368 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser 



27. Cnemodon sinuosa, new species (Figs. 19, 31, 33) 

 Habitat: Oregon! Easily recognized by the sinuous- 

 last section of the fifth vein. 



Female: Length, 5.5 mm. Face slightly rounded above, a little concave 

 below the middle; oral margin very slightly produced; entirely white pilose; 

 dust area at sides slightly produced below antennae; front black pilose, across 

 the middle and above with white pile; triangular spots small, separated from 

 the side stripes; eyes extremely short black pilose, becoming white below. An- 

 tennae black; tip of the first and the second and third joints below, yellow; 

 third joint very large, broadest just before the tip which is rounded, more 

 pointed below; arista yellow, tip darker. Thorax and scutellum slightly 

 shining greenish black, white pilose; scutellum with a well-marked apical 

 groove. Abdomen slightly shining purplish black, white pilose, the usual areas 

 with black pile; fifth segment black pilose at apex. Legs black; knees, broad 

 bases and tips of front four tibiae and first two joints of their tarsi, tip of the 

 hind basitarsi and the following joint, yellow. Wings cinereous hyaline; 

 stigma dilutely luteous. 



Holotype, female, No. 862, Mus. Calif. Acad. Sci., 

 May 25, 1918, F. R. Cole, collector. 

 Type locality, Forest Grove, Oregon. 



28. • Cnemodon pisticoides (Williston) (Figs. 54, 58) 



Pipiza pisticoides Williston, Synop. N. Am. Syrph., 

 p. 29, 1886. 



Habitat: White Mountains (Will.) ; Ontario! Mostly 

 white pilose; middle coxal process pointed; hind tro- 

 chanteral process long; third segment below carinate 

 at apex; fourth segment below not carinate or rugose at 

 base. 



Male: Length, 6 mm. Face and frons shining black, slightly greenish; 

 face slightly receding to below the middle, thence perpendicular to the oral 

 margin; sides whitish pollinose; pile whitish, some black hairs about the mouth; 

 frons swollen, black pilose; vertical triangle black pilose in front, occipital 

 cilia black, at immediate vertex white; eyes short whitish pilose. Antennae 

 black, third joint yellow at base below, sub-quadrate. Thorax and scutellum 

 shining greenish black, white pilose, middle of pleurae with reddish yellow pile; 

 scutellum with apical groove. Abdomen shining, slightly purplish black, the 

 usual areas opaque; pile white, on the usual areas shorter, black, lateral mar- 

 gins entirely white pilose. Venter of third segment carinate at apex, fourth 

 segment simple. Legs black; tips of all femora, base of hind four tibiae, 

 first three joints of front and two of middle tarsi, yellow; front tibiae piceous, 

 ends yellow. Wings hyaline; stigma luteous; last section of fifth vein straight, 

 parallel to margin of wing. 



Female: Length, 5.5 mm. Pile of venter appressed. Face receding, rather 

 long; sides narrowly whitish pollinose, produced below the antennae; spots of 

 front large, nearly round; face, vertex and a narrow stripe across below the 

 middle of the front, white pilose; elsewhere the front is black pilose. Antennae 

 black, second and third joints yellowish below; third joint short oval; arista 

 black, its base luteous. Thorax and scutellum shining greenish black, white 

 pilose; scutellum with apical groove. Abdomen shining black, pile short, white; 

 apex of all the segments, narrow anterior margins and a narrow median con- 



