FOREST-TREE BORERS. 47 



long, narrow, and depressed in form, but abruptly widened 

 near the anterior extremity. The head is brownish, Fig 21 

 small, and sunk in the fore part of the first segment ; 

 the upper jaws are provided with three teeth, and 

 are of a black color ; and the antennaB are very 

 short. The segment which receives ^the head is 

 short and transverse ; next to it is a large oval seg- 

 ment, broader than long, and depressed or flattened 

 above and beneath. Behind this, the segments are 

 very much narrowed, and become gradually longer ; but are 

 still flattened, to the last, which is terminated by a rounded 

 tubercle or wart. There are no legs, nor any apparatus which 

 can serve as such, except two small warts on the under-side 

 of the second segment from the thorax. The motion of the 

 grub appears to be effected by the alternate contractions and 

 elongations of the segments, aided, perhaps, by the tubercu- 

 lar extremity of the body, and by its jaws, with which it takes 

 hold of the sides of its burrow, and thus draws itself along. 

 These grubs are found under the bark and in the solid wood 

 of trees, and sometimes in great numbers. They frequently 

 rest with the body bent sidewise, so that the head and tail 

 approach each other. This posture those found under bark 

 usually assume. They appear to pass several years in the 

 larva state. The pupa bears a near resemblance to the per- 

 fect insect, but is entirely white, until near the time of its last 

 transformation. Its situation is immediately under the bark, 

 the head being directed outwards, so that, when the pupa-coat 

 is cast off, the beetle has merely a thin covering of bark to 

 perforate, before making its escape from the tree. The form 

 of this perforation is oval, as is also a transverse section of the 

 burrow, that shape being best adapted to the form, motions, 

 and egress of the insect. 



Some of these beetles are known to eat leaves and flowers, 

 and of this nature is probably the food of all of them. The 

 injury they may thus commit is not very apparent, and can- 

 not bear any comparison with the extensive ravages of their 



