36 NOTES ON MELANOSTOMA (dIPTERA; SYRPHIDAE) 



of the face between the eyes below greater than the distance between the 

 antennae and the mouth edge. Cheeks shining bhick, gray poHinose, white 

 pilose; profile of face almost perpendicular below antennae, receding below 

 the obtuse facial knob. Eyes red, bare. Occiput silvery pollinose, pile white 

 beneath, dark above. 



Thorax and scutellum shining bluish-black, pile light gray; at apex of scutel- 

 lum a few longer blackish hairs. Wings exceeding abdomen in length, hyaline, 

 stigma light amber. Halteres dull grayish white. Tegulae dull white, fringe 

 fulvous. Legs black, knees yellow, front and middle tibiae and tarsi testace- 

 ous; front tibiae with a row of six long and rather stout black bristles, middle 

 til)iae with four similar, but slenderer bristles; pile elsewhere on legs mostly 

 whitish; pile on the sides of the thorax white. 



First segment of the abdomen shining bronze. Second segment opaque 

 black, on each side at the margin an elongate shining spot. Third segment 

 opaque black, two narrowly interrupted rhomboidal shining bronze spots, 

 extending from the anterior margins two-thirds of the length of the segment. 

 Fourth segment similar to the preceding, but the bronze spots do not extend 

 beyond the middle of the segment and the posterior border is narrowly shining 

 bronze. Fifth segment and venter shining bronze. Hyj^opygium shining 

 black. Aljdominal pile white. 



Length, 7 to S.5 mm. 



Text-figures. A. — Melanodoina chactopoda new species; i)roIile of li(>ad of 

 female (outline). B — Mdanostoma ohacurum var. rostratuin Bigot; profile of 

 head of male (outline). C — Mdanodoum onlnrio new species; profile of head 

 of male (outline). 



This species may l)e i-ecofijiiized hy Hie hroad face which re- 

 cedes l)elow and is almost ])ej'])eiHhculur in ])r()fde, liy the hhick 

 facial stripe and by the thickened bi'istles of tlu; front tibiae. 



Described from six specimens collected in tlu^ vicinity of 

 Aihambra, California, and from two individuals reared from the 

 egg at Aihambra, 1919 and 1920. 



Female. Antennae oval, brownish black, distal joint at l)ase below .yellow- 

 ish red. Vertex shining black with black j)ile. Face with whitish punctate 

 pollen below antennae, a shining ]ila(;k median strijjc not reaching the anten- 

 nae Cheeks shining black, grayish ])()]iiiiose, while i)ilose. In i)rofile the face 



