'220 New BomhyUcL'v of the Group Paraeostnus. 



forward and meeting the costa at right angle ; costa of male des- 

 titute of small points; small crossvein beyond middle of disacl 

 cell. Tibire destitute of terminal spurs, pulvilli pad-like, empodium 

 wanting. 



Amfiiicosmus ELEGANS n. sp. Male. Black. Front (except on 

 the vertex) and sides of face whitish pollinose and short sparse 

 white pilose, middle of face bare, shining black; posterior half of 

 the oral margin whitish. Antennae wholly black, the first two 

 joints spai-se white pilose. Occiput white pollinose. Thorax short 

 sparse white ])ilose, marked with two white pollinose stripes which 

 extend from the front end to a point slightl}' beyond the middle; a 

 large whitc-pollinose hximeral spot extending to the root of each 

 wing, and a smaller spot on the pleura above the hind coxae. Scu- 

 tellum, short sparse white pilose, destitute of pollen. Abdomen 

 with hind margin of the first segment white, of the second segment 

 and sides and hind margins of the third and fourth segments red- 

 dish ; pile of abdomen very short, sparse, white; venter reddish in 

 the middle, the base and apex black. Femora black, the base and 

 apex yellowish ; tibiae 3'ellowish, the apex black ; tarsi black, the 

 base more or less j^ellowish. Wings wholly hyaline. Halteres 

 w^holly white. 



Female same as the male with the following exceptions : Front 

 in the middle, and upper portion of occiput destitute of pollen; 

 lower part of front, sides of face broadh', and entire oral margin, 

 white, as is also the lower part of the occiput next the e^^es. Thorax 

 destitute of the two white pollinose stripes which occur in the male. 

 Abdomen with the second, third and fourth segments wholly red- 

 dish, the hind margins of the fourth, fifth and sixth segments nar- 

 rowly bordered with white, the end of the seventh segment broadly 

 yellow. Femora largeh^ or wholly yellow^ish. Length 4.5 to 7 ram. 

 Los Angeles county, Cal. Two males and two females, in June. 



I caught these specimens while the3^ were on the wing, hovering 

 over the ground only a few inches from it among some low herbage. 

 At the time of capturing them I supposed that they were S3'rphids 

 belonging to the genus Baccha, to which groiip of insects they bear 

 a very close superficial resemblance. 



Metacosmus n. gen. Body elongated, nearly naked, destitute 

 of flattened scales and stout bristles. Head subglobular, front in 

 profile gently convex, slightly projecting forward at base of an- 

 tenna? ; face less than one-third the length of the front, projecting 

 forward nearly on a plane with the lower portion of the latter. 

 Eyes ver3' large, quite widel3'- separated in the female. Antennae 

 equal in length to the face, second joint scarcely visible, third joint 



