INSECT PESTS OF OHIO SHADE AND FOREST TREES 227 



The pupa is found beneath the surface of the soil at a depth of 

 a few inches, is hard, dark brown, and measures a little more than 

 a half-inch in length. (See Plate XXIX, Fig. 2.) 



The adult is a heavy-bodied moth measuring nearly 2 inches 

 across its expanded wings. The general color of the fore wings is 

 buff brown, with darker lines running crosswise of them in an irreg- 

 ular manner. The hind wings are lighter in color and are not 

 marked by the cross-lines. (See Plate XXIX, Fig. 1.) 



The eggs are small and dull white and are deposited on the 

 underside of the leaves in masses of 300 or more. They are not 

 found frequently. (See Plate XXIX, Fig. 3.) 



Life history and habits. In July or early August, the moths 

 emerge from their pupal cells in the earth and fly about. Shortly 

 the eggs are deposited and in a little while the larvae hatch and 

 begin feeding in clusters. This gregarious habit is maintained dur- 

 ing the entire larval growth, except during the last few days when 

 the cluster becomes separated and the insects exhibit a tendency 

 to wander about. At certain intervals during larval growth, all the 

 caterpillars of a feeding cluster will start in unison to crawl down 

 to one of the larger branches or the trunk of the host, leaving as 

 they travel a faint, silken trail. They finally assemble in a cluster 

 lightly held together by silken threads. Frequently several hun- 

 dred caterpillars are found thus clustered together, making a mass 

 a foot or more long and half as broad. This hairy, compact mass 

 presents a very unsightly appearance and invariably reminds the 

 writer of the carcass of a dead maltese cat with its appendages 

 tucked under it, nailed to the tree. (See Plate XXIX, Fig. 4.) 

 The caterpillars remain clustered several hours, during which time 

 each one molts or sheds its skin. When the process is complete 

 they retrace their silken trail back to their feeding grounds. This 

 performance is repeated several times during the process of larval 

 growth. When disturbed the larva has the habit of suddenly ele- 

 vating both ends of the body and remaining rigid in a particularly 

 threatening attitude. 



When the larvae reach maturity they pass to the soil and after 

 burrowing down beneath the surface, transforms to the pupal stage. 

 The winter is passed in this condition. 



Whether there is more than one brood in Ohio has not been 

 definitely decided, although it is unlikely. However, the writer has 

 observed full-grown caterpillars as early as August 23 in northern 

 Ohio and as late as October 4 in southern Ohio, and it may be possi- 

 ble that two broods occur in southern Ohio. 



