410 



ANIMAL BIOLOGY 



both by the adults and larvae: the former by feeding and boring 

 holes for their eggs, and the latter by injuring the developing 



Fig. 260. — Life history of the Cotton Boll Weevil, Anthonornus grand is. 

 On the right, a Cotton plant attacked by the Weevil, showing a, a dry in- 

 fested 'square'; b, a 'flared square' with punctures; c, a cotton boll sectioned 

 to show attacking Weevil and larva in its cell; g, adult female with wings 

 spread as in flight; d, adult viewed from the side; h, pupa, ventral view; e, larva. 

 (From Metcalf and Flint, after U. S. Department of Agriculture.) 



flowers so that they either fail to bloom, or produce seeds with 

 few cotton fibers. (Fig. 260.) 



While Scale-insects are so small and obscure that they are 

 only a name to all except specialists, they constitute economically 

 one of the most important groups of the insect world. Scale-insects 

 infest almost all kinds of trees and shrubs; in some cases doing 

 merely temporary damage and in others actually killing the hosts. 

 Among the myriads of species, the San Jose Scale is probably the 

 most important, and since being brought to California from China 



