21 
The caterpillars were beaten from the trees from June 10 to July 17; 
after that it was impossible to tind any of them. The moths began to ap- 
pear July 16-19, and continued to emerge in the breeding boxes until 
August 1. The duration of the pupa state is about one week 
It is evident that the species is single-brooded and that the caterpil- 
lar is hatched in August, and becomes nearly full grown in the early 
autumn, hibernating when nearly full-fed, since the fully grown cater- 
pillars are abundant by the first week of June. The species has been 
identified for me by Professor Fernald. It was described from Ken- 
tucky by Mr. Chambers, but the larva and food-plant have been hitherto 
unknown. 
When about to pupate it spins a small, thin, delicate cocoon, being a 
tubular ease of silk covered with bits of the scales of the spruce or fir 
buds. It is placed next to the shoot in the débris made by the larva at 
the base of the leaves. Length, 6™™; diameter, 2™™. 
DESCRIPTIVE. 
Larva.—Body cylindrical, of the usual form, reddish brown in color, and about 
6-7™™ in length. 
Pupa.—Body rather thick, of the usual pale mahogany brown color, the antenne 
and tips of the wings on the under side reaching to the middle of the fifth abdominal 
segment. End of the abdomen full and rounded, with about ten unequal, irregularly 
situated slender bristles, which are slightly curved at the end; besides these there 
are several fine bristles along the side of the body near the tip. Length, 5™™. 
Moth.—Head cream white ; antennze with the basal (second) joint white, beyond 
ringed with white and black. Palpi white, first and second joint speckled with 
black, second (longest) joint ochreous at the end; third (last) joint with two black 
rings of unequal size, the outer the longer; the tip white. Fore wings moderately 
wide, oblong ovate. Ground color ochreous whitish gray; costal region blackish, 
base black. A broad oblique band proceeds from the costal edge to the middle of the 
submedian space, ending in two white spots; there are some whitish scales on the 
outer edge of the band. Just before the middle of the wing is a broad irregular black 
band, and beyond it in the submedian space a black spot. A third broad black band 
crosses the wing, ending on the hind margin and breaking up into three black spots 
on the hind margin; the band incloses near them two twinned white dots. Near the 
outer fourth of the wing is a conspicuous white line, sharply bent outwards just be- 
hind the middle of the wing; beyond the apex of the angle of the line are several 
white scales. At the base of the fringe is an oblique line of black scales. The fringe, 
like the adjoining part of the wing, is of mixed gray ochreous, with black scales. 
Hind wings rather broad, pointed, pearly slate gray. Legs, including tarsi, banded 
with black. Expanse of wings, 13™™. 
When rubbed the green color of the fore wings becomes paler, and the three oblique 
black bands are more distinct. 
1HE KVERGREEN SPAN-WORM. 
(Thera contractata Packard.) 
A very common caterpillar on various evergreen trees, such as the 
Spruce, White Pine, Hackmatack, and the bush or common Juniper, is 
a little green one, striped with white, which is so assimilated in color to 
the glaucous green leaves with their whitish under side as to enable the 
caterpillar to escape ordinary observation. 
