a 
marked with black and yellowish lines and bears a double row of 
short, stout, black lines on top (fig. 121). When at rest, the larva 
holds the rear end in an elevated position, and, when handled, it 
gives off a pungent, disagreeable odor. 
Adults appear from late May to August depending on locality. 
| Eggs are laid in masses containing up to 100 eggs each on the 
| undersides of leaves. The larvae are gregarious. At first, they 
skeletonize the undersurfaces of the leaves. Later, they devour 
entire leaves, except the midrib. During their feeding, they com- 
pletely defoliate one branch before moving on to another. Mature 
larvae move to the ground and construct parchment-like cocoons 
in the duff in which to spend the winter. There is one generation 
per year. 
Populations are often heavy in unsprayed apple orchards, along 
roadsides and fence rows, and on ornamentals. In light infesta- 
tions or on ornamentals, it is often practicable to collect and 
destroy the colonies as soon as they are discovered. 
Three other eastern species of Schizura are sometimes common 
locally: the unicorn caterpillar, S. wnicornis (J. E. Smith), S. lep- 
tinoides (Grote), and S. zpomaeae Dbldy. Each species feeds on a 
wide variety of hosts, such as apple, wild cherry, elm, aspen, 
hickory, beech, paper birch, and willow. 
Gluphisia septentrionis Wlkr. occurs in southeastern Canada 
and the northern portions of eastern United States. It feeds on 
various poplars, especially trembling aspen. Full-grown larvae 
are pale green and about.37 mm. long. The head has blackish 
stripes on each side; the body is largest in the middle, and is 
marked with pinkish to reddish blotches on the back and a yellow 
| line along each side. Larvae are found from June to September, 
| and winter is spent in the pupal stage in cocoons on the ground. 
As a rule, there is one generation per year, but in some localities 
there may be two. 
F-519533 
FIGURE 120.—Dorsal and _ lateral 
views of larvae of the saddled . 
prominent, Heterocampa gutti- 
vitta. 
COURTESY CONN. AGR. EXPT. STA. 
FIGURE 121.—Larva of the red- 
humped caterpillar, Schizura 
concinna. 
317 
