323 



Family Periscelidae 



Small flies rcsomblino- the Laiixaniida', etc. 



Face wide, more or less produced below; front with a single pair 

 of bristles; postocellars divergent; arista plumose. Wing venation com- 

 plete, the auxiliary vein short. Abdomen oval, somewhat depressed. 



Members of this family are not numerous in collections and little is 

 known about them. i\Ialloeh would retain the genera in the Sapromyzi- 

 dm and IMelander included Scutops in his revision of the Geomyzidffi. 

 The family contains seven genera, all occurring in America, PerisceUs 

 also being found in Europe. 



KEY TO GENERA 



1. Costa extending to the fourth vein 2 



Costa ending at the third vein 5 



2. Face very strongly protruding below; auxiliary vein not curved forward 



apically 3 



Face somewhat protruding below; auxiliary vein with a distinct forward 

 curve apically; oral vibrissie absent Periscelis Lcew 



3. Face evenly convex 4 



Face flattened and bare in the middle above (3, 5) Scutops Coquillett 



4. Ocellars absent Cyamops Melander 



Ocellars long and strong (24 ) Neoseutops Malloch 



5. Face most prominent below; veins strong (6, 9) Panamenia, n. g. 



Face not prominent below, more or less convex in the middle 6 



6. Head almost or quite twice as wide as high; face very wide (8, 10). 



Sphyroperiscelis Sturtevant 

 Head not nearly so wide; face and eyes of moderate width (1, 7). 



Marbenia Malloch 



Panamenia, new genus 



This genus is, perliaps, most closely related to SiyJujroiJenscelis 

 Sturtevant but the shape of the head is distinctive. The face is shield- 

 shaped, the point below, the sides sharply limited and haired. Abdomen 

 as broad as long, tai)ering sharply from near tlie base. Scutellum flat, 

 bearing two pairs of marginals. AVings as in figure. Genotype: — 

 P. chapmani, n. sp. 



Head stramineous, the upper occiput and a broad frontal triangle 

 black; thorax deep brown or l)lackish, the pleura yellowisli; humeri, a 

 large rectangle on the posterior half of the mesonotum and the scutel- 

 lum, except the sides, stramineous; legs reddish yellow, tlie tibia with 

 two brown bands, the anterior femora brown basally; wings brownish, 

 with a preapical hyaline band; abdomen blackish or dark brown. Male, 

 Barro Colorado Island, Canal Zone, (Curran). 



