143 INSECTS IXJUKIOUS TO STAPLE CROPS. 



The adult beetles are from one-fourth to three-fourths of 

 an inch long, of the form shown in the illustration, and 

 are of a brown or black color, marked with darker longi- 

 tudinal ridges on the wing-covers. The larvge are of from 

 one-fourth to five-eighths of an inch long, thick fleshy 

 white grubs, with brown heads and cervical shields on first 

 segments, and footless. 



Life'liistories. — The life-histories of the different sj)ecies 

 are but partially known and vary somewhat, 



S. parvnhis hibernates over winter as a beetle, appear- 

 ing in March and April. The female punctures the stalk 

 of wheat or timothy — oats and barley are also sometimes 

 attacked — a little above the roots, and deposits her egg in 

 the cavity. This is done in May or June even up to July 

 1st. The larv^ are to be found during July, becoming 

 full-grown and pupating during the latter part of that 

 month. The larvae will eat out quite a cavity in the 

 interior of the stalk or bulb, and then attack the roots, 

 thus often killing a whole clump or stool of small grain 

 or timothy. The pupal stage is passed in a small cell in 

 the earth and lasts from two to three wrecks, adult beetles 

 emerging from the middle of August to the first of 

 October. 



The life-history of S. 7'ohustns ic not known, though 

 larvae and pupse were collected in South Carolina on 

 August 20th, and adults in early sj^ring and late August. 

 So far this species has been found only on corn. " Wher- 

 ever, ^^ says Dr. Howard, "the larva had reached its full 

 size the pith of the stalk was found completely eaten out 

 for at least five inches. Below ground even the hard, 

 external portions of the stalk were eaten through, and in 

 one instance everything except the rootlets had dis- 



