THE WHITE-MARKED TUSSOCK MOTH 



269 



quently there are two black spots on each side of the thorax and 

 three on each side of the whig-cover. The larva is a footless grub 

 a little over an inch long; whitish or yellowish (Fig. 271). 



Its life history extends probably over two or three years. 

 Eggs are deposited in early summer. By burrowing under the 

 bark the grub may girdle and kill the tree. A portion of an elm 

 killed by this borer is shown in figure 272. 



Control. To protect trees not infested, apply before May 1, 

 and later repeat the application, a compound of thick whitewash 

 containing crude carbolic acid. Use one quart of 

 the acid to a pailful of whitewash. To fifty gallons of 

 this wash add six pounds of arsenate of lead. This 

 protective coat may be rendered 

 inconspicuous by the addition of 

 lamp-black, and should be applied 



FIG. 271. The elm borer, larva, pupa, and imago, enlarged. 



with a brush to the trunk of the tree and to the lower portions of 

 the branches. 



The White-marked Tussock Moth. The caterpillar of this 

 insect (Heterocampa leucostigma S. and A.) is strikingly beautiful. 

 When full grown it is one and one-half inches long, hairy, with a 

 pencil or brush of hairs like a horn on either side of its head and 

 a smaller, median tuft near the tip of the abdomen ; it has four strik- 

 ing white tussocks of hairs on the middle of the first four abdominal 

 segments. The head is red; along each side of the black stripe 

 down the middle of the back is a distinct yellow stripe (Fig. 273) . 



