The cocoon (fig. 14) is elliptical, whitish (except in the case of the winter- 

 ing pupse) , 1 mm. in length by 0.55 mm. wide, and is spun on the under- 

 side of the leaf in the protecting angles of the midveins, etc. (fig. 14). 

 In selecting a site for the cocoon the larva incloses within the pre- 

 liminary fibrils two or three mite eggs, presumably for nourishment 

 while spinning the cocoon. A larva was seen to attach a fibril deftly 

 to the dorsal bristles of an adult female that happened to wander in 

 among the guy-fibrils of the cocoon. "Staked out" in this manner 



_ the female remained 



tethered long enough 

 to deposit two eggs 

 in the precise position 

 suitable to the con- 

 venience of the spin- 

 ning larva. No effort 

 I .:;;;;-'.'^ is made, apparently, 



j to conceal the sum- 



{ ■ mer cocoons, but the 



|. overwintering co- 



£^^ coons are designed 



i with the idea of con- 



cealment. Specimens 

 of the latter type are 

 very inconspicuous, 

 owing to the fact that 

 they assume almost 

 the exact color shade 

 of the surface upon 

 which they are con- 

 structed. 



Assuming the incu- 



FiG. 14. — Cocoon of jlrZftrocnodar caroZzna on underside of violet leaf. . . , 



(Drawn by camera lucida.) (Original.) batlOU period tO be 



about 3 days (as is the 

 case with certain similar forms), with 5 days for the larval stage and 

 8 days for the pupa, the entire cycle from deposition to the issuance 

 of the adult midge wiU be approximately 16 days. We are inclined 

 to beheve that under optimum conditions the cycle may be com- 

 pleted in somewhat less time than this. Table XX presents the 

 records of predation which we have secured. 



