THE CANADIAN ENTOMOLOGIST. 27a 



5. Middle and hind tibiai with a blackish spot behind, hind ones often 

 entirely yellow ; segment r impunctate ; face mark sometimes club- 

 shaped laterally ; flagellum darker ; tegulae unspotted ; wings more 

 fuscous Illinoiensis. 



Middle and hind tibiae yellow at base ; segment i punctate; face mark 

 ])ointed on eye margin; flagellum paler beneath ; tegulse sometimes 

 spotted ; wings hyaline Sayi. 



CoLLETES, Latreille. 



Females. 



Front cox?e with distinct hairy spines ; malar space one-fifth to one-fourth 



as long as wide ; 9-1 1 mm 8. 



Front coxfe without distinct hairy spines i. 



r. Thorax above with pubescence ochraceous, not mixed with black; 



To-i I mm 7. 



Thorax above with pubescence griseous, mixed with black 2. 



2. Ventral segment 6 bicarinate ; metathorax rounded, with triangular, 



rugose reticulated enclosure ; joint 3 longer than 4 or 5 ; malar 



space one-third as long as wide ; 9-1 1 mm compactus. 



Ventral segment 6 simple; metathorax truncate, with transverse series 

 of subquadrate pits 3. 



3. Hind metatarsus about twice as long as broad ; clypeus broadly 



sulcate ; labrum concave, striate ; joint 3 nearly = 4-5 ; spurs 



dark; malar space one-fourth as long as wide; 9-1 1 mm. . .latitarsis. 



Hind metatarsus three or four times as long as broad 4. 



4. Postscutel anteriorly with transverse series of subquadrate pits ; rather 



bare; coarsely punctured ; malar space linear; 10-12 mm. .nudus. 

 Postscutel anteriorly without transverse series of subquadrate pits. . 5. 



5. Clypeus in profile strongly convex, closely and evenly punctured ; 



joint 3 nearly = 4-5 ; malar space linear ; 9-10 mm. .brevicornis- 

 Clypeus in profile slightly convex, somewhat sulcate, puncto-striate, 6. 



6. Malar space more than one-third as long as wide ; clypeus shining, 



coarsely puncto-striate; front coxse simple ; 12-13 mm. .ineequalis. 



Malar space hardly one-third as long as wide ; clypeus opaque, finely 



puncto-striate; front coxae with blunt spines; 9-1 1 mm. .Willistonii. 



7. Clypeus opaque, finely punctured, not sulcate ; pubescence of mes- 



onotum very fine and dense ; abdomen opaque, finely punctured, 

 fasci?e very even ; nervures pale ; malar space about one-fifth as 

 long as wide speciosus. 



