BY F. W. GODING. 27 



Type, Centrotus /lexuosus, Fabr. 



This genus differs from Sertorius only in the absence of the 

 transverse venule between the two ulnar veins, a very weak 

 character. 



Synopsis of Species, 



1 (2). Third apical cell straight, first discoidal cell long, nar- 



row, two-thirds length of second; lateral horns turned 



outward, downward and backward; size large. occidentalism 



2 (1). Third apical cell crescentiform, base curved toward 



interior angle; first discoidal cell triangular, small; 



lateral horns very short and minute; size very small, minutus. 



*C. OCCIDENTALIS, Sp.nOV. 



Ferruginous, the head, base of prothorax excepting the edge, 

 tips of lateral horns, chest, abdomen, femora excepting the tips, 

 a spot on the tibiae, and tips of tarsi, black. 



Head as long as broad, base strongly curved, the apex produced 

 downward, toothed on lateral borders, punctured; ocelli white, 

 placed above a line passing centre of eyes to which they approach 

 nearer than to each other. 



Prothorax punctured, furnished with a percurrent median 

 carina ; dorsum convex, armed on each side, above lateral 

 angles, with a short, flat, conical horn, compressed infero- 

 superiorly, turned directly outward, apex obtuse, inclined a little 

 downward and backward, the upper surface with the dorsum, 

 convex; posterior process stout at the base, not tectiform, sin- 

 uous along inferior border, and gradually acuminate to the apex 

 which reaches the tips of the tegmina. 



Tegmina vitreous, clear, veins ferruginous, punctured at base, 

 a blackish cloud near base of clavus; first discoidal cell two- 

 thirds length of second, equal to and lying alongside of first 

 apical cell. 



Long. 6|; lat. 2^; inch lat. corn. 4 mm. 



9 Differs from the male in being tawny yellow, and ferruginous 

 where the male is marked with black, and the larger size. 



Long. 9; lat. 3 J; inch lat. corn. 5 mm. 



