LONG HORNED BEETLES. 109 



The prion ids (Prioninae) are large, sometimes very large 

 beetles. They have the sides of the prothorax prolonged out- 

 wards into a thin, more or less toothed margin. The wing-covers 

 are usually leathery in appearance, and of a brownish or blackish 

 color. 



THE BROAD-NECKED PRIONUS. 



(Prionus laticollis Drury). 



This gigantic borer, not uncommon in our state, measures 

 in the larval stage from two and a half to three inches in length ; 

 i't is of a yellowish-white color, with a small, horny, reddish- 

 brown head, to which are fastened exceedingly dark and hard 

 jaws ; a bluish line marks the center of the back. This large grub 

 cuts a cylindrical hole a little below the surface of the ground, 

 into the roots of plants, such as the grape-vine, blackberry, oak, 

 cherry, and apple. If the root is small, barely large enough to 

 contain the larva?, nothing but a thin skin of bark is left to hide 

 the intruder. The same larva is sometimes also found in open prai- 

 ries away from other roots than those of the plants growing in 

 such places. In such cases the borer is an external feeder, but 

 it never grows to the formidable size of others feeding inside of 

 roots, and as a consequence the adult beetle of this form found 

 in prairies are much smaller, and of a very much lighter color. 

 The larva feeds for about three years, when it changes toward 

 the end of June to a pupa within the root it had occupied. Of 

 course where such borers abound the injury is great, and if a tree 

 is badly infested nothing remains but 'to dig it out and burn it. 

 Even large trees can be killed by such borers; the grape and 

 apple seem to be able to stand the injury better than other plants, 

 but they also suffer very much, even if not killed outright. In 

 berry patches infested with such insects a sudden wilting of the 

 plants in a hill, or part of a hill, indicates their presence, and 

 steps should at once be taken to find and destroy them. 



The beetles, which vary in length from less than one inch to 

 two inches, and even more, are of a pitchy-black color; in the 



