PROC. ENT. SOC. WASH., VOL. 23, NTO. 6, JUNE, 1921 127 



second and third segments with a discal pair. Sternopleura with three bristles. 

 Middle tibiae each bearing one large and one small macrochaetae on the front 

 side near the middle. Wing with the third vein bearing two bristles at the base. 

 Length nine (9) mm. 



female. Like the male except the following differences: Two large orbitals 

 directed forward; several more large hairs below the lowest frontal. Scutellum 

 reddish yellow on apical third to half. Wing with two or three bristles at the base 

 of the third vein. Length eight (8) to ten (10) mm. 



Described from six specimens. One male labeled as follows: 

 Meyersville, Md., June 4, 1914; H254; J. A. Hyslop, Collector. 



Holotype, male, Cat. No. 24,147 United States National 

 Museum. Allotype, female, Cat. No. 24,147. 



Reared at Hagerstown, Md., from the larva of Meracantha 

 contracta Beauv. There were two other specimens in this lot of 

 material but I did not think it advisable to include them because 

 they are not fully matured. 



Five females from the National Museum Collection labeled as 

 follows: two specimens from Beltsville, Md., July 9, 1916, and 

 one specimen from Mount Vernon, Va., July 4, 1917, W. L. 

 McAtee, Collector. Two specimens from Hell Canyon, N. M., 

 7,200 feet; Manzano National Forest, 18,IX,16; C. H. T. 

 Townsend, Collector. 



This species is closely allied to P. facia/is Coq. 



All the material is in the United States National Museum 

 Collection. 



STUDIES OF ZENILLIA ROSEANAE B. & B. 

 A PARASITE OF THE EUROPEAN CORN BORER. 

 (Pyrausta nubilalis Hb.) 



BY W. R. THOMPSON, U. S. Bureau of Entomology, AND M. C. THOMPSON. 



INTRODUCTION. 



The present paper embodies a portion of the principal techni- 

 cal results obtained during the first year of work in southern 

 France on one of the European parasites of the European corn 

 borer, under the direction of the senior author of this paper, 

 acting under instructions from the Chief of the Bureau of 

 Entomology. 



This paper contains the technical information necessary for 

 the recognition of the parasite under consideration, in each of 

 the successive stages of its development and for the elaboration 

 of satisfactory methods of rearing and colonization. 



Zenillia roseanae B. & B. 



Zenillia roseanae B. & B. is a Dipterous parasite belonging to 

 the family Tachinidae. The females of this species are larvi- 



