1919.] NATURAL SCIENCES OF PHILADELPHIA. 189 



lateral apical angles of two to six white; remainder of abdomen 

 rufous. Fore and middle femora dark basally; apices of their tibiae, 

 and tarsi yellow. Hind legs except coxae rufous. Wings brownish 

 ^\ath darker borders to the veins. Proboscis as long as the black 

 antennae. Halteres black. 



Leptomydas brachyrhynchus O. S.? 



1886. Osten Sacken, Biol. Cent. Am., Dipt., i, 69. 



There are before me from the following California localities: 3cf , 

 San Diego, and Mokelumne Hill, Calaveras Co., (F. E. Blaisdell), 

 [Cal. Acad. Sci.] ; 1 9 , Barstow, San Bernardino Co., June, (J. R. 

 Haskin), [Cal. Acad. Sci.]. Although these w^ere collected from 

 widely separated localities, they seem to be conspecific. The only 

 difference in the ]Mokelumne Hill specimen is the narrow, dark, 

 bases of the abdominal segments and the slight paling in the color 

 of the apex of the antennal club. 



A brief description of the male is given below. The species is 

 based on a female from Mexico. 



cf . Wax yellow; head except middle of face, apices of third an- 

 tennal joint and entire club, mesonotum except humeri and lateral 

 margins, scutellum, more or less of pectus, metanotum, first ab- 

 dominal segment, stigmatic spot on second, spot on lateral margins 

 of all segments, and halteres, black. All pilosity yellow. Two 

 median and lateral mesonotal stripes and sometimes apex of club, 

 pale. Wings yellow. Bases of abdominal segments sometimes nar- 

 rowly black. Third antennal joint three times as long as first two 

 together, equalling the club; the latter tapering to near apex, then 

 abruptly attenuating to a rather blunt apex. Proboscis short. 

 Hind femora slightly thickened on apical half, with few flexor bristles; 

 tibiae without spurs. First posterior cell closed. Length, 17 mm. 



SYRPHID^. 



Omegasyrphus baliopterus Loew. 



1872. Microdon halioptems Loew, Berl. Ent. Zeit., xvi, 86. (Cent., x, 56.) 



Originally described from Texas. I can report the follo^ving: 

 One male from Mexico wdth the first posterior cell completely di- 

 vided by the extension of the stump from the third vein. One 

 female from Round Mountain, Texas. One female. Mill Valley, 

 California, June, (E. P. VanDuzee), [Cal. Ac. Sci.]. The last is a 

 dark specimen showing the antennae black, or, in certain angles the 

 first joint brownish; femora black with tibiae and tarsi brownish. 



