INSECT ENEMIES OF EASTERN FORESTS 405 
the back of the first abdominal segment is a conspicuous red hump. 
The body is armed with short, stout, black spines in a double row on 
the back and smaller ones along the sides of the body (fig. 81, C). 
This species is distributed from Canada to the Gulf of Mexico and from 
the Atlantic to the Pacific. The larvae commonly feed on apple, wild 
black cherry, elm, poplar, rose, and willow, and sometimes on other 
deciduous growths. They are often locally abundant in unsprayed 
apple orchards, along roadsides and fence rows, and on ornamentals. 
There may be one or two generations, depending on the climatic 
range, the moths emerging from May to July, and in July and 
August. The eggs are white and are deposited in masses of 100 or less 
on the under sides of the leaves. The larvae are gregarious, feeding 
from the under sides of the leaves, at first skeletonizing and later de- 
vouring all but the midrib. They completely defoliate one branch 
before migrating to another. The full-grown larva constructs a parch- 
mentlike cocoon in the duff on the ground, in which it hibernates, 
pupating in the spring. In hght infestations the most practical con- 
trol practice is to collect and destroy the colonies as soon as they are 
discovered. There should be no injury by this insect where spray 
programs are carried out. 
Schizura ipomoeae Dbldy., the unicorn caterpillar (S. wnicornis 
(A. & S.)), and S. leptinoides (Grote) feed on apple, wild cherry, 
willow, and other deciduous growths, and S. badia (Pack.) feeds on 
viburnum. ‘These species are sometimes common locally, but their 
natural control factors prevent serious outbreaks. 
Four species of Cerura are more or less common in the eastern part 
of the United States. C. borealis (Bdv.) feeds on wild cherry, and C@. 
occidentalis Lint., C. cinerea Wlkr., and C. muiltiscripta Riley feed on 
poplar and willow. The larvae have rather large broad heads, but the 
prothoracic segment of each with its pair of lateral tubercles is wider. 
The body tapers gradually to the end, the anal plate is long, and the 
anal legs are modified, forming stemapoda, which are filamental and 
extensile. The color is green and brownish or tinged with red or purp- 
lish. Exclusive of caudal appendages the larvae measures 1 to 114 
inches. The caudal appendages measure up to about 34 inch. 
The full-grown larva of Pentonia marthesia (Cram.) is nearly 2 
inches long. The head is pale green, rather large, flat in front, sub- 
conical, and with the vertex high and conical. It is pinkish on the 
sides. The prothorax has a small, double, reddish tubercle on the 
back, and the body is thickest in the middle, pale green, and marked 
by a dorsal yellowish-white stripe, and occasional pinkish spots. ‘The 
anal legs are represented by two slender filaments held outstretched, 
not quite so long as the body is thick. This species ranges from Maine 
to Florida and Texas. The larvae feed on the foliage of beech, maple, 
poplar, oak, and sycamore. The moths emerge in June and July, the 
larvae may be found from July to October, and the winter is passed as 
pupae in thin, silken cocoons spun between leaves on the ground. 
The full-grown larva of Gluphisia septentrionis Wlkr. is pale green 
and about 114 inches long. The head is rounded, green, and smooth, 
with a blackish stripe on each side. The body tapers toward each end, 
is unarmed, is marked with a yellow subdorsal line on each side, and 
on the back between the subdorsal lines is a series of pinkish to red- 
