18 THE CANADIAN ENTOMOLOGIST. 



Encyrtus JoJmsoni, n. sp. 



Female. — Length, 0.8 mm.; expanse, 2.1 mm. Belongs in the 

 E. mitratus group. Antennal scape cylindrical \ ovipositor scarcely 

 extruded ; wings hyaline, marginal vein lacking. Pedicel of the antenna 

 three times as long as wide, nearly cylindrical, nearly three times as long 

 as first funicle joint ; first funicle joint a little longer than wide, remaining 

 funicle joints increasing slightly in length ; entire funicle subcylindrical ; 

 club as long as four preceding funicle joints together, somewhat swollen, 

 ovate; entire flagellum slightly hairy. Body compact ; thorax somewhat 

 convex, abdomen rotund ; mesonotum with short sparse white pile ; vertex 

 moderately narrow ; ocelli forming right angle triangle ; mesonotum finely 

 transversely shagreened ; mesoscutellum finely transversely shagreened at 

 base, nearly smooth at tip ; axillae well separated at tip. General colour, 

 metallic green ; mesoscutum highly lustrous ; axillpe and base of scutellum 

 more opaque ; tip of scutellum and abdomen shining ; reflections of head 

 violaceous ; antennae dark brown, nearly black ; all legs uniformly light 

 honey-yellow. 



Male. — Closely resembles female, except in the following particulars: 

 Antennae, which are light brown in colour, have an obconical pedicel, of 

 which the breadth nearly equals the length, and which is shorter than 

 funicle joint i ; first funicle joint a little longer than second, remaining 

 joints subequal in length ; all of funicle and club with long hairs ; club 

 not widened and nearly as long as two preceding funicle joints together ; 

 abdomen broadly subtriangular. 



Type No. 1424. U. S. Nat. Mus. (Coll. Dept. Agric.) 



Described from two females, one male, reared by W. G. Johnson, 

 College Station, Md., Aug. 22, 1897, from eggs of Mtirgantia histrionica. 



NOTES AND OBSERVATIONS ON SEVERAL SPECIES OF 



DIPTERA. 



BY F. M. WEBSTER, WOOSTER, OHIO. 



Rhaviphomyia mutabilis, Loew., has several times been observed 

 preying upon Bibio pallipes. Say. I once saw hundreds of the former on 

 a picket fence that had recently been whitewashed, and all appeared 

 engaged in capturing the latter; at any rate hardly one could be found 

 that was not engaged in sucking the life out of a victim. In one case 

 the sexes were pairing while the female was lunching upon a recently 

 captured Bibio. 



