94 INSECUTOR INSCITI^ MENSTRUUS 



In the table of species (Itis. Ins. Mens., viii, 79-81, 1920), 

 this runs— 2, 5, 12, 15, 16, 19, 20, 21, 22, faUing with mutator 

 and leprincei. There is no appreciable difference in the geni- 

 talic type from that of these two species ; but the very distinct 

 coloration of the adult will make confusion unlikely. 



Culex (Isostomyia) bifoliata, new species. 



Male palpi very short; proboscis long and stout; pleurae 

 and anterior edge of mesonotum pale greenish, the dorsum ob- 

 scured by a vestiture of fine dark brown hairs, thin in spots 

 and with two narrow bare lines of whitish color ; bristles sparse 

 and long, black. Abdomen entirely black. Legs bronzy black, 

 the femora pale beneath. Wing-scales narrowly ligulate. 

 Vertex very broadly with narrow curved white scales, the erect 

 forked ones also white ; narrow ovate white scales low on the 

 sides. The white scales are intermixed sparsely with black 

 ones, especially posteriorly. 



Male hypopygium. Side-piece elliptical with tapered tip, 

 convex, a little swollen ; an area of dense stout setae on the 

 inner side, the upper hairs directed outwardly and curved. 

 Clasper long and rather slender, roundedly bent at right-angles 

 in the middle ; a membranous ridge beneath outwardly ; spine 

 thick and much widened, appendiculate ; a crest of short stout 

 minute spines on outer aspect. Outer division of lobe of side- 

 piece a single rod with four filaments at tip, one with hooked 

 tip, one smaller, the other two subequal and stout ; two crooked 

 curved leaves of moderate size, strongly inserted on the stem, 

 at basal and apical thirds respectively. Inner division of lobe 

 of side-piece a long rod, exceeding the outer division, bearing 

 two rather short stout filaments at tip, the inner more basally 

 inserted than the outer. Tenth sternites rather broad and mem- 

 branous, one margin thickened, the tip curved-comb-shaped 

 with about six teeth. Second plate of mesosome smooth, nar- 

 rowly elliptical, concave ; basal hooks curved, with broadly 

 spatulate tips. Transparent triangular plates with finger-shaped 

 ends present at the angles of side-pieces. Basal plates large, 

 emarginate. Ninth tergites undeveloped, a few setae in a 



