174 NEW YORK STATE MUSEUM 



ments is ornamented apically with a rather thin, irregular row of 

 setae. The female normally has 16 subsessile antennal segments, 

 the fifth with a length about two and one-half times its diameter, 

 while the sixteenth is never reduced, and in some cases at least, 

 is evidently composed of two closely fused segments. The male 

 has 16 or 17 antennal segments, the fifth with a stem as long as 

 the basal enlargement, which latter has a length one-half greater 

 than its diameter. 



Life history. There appear to be two and possibly three genera- 

 tions annually, since Doctor Lintner states that the flies begin to 

 make their appearance the latter part of May, and larvae and adults 

 have been observed at various times during July, August and often 

 in September. It is probable that this species will breed at any 

 time when clover heads afford favorable conditions, namely, from 

 early summer until late in the fall. Professor Davis calls attention 

 to the fact that the appearance of the midges is controlled to a 

 considerable extent by weather conditions, they refusing to emerge 

 when there was a dearth of moisture. This is to be expected and 

 agrees with the behavior of the Hessian fly, Phytophaga 

 destructor Say, under similar conditions. 



The life history of this species has been worked out in Illinois 

 in some detail by Dr J. W. Folsom, an abstract of his observations 

 being given below. The insect winters as a full-grown larva or 

 pupa in the soil of clover fields or in dead clover heads. A few 

 warm days and a little rain suffice to bring the larvae to the surface 

 of the ground a few days after red clover has started its second 

 year's growth. This latter occurred at Urbana, in 1907, March 19th 

 and the orange colored larvae were found March 25th to April 4th 

 inclusive, being most numerous on March 30th and April 2d. Some 

 of these larvae make a cocoon while others do not. All contract in 

 length, the integument hardens, becomes duller in color, forming 

 a puparium within which the insect develops. Midges were taken 

 outdoors May 15th but were not common till May 23d (oviposition 

 then being in progress) and attained their maximum numbers 

 May 30th. The larvae work in the heads during June and the first 

 week in July, leaving them when full grown and entering the 

 ground to pupate. Most of the larvae desert the heads about 

 June 30th, though not a few may be found as late as July 8th. 

 Three weeks or more are required for the transformation from 

 the larva to the adult, the second generation being most abundant 

 the last week of July and the first two weeks of August, though 



