freely m volunteer wheat at a date earlier than its usual breed¬ 
ing season in wheat of the regular sowings; and that the greater 
part of this midsummer generation emerge as winged flies before 
wmter and lay their eggs immediately, thus giving origin to a 
time brood which hibernates chiefly in the puparium. In some 
instances, however, they pass the winter in various degrees of; 
advancement, from the recently hatched larvm to the fully formed 
semi-pupa. In the _ experiments on which the latter statements 
aie based, the individuals of this third brood came to maturity 
. id spiing a little iater ilian those of the usual fall brood, many of 
the pupae being fully formed April 15, and the imagos commencing 
to emerge April 24. 
.Concerning the early transformation to the imago, of naked 
larvae and recent ‘‘flaxseeds'’ (puparia) found in the wheat late in 
spring—from May onwards—I have only to add here to the data 
given in the I4th Report the following item derived from our 
collections of 1886. A lot of full grown larvae with a few recent 
puparia collected from growing wheat in Lawrence county May 
15, commenced to emerge on the 28th May* and continued to ap¬ 
pear as winged flies until the 17th June. The history of the 
field in which this collection was made is peculiar and ” will be 
refened to later. It is further worthy of note that puparia ob¬ 
tained b} me fiom the wheat at Edgewood, June' 17, yielded a 
few imagos July 5. 
Most of our observations and experiments for the present yeai 
were especially directed to a determination of the dates of the 
occurrence, in volunteer wheat, of the different stages of the in- 
.sect, and to the mode of hibernation of the descendants of the 
midsummer brood. 
IN VOLUNTEER WHEAT. 
V ] 
The occurrence of the larval fly in volunteer wheat in the lat¬ 
ter part of summer or early in "fall has been already reported 
more than once by farmers, but has commonly either been dis¬ 
credited, or reckoned an occasional phenomenon, due to excep¬ 
tional conditions, lo an inquiry addressed last spring to a num¬ 
ber of observant farmers, and others of my acquaintance, I 
received several answers to the effect that the occurrence of the 
larval fly in volunteer wheat was a common event in Southern 
Illinois. 
Mr. George H. Stookey, of Freeburg, writes: “In regard to 
the fly in volunteer wheat, if the stubble is plowed early— say ini 
July— I think the flaxseeds occur late in August. I have noticeS 
that when there is volunteer wheat, if it is plowed under or pasJ 
tured off, the Hessian fly is not nearly so destructive to the fol-M 
lowing crop.” . * 
*Tbe appearance of imagos May 24. 1S87, from puparia collected at Edgewood, is to be adde 
to tne above. Ihese imagos deposited eggs at once, as stated on another page. 
