66 INSECTS 



into its gallery, above the point of cincture, certain 

 that the next high wind will bring it safely to the ground. 

 Considering the enormous variety of species and the 

 number of points attacked, it is surprising that the 

 amount of injury caused is not much greater than it 

 is. But, aside from the natural checks, the insects 

 grow slowly in the larval stage and are rarely great 

 eaters; the borings of some of them being surprisingly 

 short, considering the size of the larva and the length 

 of time it feeds; furthermore, the twig and branch 

 borers in most cases produce only a more or less in- 

 judicious pruning, while the 

 borings in the heart wood 

 on a large tree do not neces- 

 sarily threaten its existence. 

 Still, these round-headed 

 borers may be accounted 

 among the more serious 

 enemies of woody plants. 



Fig. 26. — Bean-weevil, natural A little offshoot from the 



size and enlarged, and a much in- 1 , r 1 • 1 ,1 .1 



fested bean. plant-tecdmg beetles are the 



BruchidcB, commonly known 

 as bean- and pea-weevils because the majority of them 

 attack the seeds of plants belonging to the Leguminosce 

 or pod-bearing family. This includes not only the bean 

 and pea of the garden, but such tree forms as the locusts, 

 and almost every series has its own species of Bruchid 

 that lives and comes to maturity in the seeds. The term 

 weevil is not strictly applicable to these insects for, al- 

 though the head is very small and pointed, it is not pro- 

 duced into a snout, and the body is unusually obese, the 

 wing-covers squarely cut off behind and leaving a large 

 area of abdomen exposed posteriorly. 



Next comes a series known as the Heteromera, in 

 which the anterior and middle feet have five joints 



