44 INSECUTOR INSCITI^ MENSTRUUS 



marginal pair on second and third segments, and a vestigial 

 pair on fourth ; fifth segment with some short marginal. 

 Apical cell widely open considerably before wing tip; fourth 

 vein rounded at bend, but bent rather sharply at a right angle ; 

 no appendage at bend of fourth vein, last section bent in ; hind 

 cross vein nearer bend, sinuate, its middle in line with last 

 course of fourth. Hind scale of tegulas much elongated pos- 

 teriorly, thinly fringed with rather long hairs. Wing of male 

 with front margin bulged on second costal cell. Legs moder- 

 ately slender, the hind pair elongated ; male claws of front and 

 middle legs longer than last tarsal joint; those of hind legs 

 about as long as last tarsal joint, all strongly bent at tip. Facial 

 plate longitudinally arched, distinctly carinate, the crest of 

 median line suturelike and similar to the crests of facialia. 

 Front at vertex less than one-fifth head-width in male, epistoma 

 prominent. 



Polistiopsis mima, new species. 



Length of body 19 mm. ; of wing, over 14 mm. One male, 

 Tehuantepec ( Sumichrast ) . 



Head brown to blackish in ground color, the face and front 

 varying from silvery white to velvet brown according to lights, 

 frontalia dull brown; lunula and first two antennal joints 

 rufous to brownish yellow, third antennal joint blackish, the 

 arista concolorous with second joint; beard brassy grey. 

 Thorax and abdomen reddish brown to brownish red, the 

 pleurae and coxae thinly silvery; mesoscutum and scutellum 

 thinly silvery, the former with two linear median vittae and 

 an outer anterior blotch ill-defined. Only a faint indication 

 of silvery pollen on narrow basal margin of second and third 

 segments. Legs brownish rufous, the tarsi darker. Wings 

 deep brown on costal half from base to tip, the brown follow- 

 ing fourth vein, while fifth vein and hind cross vein are 

 bordered with yellowish ; a light space in apical and discal cells. 

 Tegulae subhyaline. 



Holotype, No. 19220, U. S. Nat. Mus. 



