HOST RELATIONS OF COMPSILURA CONCINNATA 27 



Pteronidea coryla Cress., a rather uncommon species, has been re- 

 ceived at the laboratory but twice, in June and September, 1921. 

 Evidently there are two generations, individuals of the later one 

 passing the winter in their cocoons, the adults issuing the following 

 spring. The larvse are gregarious and feed in colonies on hazel nut 

 (Gorylus americana Walt.). The collections, aggregating about 100 

 larvae, gave mostly adults, there being but one parasite, Compsilura, 

 .a female fly issuing in July, 1921. 



The imported currant worm (Pteronidea ribesi Scop.) has been 

 abundantly received over a period of eight years. There are two 

 or at least a partial second generation, cocoons 18 of either generation 

 overwintering in soil. It is of very little, if any, importance as a 

 host, for Compsilura has been reared from it on only one occasion. 



COLEOPTERA 



So accustomed have we grown to the ever-increasing host list of 

 Compsilura that a new record obtained from some lepidopteron 

 causes but little comment. There have been but few collections of 

 coleopterous larvae, however, and none has ever given the parasite. 

 A rearing attended by peculiar circumstances was reported to the 

 writers by C. W. Johnson, of the Boston Society of Natural History, 

 who in 1914 recovered the parasite from the white-pine weevil (Pis- 

 sodes strobi Peck). In September of that year he was looking over 

 some of the mounted specimens of various insects in the Libby 

 Museum at Wolfboro, N. H. One mount containing a terminal shoot 

 of white pine, illustrating the work of the weevil, contained a fly 

 which seemed out of place. Upon inquiry it was found that the 

 mount had been made up as usual and that the fly must obviously 

 have issued after the mount was completed. At Johnson's request 

 the fly was given him, and he identified it as Coirvpsilura concinnata. 

 Since there was no puparium in sight, the maggot evidently pupated 

 within the burrow of the host. 



RECORDS OF COMPSILURA REARINGS OTHER THAN THOSE 

 RECORDED AT THE GIPSY MOTH LABORATORY 



The writers are indebted to D. W. Jones, of the European Corn 

 Borer Laboratory, Arlington, Mass., for the following notes on 

 Compsilura : 



Compsilura concinnata Meig. has been bred from the European corn borer 

 {Pyrausta nubilalis Hiibn.) several times during the last few years. We con- 

 sider it of little importance as a parasite of that species. 



To C. W. Johnson, the writers are indebted for the following : 



Thanaos brizo B. and L. April 19, 1920. 

 Symmerista albifrons S. and A. 



( Hearings by E. T. Learned, Fall River, Mass.) 

 Diprion simile Hartig. April 15, 1921. 



(Rearing record of M. P. Zappe, New Haven, Conn.) 



EFFECT UPON NATIVE PARASITES 



What the final outcome of the introduction of Compsilura will be 

 is for the future to decide. What has been accomplished by the 



18 The species probably hibernates as a larva within its cocoon. 



