J. R. MALLOCH 265 



Eyes of male not flattencil alwvc, the facets. usually slightly enlarged 

 towards the upper margin; female genitalia not as above 10 



10. Preal'ar bristle present, sometimes small, if absent the arista is plumose. 



Aricia- R.-D., pt. 

 Prealar bristle absent; arista pubescent or l)are Limnophora- R.-D,. pt. 



11. Hind co.xae with a number of hairs on j^osterior niai'gin aliove. 



Trichopticus Rondani, pt. 

 Hind coxae bare on posterior margin above 12 



12. Hind tibiae with several very long strong bristles on postero-dorsal sur- 



face; lower calypter not much larger than upper; lower supraorbital 

 bristle in female directed forward or outward and usually very long; 

 fore tarsi of I)oth sexes without long, slender, isolated sensory hairs, 

 ' the joints all with erect fine hairs ventrallj-, in the female with a number 

 of longer hairs at apex on same surface; fore tibia with one to two 

 long bristles at apex on ventral surface, which are directed ajiicad clo.se 



to ventral surface of ba.sal joint of tarsus . 13 



Hind tibia with at most a few weak l)ristles on postero-dorsal surface; 

 lower calypter very much longer than ui)per; lower supra-orbital 

 bristle in female weak, or absent, not directed forward; fore tarsi in 

 both sexes with long, fine, isolated sensory hairs. . . .Aricia R.-D., pt. 



13. Apex of proboscis stout, without recurved pointed labellae. 



Pogonomyia Pokorny 

 Apex of proboscis with a pair of pointed recurved lalx'tlae . . Drymeia R.-D , 



MYIOSPILA R.-D. 

 This genus has been considered as synonymous with Mydaea by 

 Stein who retains in the latter all species that lack the calcar on 

 the hind tibia. There are several genera lumped together ])y 

 various authors who have used that character in separating the 

 genera, and though Myiospila is more closely related to Mydaea 

 sens, str., than are some of the other groups referred to, I consider 

 it is inadvisable to sink it as synonymous with that genus until 

 we know something of the immature stages of the latter. 



Myiospila medltabunda Fabricius 



17.SI. Mtiscd inc lit'ihiurld Fabricius, S]K'c.Ins., ii, 414. 



One small male, Lagunitas Canon, Marin County, California, 

 March 29, 1908. 



- The above genera are very clo.sely related and each contains a mixture of 

 forms which reriuires further subdivision; in fa(!t the genera as at present con- 

 stituted are not natural groups. 



TH.-V-XS. AM. E.N'T. SOC, XLIV. 



