] 06 F - H - Grravely. 



The three species of tliis genus may be recognised as follows: — 



1. Head entirely smooth and polished; outer tubercles long and simply 

 truncate H. glaber. n. sp. 



- Head more or less rngose in front; outer tubercles much shorter, 

 not simply truncate '2 



2. Both outer tubercles composed of two blunt denticles, scars of pro- 

 notum without punctures or hair. . .TL.impar, KUWERT, 1898, p. 318. 



- Inner denticle of riglit outer tubercle obsolete, scars of pronotuin 

 with hair-bearing punctures H. gracilis (HELLER 1910, p. 16). 



It is possible that Ladies infantilis and puerüis, KAUP (1871. p. 48), 

 also belong to tliis genus. 



Hyperplesthenus glaber, n. sp. 



Described from a Single specimen from New Guinea in tlie British 

 Museum collection. 



Length 40,5 mm. The anterior margin of the labrum is slightly 

 concave and the sides are straight and parallel; the angles are rounded, 

 the left one being scarcely more prominent than the right. The upper 

 tooth of both mandibles is obtuse and not very strongly developped ;. 



r 



Fig. 2 A. 

 Head of Hyperplesthenus glaber, n. sp. x 4. 



the three terminal teeth and the anterior lower tooth are conical, weli- 

 developed and perfectly distinct one from another on both sides. The 

 scars of the mentum are broad and straight; they are not united behind 

 in the specimen before me. Behind them a band of fine hair-bearing 

 punctures extends transversely just in front of the posterior margin, 

 uniting a pair of more coarsely punctured areas which occupy the posterior 

 angles of the mentum. The remaining surface of the mentum is polished 



