Packard.] 



i:n'sects of the forest. 



249 



two they live unobserved among the topmost shoots, antl 

 are not usually detected until half grown. Towards the end 

 of June they descend to the ground and transform to chrys- 

 alides, and in about a week after the moth appears. 



The most formidable borer of the elm tree is the three- 

 toothed Compsidea (Fig. 189, beetle and larva). It con- 

 sumes the inner bark and sometimes girdles the tree so as 

 to suddenly kill it. The female la3's her eggs in June on 

 the trunk of the tree. The worms attain maturity in the 



Fig. 189, 



Fig. 190. 



Elm Tree Borer. 



Short lined Elm Borer. 



autunni of the third year succeeding, when they may be 

 found under the bark. Another elm tree borer, but not as 

 yet known to be at all common, is the short lined Physocne- 

 mum (Fig. 190). 



Closely allied to the elm tree borer is the linden tree 

 borer (Fig. 191, Saperda vestita, Avith its larva ; a, Z>, c, dif- 

 ferent views of the head ; d, body segments, enlarged). It 

 perforates the linden tree, while the poplar is infested by 



25 



