THE WESTERN CORN ROOTWORM. 3 
1878, Prof. Riley + again received larvee, this time from Mr. G. Pauls, 
of Eureka, Mo.,? and from these he reared adult beetles on the 14th 
of the following month. 
During the spring of 1874 the writer began to collect Coleoptera 
in the vicinity of Waterman, Dekalb County, Ill., but during this and 
the following two years obtained only a single beetle of this species. 
This single specimen, taken by the writer in the summer of 1874, was 
captured in a field of corn, and the failure to secure more individuals 
during the next two years will indicate the rarity of the insect at that 
time. Within seven or eight years, however, it had become so abun- 
dant throughout the neighborhood, and indeed on the same farm, 
then as now owned by the writer, as to render it impossible to secure 
more than a single 
full yield of corn 
without changing for 
a year to some other 
Gropa Upto that 
time corn had gen- 
erally been success- 
fully grown on the 
same ground for a 
number of consecu- 
tive years. The 
writer’s observations 
in Dekalb County re- 
flect with surprising 
accuracy the condi- 
tions that obtained 
throughout the corn- 
growing sections of 
Illinois, as shown by 
the information brought together by Dr. S. A. Forbes, then as now 
State entomologist * of Illinois. May, 1884, the writer ceased to be 
connected with Dr. Forbes’s office and became associated with the 
Division of Entomology of this department and was soon thereafter 
transferred from Illinois to La Fayette, Ind. 
The principal damage, as previously indicated, is caused by the 
larvee, and since 1882, in localities where no preventive measures 
have been used, the damage to the corn crop has been very serious. 
In 1885 Mr. Moses Fowler, of La Fayette, Ind., owner of an exten- 
sive tract of land, estimated his loss during that season through the 
ravages of the pest at $16,000, or about 15 per cent of the entire crop. 
On the basis of this estimate the loss sustained in 24 of the corn- 

Fic. 5.—Work of the western corn rootworm in roots of 
corn; at right, rootworm in situ. (Original.) 



1 American Entomologist, vol. 3, p. 247, 1880. (Note.—See ‘“‘ Roots of corn injured by 
some unknewn insect.” American Entomologist, vol. 2, p. 275, 1870.) 
2 Report of the Commissioner of Agriculture for 1878, p. 208, 1879. 
$14th Rept. State Ent. Ill., pp. 10-31, 1883. 
