906 Charles Paul Alexander 



Genus Cryptolabis Osten Sacken 



1859 Cryptolabis 0. S. Proc. Acad. Nat. Sci. Phila., p. 224. 



Cryptolabis is a small but well-defined genus, including three species, 

 of which two are Nearctic and one is Neotropical. Nothing is known 

 of the immature stages, but those of C. paradoxa, at least, are probablj'^ 

 spent in moist earth. 



Cryptolabis paradoxa 0. S. 



1859 Cryptolabis paradoxa 0. S. Proc. Acad. Nat. Sci. Phila., p. 225, pi. 4, figs. 14, 

 15, 15 a. 



The species Cryptolabis paradoxa, a curious little fly, is dark brown, 

 with the dorso-pleural membranes and the root of the wings more yellowish ; 

 the whitish wings, with the apical cells pubescent and the sector short and 

 straight or even slightly convex (Plate XXXVII, 101), easily distinguish 

 the species. It is often rather common on rank herbage growing along 

 wide creeks or on river banks. In these situations it may be swept in 

 numbers from late June thruout July. 



Genus Molophilus Curtis 



1833 Molophilus Cart. Brit. Entomol., p. 444. 



The genus Molophilus includes about forty-five described species, 

 found in most parts of the world but better represented, apparently, 

 in the temperate regions of both hemispheres. The immature stages so 

 far as known are spent in moist earth. 



The local species of Molophilus may be separated according to the 

 following key: 



1. Size very small, wing about 2.5 mm.; basal deflection of R2+3 short, perpendicular, about 



as long as the radial cross- vein; basal deflection of Cui far before the fork of M. 

 [Erioptera ursina O. S. Proc. Acad. Nat. Sci. Phila., p. 228. 1859.] (Plate XXXIV, 



70.) M. ursinus (0. S.) 



Size larger, wing over 2.6 mm.; basal deflection of ^^2+3 longer, oblique; basal 

 deflection of Cu\ near the fork of M (as in M. nova-caesariensis) or beyond it on M 3+1. . . 2 



2. Wings with a brown spot on the basal deflection of Mi. [Erioptera comata Doane. Journ. 



N. Y. Ent. Soc, vol. 8, p. 188, pi. 7, fig. 20. 1900.] (Plate XXXIV, 69.) 



M. comatus (Doane) 

 Wings without such a brown spot 3 



3. Antennae of the male elongated; coloration largely yellowish 4 



Antennae short in both se.xes; coloration brown or blackish 5 



