SEEPHOID AND CHALCIDOID PAKASITES OF THE HESSIAN FLY 57 



Phillips and Poos, Ewytoma parva Phillips, Bi^uchophagus fune- 

 biis (Howard), Platygaster zosine Walker, Apanteles melanoscelus 

 (Katzeburg), Gephus pygmaeus Linnaeus; Coleoptera, Anthonomus 

 signatus Say. 



Host records taken from the material in the National Museum 

 collection and believed to be unpublished are : From Hemadas nubi- 

 Upennis (Ashmead) at Cherryfield, Maine; Aulacidea tumicla 

 (Bassett) at Evanston, 111., by L. H. Weld; Cephus cinctus Norton at 

 Bottineau, N.Dak., by C. N. Ainslie; Neodiprion banksiana Rohwer, 

 August 20, 1923, by S. A. Graham, locality not stated; Bruchus 

 brachialis Fahraeus, Haddon Heights, N.J., by L. J. Bottimer; 

 Coleophora pruinella Clemens, Door County, Wis., by M. H. Doner, 

 and C. salmani Heinrich, at Mount Desert Island, Maine, by A. E. 

 Brower. Two specimens are in the collection reared from galls on 

 Rubies at Ottawa, Canada. 



According to McConnell, the egg is deposited in the puparium of 

 the hessian fly but external to the enclosed host larva, and the para- 

 site larva feeds externally. The contents of the host larva are 

 completely consumed, and the parasite pupates in the fly puparium. 

 The adult emerges through a round hole which it gnaws in the pos- 

 terior end of the puparium. The egg stage under normal conditions 

 is said to last about 3 days, the larval period 8 to 12 days, and the 

 pupal period about the same length of time. The winter is passed 

 as a mature larva within the host puparium, emergence taking place 

 in late spring. Five complete generations were reared in the labor- 

 atory in a single season. Substantially the same average life cycle 

 and mode of development are recorded for the species as a parasite 

 of the jointworms (Harmolita) by Phillips and Poos. 



The species is normally a primary parasite of the hessian fly and 

 the jointworms, but it may develop also as a secondary in case other 

 parasites are present. Only a single parasite reaches maturity upon 

 one host larva, although several eggs may be deposited in the same 

 host puparium or larval cell. 



DISTRIBUTION 



In Europe Eupelmella vesicularis is evidently very widely distrib- 

 uted. Records indicate its occurrence from the British Isles and 

 western France eastward to Russia and from Sweden in the north 

 to Italy in the south. Throughout this region it seems to be a very 

 common species. 



In North America this species is likewise widely distributed. 

 Records of the Bureau of Entomology show its occurrence in the 

 following States: Maine, New Hampshire, Vermont, Massachusetts, 

 Connecticut, New York, New Jersey, Pennsylvania, Maryland, Vir- 

 ginia, Tennessee, Ohio, Indiana, Michigan, Illinois, Wisconsin, Min- 

 nesota, North Dakota, South Dakota, Nebraska, Wyoming, Colorado, 

 and Oregon. Two specimens in the National Museum collection are 

 from Ottawa, Canada, reared from galls on Rubus. Apparently the 

 species is not present in California, and to date it has not been re- 

 corded from any of the Southern States except Virginia and Ten- 

 nessee, or from the great wheat-growing sections of Iowa, Missouri, 

 Kansas, and Oklahoma. 



