1920.] NATURAL SCIENCES OF PHILADELPHIA. 25 



POLYACANTHOPUS new genus. 



This genus shows very close affinity to Xanthomantis in general 

 form and tegminal and wing structure, but differs particularly in the 

 different ocellar arrangement, weaker armament of the ventro- 

 internal margins of the cephalic femora, remarkably heavy arma- 

 ment of the cephalic tibiae and in the percurrent pronotal carina. 



The armament of the cephalic tibiae is heavier than in any species 

 of the Mantidae we have ever seen. 



Genus monotypic. Genotype. — Polyacanthopus mantispoides 

 here described. 



Generic Description.- — Size small, normal for the Tropidomantes. 

 Form slender, tegmina and wings narrower than in Tropidomantis, 

 but with apices rather broadly rounded, similar to the type developed 

 in Xanthomantis and suggesting the type found in the widely sepa- 

 rated genera Leptomantis and Aetaella. Head broad, facial clypeus 

 transverse with dorsal margin scarcely defined, occiput scarcely 

 raised above eyes, showing a broad and weak concavity mesad, 

 these features as in Xanthomantis. Ventral ocellus smaller than 

 the dorsal pair of ocelli and placed at a slightly greater distance 

 from them than the width between them. Pronotum slender, 

 slightly longer than the cephalic coxa, margins smooth, supra-coxal 

 expansion weak with its margins broadly convex, medio-longitudinal 

 carina heavy, * lamellate, percurrent, completely severed by the 

 transverse supra-coxal sulcus; in all these features agreeing with 

 Xanthomantis, except that in that genus the carina disappears 

 before reaching the cephahc margin of the collar, Tegmina and 

 wings narrow, with venation as characteristic for the group, clear 

 hyaline except external section of marginal field of tegmina and 

 distal portion of external section of marginal field of wings, which 

 very narrow portions are opaque, wings projecting well beyond 

 tegmina; these features giving to the insect a decided general re- 

 semblance to Xanthomantis and causing individuals of these genera 

 to have a close superficial resemblance to certain Neuropteroid 

 genera of the subfamily Mantispinae. Cephalic coxa with margins 

 smooth. Cephalic femur slender, dorsal margin straight and smooth, 

 unguicular sulcus near base; three discoidal spines; ventro-external 

 margin with four elongate and slender spines, between but slightly 

 outside of the first two of which is a small round concarity, into 

 which fits the apex of the terminal spine of the ventro-external 

 margin of the cephalic tibia when the limbs are flexed, genicular 

 areas unarmed; spines on ventro-internal margin fewer and not 



