1921] NATURAL SCIENCES OF PHILADELPHIA. 221 



broadly concave to the narrowly bilobate apex, the area intervening 

 between these lobes forming an angle as deep as its basal width, with 

 lateral margins weakly concave. Subgenital plate scoop-shaped, 

 with marginal convexity greatest latero-caudad, distal portion 

 sharply reflexed, broad mesad, with a medio-longitudinal cleft, 

 this reflexed portion narrowing rather strongly to opposite cereal 

 bases, where it disappears. 



Head with vertex to between ocellar areas ochraceous-tawny, 

 there this area of coloration is terminated by a very fine, transverse 

 line of mummy brown, below which the face is entirely pale och- 

 raceous-buff and hkewise opaque, ^^ antennae and mouthparts 

 weakly tinged with translucent ochraceous-buff. Pronotum with 

 marginal portions transparent, faintly tinged with ochraceous-buff; 

 disk ochraceous-tawny, in some examples paling mesad to och- 

 raceous-buff tinged with ochraceous-tawny, this more extensive 

 caudad. Tegmina transparent evenly and weakly tinged with 

 ochraceous-buff. Wings transparent, with a very faint buffy 

 tinge, this becoming stronger in the area of the costal veins and 

 showing a very weak tawny suffusion about the intercalated triangle. 

 Dorsal surface of abdomen ochraceous-buff, faintly tinged with 

 ochraceous-tawny. Limbs ochraceous-buff. Ventral surface pale 

 ochraceous-buff, in the best preserved specimens showing the same 

 opaque whitish condition as found on the face. 



Measurements ( in millimeiers ). 



Length Length Width Length Width 

 of of of of of 



c? body pronotum pronotum tegmen tegmen 



Bartica, British Guiana, type 9.34 1.8 2.8 8.1 2.7 



Bartica, British Guiana, parafype 8. 1.8 2.85 8. 2.7 



9 



Bartica, British Guiana, allotype 8. 1.85 2.9 7.8 2.8 



Bartica, British Guiana, paratype 9.34 1.8 2.9 7.8 2.75 



Demerara, British Guiana, paratype 34 1.8 2 . 85 7.8 2 . 75 



Specimens Examined: 5; 2 males and 3 females. 

 Bartica, British Guiana, I, 10 to 30, 1913, (H. S. Parish), 2c^, 2 9 , 

 type, allotype and paratypes, [A. N. S. P.]. 



Demerara, British Guiana, 1901, (R. J. Crew,) 1 9 ^^^[Hebard Cln.] 



Section II. Southeastern Brazil. 



This collection is of particular interest, due to the fact that it is 



'' Specimens of the genus, in drying, apparently often lose this whitish pigmen- 

 tation, these areas in such becoming translucent weakly tinged with ochraceous- 

 buff. In such specimens, however, the areas originally more strikingly defined 

 are usually detected with little difficulty. 



^^ Abdomen squeezed out, in life probably about 8 mm. in total length. 



'^ Recorded by Rehn as Chorisoneura gracilis (Saussure), Proc. Acad. Nat. Sci. 

 Phila., 1906, p. 271, (1906). 



