June, 1922.] Leiby: Biology OF Gnorimoschema. 93 



The writer has devoted considerable attention to the study of some 

 of these parasites, particularly the biology and development of the 

 polyembryonic parasite Copidosoma gelechice.^ Only brief references 

 will be made here to the species ^ bred. 



Eurytoma sp. (probably holtcri Riley) : An external parasite of 

 the larva whose G.gg is either placed on the host larva or deposited in 

 Ihe gall chamber and eventually coming in contact with the host. 

 Some of the parasite larvae pupate in late summer and produce adults 

 which emerge from the galls while other larvae remain naked in the 

 gall over winter and produce adults the following spring. Common at 

 Ithaca, N. Y., present in Vermont and North Carolina. 



Pleurotropis sp. : Parasite of Eurytoma sp. with a life-history sim- 

 ilar to that of its host. Five to twelve larvae commonly attack one 

 host larva. Ithaca, N. Y., and Vermont. 



Copidosoma gelechicr How. : This primary parasite deposits its 

 egg in the host egg. The host larva develops normally until just 

 before pupation when it dies. An average of around 165 individuals 

 of the parasite are developed in one larva from one parasite egg. 

 The parasites pupate in the host carcass about August 10, emerge as 

 adults nearly a month later and then escape from the gall. Common 

 at Ithaca, N. Y., Williamsville, Vermont, and fairly common in 

 North Carolina. 



CaUiephialtes notanda Cress. : Parasite develops in larva devouring 

 it so that it does not pupate. Larva pupates in the gall in elongate 

 brown cocoon made of tough silk, from which the adult emerges in 

 late summer. Very common in North Carolina, present at Ithaca, 

 N. Y. 



Scambus ptcrelas Say: Parasite larva destroys the host larva and 

 pupates naked in gall chamber. Adult emerges from gall Aug. 12-24. 

 Bred fairly common at Ithaca, N. Y. 



Phaeogcnes gclechicc Ash. : Emerges from host pupa and then from 

 gall. Common at Ithaca, N. Y. 



Campoplex dimidiatus Cress. : Adult emerges from tough brown 

 white banded cocoon spun inside gall chamber. Overwinters in cocoon 

 and adult emerges late March. Ithaca, N. Y. (rare). 



1 To be issued in December 1922 number of the Journal of Morphology. 



2 The parasites were determined by Messrs. A. B. Gahan and S. A. 

 Rowher of the U. S. Nat. Museum through the kindness of Dr. L. 0. Howard 

 and in part by the writer. 



