220 PROCEEDINGS OF THE ACADEMY OF [June, 



Description of Type. — Size small; form depressed, compact; surface 

 covered heavily with scales. Head ovoid, occipital outline depressed, 



Fig. 21. — Oligacanthopus prograptus. Internal face of caudal metatarsus and 

 internal tibial spurs. (Greatly magnified.) 



weakly arcuate dorsad; interantennal protuberance separated from 

 vertex by a well-marked transverse interantennal sulcus. Maxillary 

 palpi with penultimate joint not more than two-thirds as long as 

 terminal joint, the latter gently expanding distad, gently obliquely 

 truncate. Pronotum with dorsum transversely very gently arcuate, 

 curving sharply laterad, caudal width subequal to length, lateral 

 outlines of disk straight, subparallel; lateral lobes passing into disk 

 with an angulation but slightly indicated, depth of lobes over one- 

 quarter their greatest length, ventral margin sinuato-truncate. 

 Subgenital plate arcuato-trigonal, subcompressed. Ovipositor 

 shorter than caudal femur, gradually thickened proximad, very 

 gently arcuato-convex, somewhat elongate sublanceolate at apex, 

 the surface of apex smooth, the ventral margins of the ventral valves 

 armed distad with a row of minute serrulations. No tympanum pres- 

 ent on the cephalic tibiae. Caudal tibiae straight ; armament of same 

 similar to that found in Cycloptilum, but greatly reduced in size, much 

 smaller than in any other known North American species of the 

 Mogoplistii, the medio-external spur nearly twice the length of the 

 dorso- and ventro-external spurs. Caudal metatarsus straight, 

 subcompressed; distal spurs reduced to very small heavy teeth 

 which are sharply upcurved distad and scarcely reach the base of the 



Fig. 22. — Oligacanthopus pro- 

 graptus. Apex of ovipositor. Fig. 23. — Oligacanthopus prograptus. Ceph- 

 (Greatly magnified.) alic aspect of head. (Much enlarged.) 



second tarsal joint, which is twice the length of one of these external 

 spurs; these, as is true also in the tarsal spurs, are longer than the 

 homologous internal spurs. 



