8 



amounted, in fact, to a demonstration of the preventive effect of the 

 fall plowing" of such lands. 



Sl'HENOPHOKUS PLACIDUS Say. 



This species has been several times taken on corn in Illinois, 

 but the most notable instance of its injuries to that crop was g-iv- 

 en me by Mr. Joseph Carter, of Rankin, Vermilion county. In a 

 letter dated May 1, 1887, he incloses a specimen of this beetle with 

 the statement that he found it below the surface of the ground eat- 

 ing- into a corn plant, and that where the injured leaf appears 

 above ground it is crossed by parallel rows of holes. He finds the 

 beetles, he says, on every plant on an acre or two of corn, and in a 

 letter of June 5 he adds that the beetle is destroying some five or 

 ten acres in an eighty-acre field. The corn in this field was plant- 

 ed on fall plowing after oats. The ground was dry and sandy and 

 tiled every hundred feet. Subsequently I learned that this eighty 

 lay adjacent to an old and run-down meadow of timothy with a little 

 redtop intermixed, and that the injured patch of corn was near this 

 meadow. It is to be inferred from this statement that the bill-bugs 

 had scattered out from this field of timothy to the adjacent corn in 

 search of food. 



The life history of this species is not definitely known, its im- 

 mature stages never having been distinguished so far as my infor- 

 mation goes. Our earliest collection of the beetles was made April 

 8, 1892, from overflowed land on a creek bottom near Urbana — evi- 

 dently a hibernating specimen. The next date of its occurrence is 

 May 21, 1888, in lately plowed sod near Champaign ; and the next. 

 May 31, 1887, as given above. June 1, 1895, it was found injuring 

 corn in Leroy, in McLean county ; June 5, 18H7, it was still at work 

 in the field at Rankin ; June 14, 1882, it was taken at Normal in 

 miscellaneous collections ; June 19, at Spring Valley, from young 

 corn ; June 30, 1888, from driftwood in a small creek near Urbana 

 after a flooding storm ; and July 7 of the same year, from corn at 

 Bement, 111., where it was doing considerable injury. June 19, 

 1902, it came to us from northern Illinois near Savanna ; June 20, 

 1888, from corn fields in Whiteside county ; and August 5, 1887, 

 from Fourth Lake, in northern Illinois, where it was taken from 

 bulrushes along shore. So far as our data go they indicate a life 

 history similar to that of the better-known species ; hibernation in 

 the imago ; and an early attack on corn, with probably a midsum- 

 mer breeding period of a single generation. 



