90 



THE BORERS OF OUR SHADE- TREES. 



tributed to the same end. It will be remembered that these 

 trees have greatly suffered, in past times, from the ravages of 

 canker-worms. Moreover, the impenetrable state of the sur- 

 face SQJI, the exhausted condition of the subsoil, and the depri- 

 vation of all benefit from the decomposition of accumulated 

 leaves, which, in a state of nature, the trees would have enjoyed, 

 but which a regard for neatness has industriously removed, have 

 doubtless had^ no small influence in diminishing the vigor of 

 the trees, and thus made them fall unresistingly a prey to insect- 

 devourers. The plan of this work precludes 

 a more full consideration of these and other 

 topics connected with the growth and decay 

 of these trees ; and I can only add, that it 

 may be prudent to cut down and burn all that 

 are much infested by the borers." 



The Three-toothed Compsidea (Fig. 101), 

 is a rather flat-bodied, dark brown beetle, 

 101. Elm Tree Beetle. with & rusty red curved line behind the eyes, 



two stripes on the thorax, and a three-toothed stripe on the outer 

 edge of each wing cover. It is about one-half an inch in length. 

 The larva (Fig. 102) is white, subcylindrical, a little flattened, 

 with the lateral fold of the body rather prominent ; the end of 

 the body is flattened, obtuse, and nearly as 

 wide at the end as at the first abdominal ring. 

 The head is one-half as wide as the prothoracic 

 ring, being rather large. The prothoracic ring, 

 or segment just behind the head, is transversely 

 oblong, being twice as broad as long ; there" is 

 a pale dorsal corneous transversely oblong 

 shield, being about two- thirds as long as wide, 

 and nearly as long as the four succeeding seg- 

 ments ; this plate is smooth, except on the pos- 

 terior half, which is rough, with the front edge 

 irregular and not extending far down the sides. 

 Fine hairs arise from the front edge and side of 

 the plate, and similar hairs are scattered over the body and 

 especially around the end. On the upper side of each segment 

 is a transversely oblong ovate roughened area, with the front 

 edge slightly convex, and the hinder slightly arcuate. On the 

 under side of each segment, are similar rough horny plates, but 

 arcuate in front, with the hinder edge straight. 



102. Elm Tree 

 Borer. 



