1920] Melander — Synopiris of the Dipterous Family Psilidm 97 



middle. Halteres yellow. Wings with uniform slight yellow 

 tinge, veins pale yellow, sections of fourth vein proportioned 

 1 : 1 -.2:2, the last section only slightly curved, posterior cross- 

 vein nearly transverse, equal to the last section of fifth vein. 



Twenty specimens. Type from Boville, Idaho, June 18, 1911; 

 paratypes from same place (Melander), Troy (W. M. Mann) and 

 Vollmer (J. M. Aldrich), all in Idaho; and Hood River, Ore. 

 (F. R. Cole). 



Chyliza Fallen 



Dorsum of thorax yellow 2 



Dorsum of thorax mostly black, the humeri and scutellum usually 

 red 5 



2. Pleurae more or less yellow 3 



Pleurse and pectus black, a quadrangular black prealar spot; 



abdomen black; all femora with apical black ring; palpi 

 reddish (Mex.) enthea Giglio-Tos 



3. Pleurse entirely yellow; wings hyaline (Fla.) . . .similis Johnson 

 Upper half of pleurae with black vitta; apex of wings 



clouded 4 



4. Apical cloud of wings following the margin, not widened behind, 



veins two, three and four ending in the cloud; pleurse 

 marked with only the vitta. (N. J., Pa., D. C, Kans.,* 

 Colo., La., Mex.) ( Tetradiscus pictus Bigot) . apicalis Loew 

 Apical cloud widening behind, apex of veins two, three and four 

 not clouded. (Mex.) {Tetradiscus notatus Bigot, not 

 Chyliza notata Loew) bigoti, nom. nov. 



5. Front and hind femora blue-black but brownish at base, front 



tarsi black; palpi red; wings hyaline; thorax dark green, 

 shining. (Can.) metallica Walker 



Femora black except tips, tarsi yellow; palpi black; wings 

 smoky; body black. (Ore.*) leguniinicola sp. nov. 



Femora largely yellowish, sometimes with subapical dark 

 ring 6 



6. At least hind femora with well marked subapical black or brown 



band; wings with apical clouding, second and third sections 



of costa as three to one 7 



Femora yellow, at most reddish ai)ically; wings not clouded 

 apically, second and third sections of costa of robusta pro- 

 portioned two to one 11 



