GRASSHOPPERS AND OTHER INJURIOUS INSECTS OF 1911 AND 1912. 73 



shoots were attacked at the surface of the soil and below. On old plants, say 

 18 inches and up, beetles were found, in rare cases, feeding a few inches above 

 the soil, and they were always found in greater numbers on the shady side 

 even on very young shoots. 



On the 11th of July, copulating was quite general all over the field but I 

 was unable to observe a single specimen deposit an egg either in the field or in 

 the insectary. 



A survey of the land ad- 

 joining the cornfield was made. 

 On the east side was a creek and 

 many trees, to the south was a 

 meadow of wild sedge and red 

 clover, on the west were weeds, 

 shrubs, trees and the Minnesota 

 river, to the north lay a small 

 strip of land that was cultivated 

 in 1911 but left untouched dur- 

 ing 1912. Some wild sedge was 

 growing here and there in the 



last named field. A few beetles Fig-. 53, side view o( S. lutwolus. Original, 



were found feeding upon the 

 sedge south and north of the field, but no larvse could be found. 



Over 150 adults were brought in to the insectary and kept in four large 

 shell vials for seven days. No copulating was observed nor any eggs to be 

 found but on July 18th, forty vials were used, four beetles in each vial. In 

 about ten minutes two adults were observed in coition. The next day several 

 pairs in coition were noticed. On July 20th, one vial contained three eggs and 

 another one egg. These eggs are small elliptical and pearly, of about 1-16 

 inches in length. They were probably all infertile for I was unable to obtain 

 any young. 



In the insectary and in the out-door cage the corn bill bug was obsexwed 

 to feed upon corn, wheat, oats, barley, timothy, foxtail, and wild sedge, but I 

 have never noticed it to feed upon any plant other than a grass or a sedge. 



As late as October 15th, larvae and adidt beetles were found. The larvae 

 in every case were found on or partly in the inside of a bulbous root of the 

 sedge, the open end of the cell being extended into the soil a short distance by 

 silken threads mixed with soil particles. From this it is very probable that 

 the corn bill bug passes the winter in two stages, one as larva in the bulbous 

 root of the sedge and second as an adult in rubbish and other sheltered places. 



Summary. 



The corn bill bug is a snout beetle and varies from five-sixteenths to six- 

 sixteenths of an inch in length, and is of a blackish color, with a few parallel 

 lines, indented with pits, running lengthwise on the back. The beetles hiber- 

 nate over winter in the advilt stage, seeking shelter under grass, rubbish, in 

 the soil and other suitable places. The larvse also probably pass the winter 

 in the bulbous root of the wild sedge, as they have been found as late as 

 October 15th, the time this article was written. 



In the spring the adults attack the wild sedges and grasses until the 

 wheat, oats, timothy and corn start to come up, when they attack the tenderer 

 and more palatable" food supply. Egg laying takes place in late spring and 

 early summer, the time varying according to the season. So far as known in 

 Minnesota, there is only a single brood in a year. 



Areas growing sedges or rushes, or any grass crop infested with the 

 pest, plowed under in the spring and planted to corn, timothy, wheat, oats 

 barley or rye is almost sure to be attacked. Since this insect attacks only 

 grass crops, so far as is known, and the adults pass the winter under grass, 

 weeds and in the soil, a preventive is suggested. Late summer or early fall 

 plowing of grass land intended for corn the following year will probably 

 destroy most of the beetles. It would be far better however to sow the field 

 to some other crop than a grass or grain crop, instead of corn, as for instance, 

 potatoes, tomatoes, beets, cucumbers, etc." 



