willow caterpillars! 565 
17. Cerura occidentalis Liutner. 
(Larva, PI. XI, fig. 7.) 
The caterpillars of this moth were found feeding on willows (Salix 
nigra) by Prof. G. H. French, at Carbondale, 111., from September 9 to 
October 5. The moths began to appear tlie following season from April 
30 to June 3. 
Larva. — Length when fully grown, 1.25 to the fork of the tail. Body slightly en- 
larged in front and somewhat compressed. In about the middle of the prothoracic 
segment is a prominent projection on each side, the body sloping from these down to 
the rather small head; there is but little sloping from the back to segment 9; 
from this there is a rapid sloping to the anal segment, this ending in the two usual 
caudal filameuts ; when withdrawn these are a little more than a quarter of an inch 
long, but may be extended to three-quarters. Clear bright green, sides spotted with 
clear purple brown, the spots round the stigmata and at the base of the thoracic and 
abdominal legs the largest. The back is marked with lilac, varying in shade, and 
arranged as follows: From the two small contiguous tubercles on the back of joint 
2 to the head is a somewhat diamond-shaped space, the broadest part at the sub- 
dorsal tubercles on the prothoracic segment. From the tubercles on this segment to 
those on the next, the lilac is bordered by bright brownish purple with a white line; 
outside of this, in the middle of this diamond, is a little green shading. From the 
tubercles on the second joint from the head to the end of the body is another parti- 
colored space, lighter than the anterior one. This gradually expands so as to in- 
clude the stigmata on segment 7, then decreases in width to the anterior part of the 
anal segment, expanding a little in the middle of this, but contracting again at its 
posterior part. The lilac of this is like the first, considerably suffused with green on 
the back, and is bordered with brownish purple and white, though the colors are a 
little lighter posteriorly. These two dorsal patches are not continuous, but are sep- 
arated on the second segment by a distinct though small patch of green. The pos- 
terior projections are mostly brownish purple, though with somewhat greenish an- 
nulations, and when extended a ring of white near the extremity. Head dark lilac. 
Previous to the last molt the tubercles on the prothoracic segment ("joint 1") were 
covered with little spines. (French, Can. Ent., xiii, p. 144.) 
18. Cerura cinerea Walker. 
This species has been found feeding on the willow by Mr. Elliot, of 
New York. 
Larva. — Pale apple green ; head brown ; second and third segment also with a 
brown triangular patch not united to the brown dorsal patch. On the second seg- 
ment are two raised rough processes, like horns, brown in color. Commencing on 
the fourth and continuing to the last segment is a brown patch, a mere point on seg- 
ment 4, spreading out diagonally on 6 and 7, narrowing on 8, a little wider on 9, 
narrowing again on 10, and wider on 11 and 12. The anal segment is furnished with 
long filaments alternately brown and green. The lateral green spaces have a number 
of rather small reddish spots, and on the dorsal brown patch are some small rough- 
ened tubercles. Length, 1.30 inches. The younger stages are of a paler color in all 
parts, without any perceptible difference in the markings. (Edwards and Elliot, 
Papilio, iii, p. 130.) 
Moth. — Forewings and thorax more ashy and dusky than in any of the other 
species ; the broad median ashy band not being so distinct as in the other species, 
since it is but little darker than on both sides of it ; the outer margin, also, instead 
of being clear white or nearly so, is of the same dull ashy hue as the median baud. 
