REPORT OF OBSERVATIONS UPON INSECTS AFFECTING 
GRAINS. 
By F. M. WEBSTER, Special Agent. 
LETTER OF SUBMITTAL. 
La FAYETTE, IND., Decemder 14, 1889. 
Sir: I herewith transmit my annual report of observations on insects affecting 
cereal grains, made under your direction, during the current year. A more elaborate 
report, treating of the destructive grain insects of the United States, to be prepared 
jointly with yourself, is nearing completion, and the present report is submitted now, 
in order to avoid the necessity of including details in the more important work to 
follow. As usual, Iam under many obligatious for the determination of specimens 
and numberless other courtesies. 
Respectfully submitted. 
F. M. WEBSTER. 
Prof. C. V. RILEY, 
U. S. Entomologist. 
THE WHEAT STRAW WORM. 
(Isosoma tritici Riley.) 
These insects have not been observed by me in any great numbers 
since they were last treated in my reports, and the species is only men- 
tioned in order to record the occurrence of a female of the wingless 
spring form, on the 18th of July, in a field of wheat. 
THE WHEAT STEM MAGGOT. 
(Meromyza americana Fitch.) 
Since the establishment of the fact of a summer brood originating 
during the month of August, and largely, it is supposed, in volunteer 
wheat, considerable emphasis has been placed upon the destruction of 
this legitimate growth of grain. There has, however, been pretty 
good cause for believing that the insect developed also in other plants, 
and this season we have reared the adult from Blue grass, Poa pratensis, 
during the latter part of August. 
Since the discovery of the species there has been nothing placed on 
record relative to its discrimination between varieties of wheat, or 
42 
~ 
