XXxii, '21] KNTOMOLOCICAI. NKWS 205 



26. Fore tarsi yellow, last segment black; hind tibiae largely black, 



nitiricoxa Stein 



- Fore tarsi black 27 



27. Third antennal segment in male very broad ; abdomen in both sexes 



with an interrupted central vitta and paired spot:* on dorsnin ; ante- 

 rior mid tibial bristle much nearer to apex of tibia than is the 

 posterior one; apex of fourth wing-vein much basad of apex of 

 third ntfitH'ia Stein (tibial is Stein) 



- Third antennal segment of male narrow ; abdomen in both sexes with 



or without paired dorsal spots and without central vitta; anterior 

 bristle on mid tibia almost at same distance from apex as the 

 posterior one; apices of third and fourth veins in vertical line or 

 almost so 28 



28. Lower calyptra barely larger than upper; hind tibia with a median 



posterodorsal bristle; legs black, bases of tibiae narrowly red, 



Hoploiiastcr califurnicnsis Malloch 



- Lower calyptra at least twice as large as upper ; hind tibia without 



median posterodorsal bristle 29 



29. Large species, 3.5 to 4.5 mm. in length; tibiae entirely reddish yel- 

 low; processes of fifth abdominal sternite of male longer than their 

 basal width alticnla Malloch 



- Smaller species, not over 3.5 mm. in length ; tibiae pale at bases. . .30 



30. Frons grayish pruinescent, the interfrontalia when seen from in 



front grayish, when seen from behind less distinctly so; processes 

 of fifth abdominal sternite of male not longer than their basal 

 width fmtcrna Malloch 



- Frons not grayish pruinescent, the interfrontalia when seen from in 



front brownish, from behind velvety black. . . .tinth nicina Malloch 



My species Cocnosia cilicauda belongs to Macrocoenosia. 



Professor P. Stein has published (1920) a lar.^c paper on 

 North American Anthomyiidac in which he has described sev- 

 eral species of this genus, but I am unable to locate with cer- 

 tainty any of his valid species except niyrico.va in my key. 

 Several of the species he describes as new are synonyms ot 

 previously described species. His argenticolor is art/cntatu 

 Coquillett. [olfida is evidently inodcsta Loew, and albibasis is 

 nlvca Loew. In his notes under argenticolor he mentions a 

 variant which is fuse! front Malloch, and under pilosissivna 

 Stein he mentions another which is orcuoncnsis M-illoch. His 

 pilosissiina is my longispinosa, but I have no exact data as to 

 the publication and distribution of his paper, so cannot decide 

 which name will fall. There are one or two other synonyms 

 involved. 



