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NEW AFRICAN THYBIBIDAE AND GEOMETEIDAE IN 

 THE TRING MUSEUM. 



Bv W. WARREN, M.A., F.B.S. 



Family TIIYRIDIDAE. 



Heteroschista gen. no v. 



Differs from all other genera of the family in having veins 9 and 10 of the 

 forewings long-stalked, these veins forking halfway between cell and apex. From 

 StrigUna— to which it is most nearly related, both by its stoutness of build and 

 the hairiness of the hindtibiae and abdomen of the cj— it is separated by the length 

 of the cell, which is nearly two-thirds as long as the forewings ; the snbmedian 

 vein is abruptly elbowed at one-fourth from base. In the hindwings the costal 

 vein distinctly anastomoses at a point with the subcostal just beyond the middle 

 of cell. 



Type : //. nigranalis spec. nov. 



1. Heteroschista nigranalis spec. nov. 



Forewings : deep fnlvons, covered with darker suffusion and transverse striae, 

 which form no distinct markings on the npperside ; the costal edge is marked with 

 blackish dots ; fringe concolorons. 



Uindwings : similar, but deeper fulvous. 



Underside much paler, with fewer striae ; beyond the cell is a broad dark 

 brown fascia extending from vein 6 to inner margin, distinct on the forewing, but 

 more or less obsolete ou the hindwing. Head, thorax, and abdomen above like 

 wings ; abdomen below paler ; anal tuft black. 



Expanse of wings : 26 mm. 



One S from Agberi, Niger, July 1901 (Dr. Ansorge). 



Fajuly GEOMETRIDAE. 

 Subfamily GEOMETRINAE. 

 2. Prasinocyma dohertyi spec. nov. 

 Forewings : green shagreened with whitish ; costal edge narrowly brick-red, 

 varied with black scales; cell-spot large, dull black-brown, with some rufous scales 

 about it ; marginal dots blackish, at the ends of the veins ; fringe pale green. 

 Uindwings : like forewings, except the costal edge. 



Underside pale green ; marginal dots very distinct ; costa of forewings red. 

 Face and palpi brick-red, paler below ; antennae red ; patagia green ; vertex and 

 shoulders paler green, perhaps faded ; abdomen ochreous, with a green tinge. 

 Expanse of wings : 38 mm. 



Several examples from the Kikuyu Escarpment, British East Africa, January 

 1901, 6500—9000 ft. (Doherty). 

 A very distinct species. 



