INSECTS INJURIOUS TO THE FIR TREE, 206 
8. THE FIR NEEDLE INCH-WORM. 
Order LEPIDOPTERA; family PHALHNID®. 
Feeding in August on the leaves of the fir and very closely mimicing the reddish 
parily dead leaves or needles; a measuring or inch worm, with the body flattened from 
above downward and tapering at both ends, thus closely approximating the form of 
a fir leaf. Head small, narrower than the body; smooth, pale, mottled and spotted 
with reddish. Body reddish, covered with fine whitish papille; a faint blackish, 
somewhat broken narrow dorsal line; a fine pale whitish subdorsal line. Lateral line 
yellowish in partly grown caterpillars, obsolete in larger ones, becoming distinct on 
the sides of tbe not large, sharply acute supra-anal plate; two large acute spines below 
the plate. Body beneath of a peculiar glaucous greenish white, with a median reddish 
line. Thoracic and abdominal legs dull livid reddish. Length 20™™, Observed 
not unfrequently at Brunswick, Me., late in August; also found feeding at Brunswick 
on the low-bush common juniper (Juniperus communis) August 26-29, 1881. 
This is one of the most remarkable cases of mimicry yet noticed 
among those feeding on coniferous trees. Often on beating them into an 
umbrella, which I used in collecting caterpillars, have I hesitated to pick 
them up, waiting to see whether or not they were simply dead fir leaves; 
in some cases the caterpillars themselves answering the question by 
walking off at their peculiar measuring gait. 
The caterpillar changed to a chrysalis August 25, the pupa, at first 
greenish, became pale mahogany brown. Length 6™™. 
9. THE ANGULAR-HEADED, MARBLED FIR INCH- WORM. 
Order LEPIDOPTERA; family PHALENID. 
Feeding on the leaves in Maine, late in August, a veryslender inch-worm; the body 
tuberculated, blackish brown. Head angular; the vertex angulated above on each 
side. Body with five pairs of well marked small prominent tubercles; sutures between 
the segments not well marked, so that it is difficult to tell on which segment the tuber- 
cles are situated. Body wood-colored, the shade of the bark of the tree, mottled with 
black-brown, reddish. gray and gray markings. Head marbled or mottled like the 
body, with a whitish line along the top of each side, and continued along the prothor- 
acic segment, and in the form of two broken white faint lines along the sides towards 
the end of the body. Anal legs much larger than the other abdominal legs. Length 
about 20™™, 
This caterpillar is not specially mimetic, though it is probably pro- 
tected from the search of birds by its general resemblance to a dry fir 
twig. It may be recognized by its angular head, dark marbled body, 
colored like the bark of the branches on which it rests, and by the five 
pair of sharp, prominent small tubercles. It closely resembles in color- 
ation the noctuid caterpillar (No. 14) on the same tree. It may be found 
to be identical with No. 16 on the spruce. 
10. THE TEN-LINED PINE INCH-WORM. 
Feeding on the leaves of the fir, hemlock, and spruce, an inch-worm with body very 
slender, with minute prominent tubercles, and a large, full, rounded head; the latter 
deeply divided in the middle, and much wider than the body. The general color a 
flesh tint, with 8-10 blackish-brown lines on top of the body. Head reddish, mottled 
