, much wider and higher than the 
body before the latter falls out from eating; dusky or smoky green, not black, darker 
in front on the clypeus and labrum than elsewhere; eyes black; thoracic legs smoky 
green. Body uniformly pea-green: the head aud thoracic legs soon become darker, 
and the body fills out and becomes a little larger after the larva has taken food. 
Length, 3-3.5'" m . 
Larva after the first molt. — Body pale green, without the glaucous pearly bloom of 
the two later stages; head and thoracic feet black; the segments wrinkled as in the 
adult; but the short black spines of the two later stages are not to be seen. Length. 
5_7»>»\ 
Larva after the second molt.— It now has the peculiar glaucous green bloom of the 
adult on the upper part of the body, the body being pile pea-green beneath and low 
