Feb. 2, I920 European Frit Fly in North America 469 



to accept the oat, usually preferring starvation, whereas they can be 

 transferred to new wheat stems with comparative ease. 



Table V. — Results of transferring larvcB of Oscinis frit from wheat stems to other wheat 



stems 



Larva 

 No. 



Result. 



181 

 182 

 183 

 184 



185 

 191 

 192 



193 

 194 



196 

 197 

 iqS 



Fed normally, and adult emerged. 



Do. 



Do. 

 Fed and developed to pupation, but pupa became moldy and adult never 



emerged. 

 Died without entering. 

 Fed normally, and adult emerged. 



Do. 

 Fed normally and developed to pupation, emergence not noted. 

 Died without entering. 



Entered stem normally but was accidentally killed later while being trans- 

 ferred to fresh stem. 

 Fed normally, and adult emerged. 

 Died without entering. 

 Fed normally, and adult emerged. 



(4) To determine whether specimens of Oscinis frit that had been 

 reared in wheat would breed in green oat kernels, a bunch of newly 

 headed oat plants was transplanted into a pan and arranged so that the 

 heads only would project up through a slot in a horizontal wide board ; an 

 8-inch glass cylinder, topped with cheesecloth, was placed over the heads, 

 and the slot in the board was filled up and chinked with cotton batting. 

 Into this cage with the oat heads 28 specimens of both sexes of the fly 

 were introduced on July 2. On the next day 4 more pairs were intro- 

 duced. None of the flies lived in this cage more than a week. On 

 August 10 a single adult emerged, the only offspring of the 36 specimens 

 confined. 



(5) To test whether Oscinis frit or any other oscinid normally lives in 

 oat kernels in the United States, it was planned to strip the green oats 

 from 50 heads (estimated to be at least 1,000 kernels) and place them in 

 a lantern-globe cage to see if any flies would emerge. The cooperation of 

 economic entomologists was obtained, and in all 79 lots of 50 heads each 

 were placed in cages. Twenty-two lots were from various places in 

 northern Indiana; 2 from Madison, Wis.; 10 from Minnesota, sent by 

 Professor Ruggles; 3 from South Dakota, sent by Mr. Severin; 7 from 

 places in Montana, sent by Messrs. Cooley, J. R. Parker, and Larrimer; 



«||l^ 4 from Washington, sent by Professor Melander; 5 from Utah, sent by 

 Professor Titus; 13 from Colorado, sent by Director Gillette; 4 from Sioux 

 City, Iowa, sent by C. N. Ainslie; and 9 lots received without data, but 

 apparently from the West. The material was in various stages, but none 

 fully ripe. It represented numerous varieties of oats, some being almost 



