57 



THE AMERICAN FRIT-FLY. 



(0.sr/»/.s .wror Macij. Vig. 15, p. 52.) 



This species has been so interminably confused with other aUied 

 species, especiall}' with what has been going the rounds as Oscuh's 

 varahiUs Ltoevf i a s^nionym, and as frequentlj^ confused with O. car- 

 honaria as with this, that it seems ahuost impossible to saj' anything 

 about it with an}' degree of certainty that one is not really dealing 

 with something else. Chcinis soror is, nevertheless, a valid species, 

 and its larvte in all probability attack growing grain, though 1 have 

 myself rarely reared it from grain, and my proof of its destructive- 

 ness in wheat fields is unfortunatel}" not as conclusive as I wish it were. 

 The larva? certain!}' have a wide range of food plants, as I have reared 

 it from maggots in the stems of Pantcum crus-galU in Indiana during 

 September, and also from the stems of Poa prate tisU in June and from 

 wheat ill July. It has also been reared from larva» wintering in the 

 seed capsules of Ycrnonia novehoracensis May 15 in Washington, D. C. ; 

 in June and July, at Columbus, Ohio, from oat plants; from the roots 

 of cucumber, October '1^ in Maryland; and from strawberry plants in 

 Michigan. Last year I reared the flies from the stems of Eragrostis 

 minor at Url)ana, 111., in vSeptember. These definitely authenticated 

 rearings of the flies show a wide range of food plants, and the species 

 is one of the most abundant of all the Oscinids. 



CONFUSION WITH OTHER SPECIES. 



Owing to a species having been found in Illinois and Kentucky 

 attacking wheat and doubtfully determined l)y Doctor Williston as 

 O.sc/nii^ r(ir!(d)!J!s Loew, now known to be a synonym of this species, 

 and this determination having been applied elsewhere to other Oscinidse 

 attacking wheat, has led to much confusion, as where the name O. r<(ri- 

 ainis' has been applied to a form committing depredations, we can not 

 say with any degree of certainty whether the insect involved was this 

 species or O. carlxniarUi^ unless specimens actually reared from the 

 plants so attacked arc at hand. Realizing the difficulty when I l)egan 

 the preparation of this bulletin, I applied to Mr. Coquillett, of the 

 United States National Museum, for suggestions as how to best over- 

 come it and received from him an offer to determine any material 

 reared from larvi\i attacking wheat in various parts of the country. 

 Doctor Fletcher had published accounts of the ravages of Oscinis vari- 

 abilis Loew? in Canada, Dr. Otto Lugger of similar ravages of Oscinis 

 soror in Minnesota, and Professor Garman of the attacks of Oscinis 

 variahilis Loew? in Kentucky. Application was therefore made to 

 Doctor Fletcher, Professor Washburn, successor t(5 the late Doctor 

 Lugger in Minnesota, and Professor Garman, for reared material in 

 order to as far as possible place the responsibility for these depredations 



