THE CANADIAN ENTOMOLOGIST 425 



and laterals; fourth with a complete row ending ventrally in long 

 hairs. 



Genital segments. — Prominent, usually the greater part of 

 firet exposed; ground colour dull orange or yellowish; first (g. s. 1) 

 sometimes brownish, usually with pollen, sometimes partly grayish 

 pollinose and occasionally entirely so except lateral posterior por- 

 tions. First (g. s. 1), vestiture shorter than that of second, 

 "humps" almost bare, in profile with a slight depression anterior 

 to marginal bristles, latter rarely strong, usually hair-like or even 

 so weak as to be scarcely distinguishable. Membrane joining 

 first and second segments dorsally often blackish. Second (g. s. 2), 

 rotund, not flattened, anal area rather small and not extending 

 above middle of posterior surface. Forceps ( 9 ) darkened, usually 

 blackish, at least distally, hairy to beyond middle; base with up- 

 W£ rd flap-like extensions clothed with fine hair shorter than vestiture 

 of second segment; tips of prongs spread and bent forward, (a. .p — 

 ascessory plate, a. c. — anterior claspers, p. c. — posterior claspers.) 



Genitalia. — Distinctive for North American species. 



9 . — Females differ from males in the following important 

 characters. 



Head. — ^Breadth of front at narrowest part slightly less than 

 eye width. Upper inner orbits of eyes diverging downward. 



Thorax. — Vestiture of metanotum of short reclinate bristles 

 or nearly erect bristly hair except that vestiture of scutellum is 

 hairy and erect throughout, or at least anteriorly. 



Legs. — Posterior trochanter with slender apical bristle: femur 

 somewhat spindle-shaped, not arched, bristles of intermediate 

 row on anterior face restricted to proximal half and sometimes 

 only a few present; posterior row with ventral row of long, well 

 separated bristles on proximal half or slightly more. Anterior 

 and posterior ventral rows of middle femur complete, but bristles 

 weak and inconspicuous distally: submesotibial bristle very strong, 

 sometimes a short bristle just above it. 



Chcetotaxy. — -Lower sternopleura with bristles only, or at most 

 but a few long hairs anteriorly. 



Abdomen. — Oval; vestiture short throughout, clothed above 

 with reclinate bristles, beneath either with more erect hair or 

 bristles. 



