442 



U. S. NATIONAL MUSEUM BULLETIN 216 



PART 3 



Figures 245, 246. — Localities: 245 (left), Mesostenus temporalis; 246 (right), M. melanurus. 



apex infuscate to entirely fuscous; hind tibia blackish, usually brownish 

 subbasally; first and last segments of hind tarsus fuscous, the rest 

 white; wings subhy aline; abdomen fulvoferruginous, the clasper 

 fuscous. 



Female: Black. Palpi dark brown, the apical segments of maxil- 

 lary palpus paler; flagellum with a median incomplete white band 

 that covers about 4 segments; tegula dark brown, sometimes whitish 

 basally; pronotum sometunes with a small white spot at upper end of 

 epomia; subtegular ridge sometimes white; front and middle femora 

 dark brown, light brown m front, especially apically; front and middle 

 tibiae light brown, darker above; front and middle tarsi brown; hind 

 femur black or blackish brown; hind tibia black; hind tarsus dark 

 brown, its second through fourth segments sometimes paler; wings 

 subhyaline; abdomen fulvoferruginous, its first segment sometimes 

 fuscous basally. 



The original description of Mesostenus tarsatus Provancher agrees 

 with the male of this species very well, except that the face is described 

 as entirely white. In the males at hand the median part of the face 

 is black. Provancher synonymized his M. tarsatus with Trachysphyrus 

 albitarsis albitarsis, but this cannot be correct if the areolet was "tres 

 petite, caree," as he described it. 



Type: 9, La Trappe, Que., Aug. 27, 1946, J. Ouellet (Washington, 

 USNM 63827). 



Paratypes (6 6^, 129): From Iowa (Ames); Maine (Lincoln Co., 

 Machias, and Winslow); Michigan (East Lansing); Minnesota 

 (Owatonna and Ramsey Co.) ; New York (Ithaca and Niagara FaUs) ; 

 Ontario (Ottawa) ; Quebec (La Trappe and Norway Bay) ; and South 

 Dakota (Pringle). 



Dates of collection are from early to late summer, the earliest and 

 latest records being: May 29 at East Lansing, Mich.; June 13 at 



