1856.] Entomological Papers. 527 



Caput parvum, inter antennas linea latitudinali abbreviata hnpres- 

 sum. Labrum integram, punctis 3-impressum, puncto intermedio 

 bi-, lateralibus uni-setigeribus. Mandibulae validae prominentes. Palpi 

 art. ultimo elongato-ovato, apice leviter truncate Menti dens apice 

 truncatus leviterque sinuatus. Antennae art. 3° quarto aequali nisi 

 paulo breviore. Thorax amplus basi elytris applicatus, apicem versus 

 angustatus, angulis posterioribus subdepressis translucentibus, ante 

 scutellum leviter sinuosus, ante sinum obsolete latitudinaliter im- 

 pressus. Elytra striata, cum thorace angustissime marginata. Pedes 

 validae, ant. tibiis apice intus uni — , intermed. et post, bi-calcaratis. 



Specimen singulum f. in ripis lacus Oolombensis sub vegetab. 

 putrescent, legi. 



As already one species with a bifid mentum tooth (O. pulcher) 

 has been received into this genus, I have waved the hesitation I should 

 otherwise have felt in referring to it the present one,the tooth of which 

 is of a similar description. I have not seen the 0. pulcher, but as it is 

 said to be an inhabitant of this part of the world it may possibly 

 be identical with my species. If not, they might, as the g. is other- 

 wise pretty constant in its characteristics, be separated under a new 

 name as types peculiar to India. Besides the abnormal mentum 

 tooth the insect has not much to distinguish it from others of the 

 genus. The labrum is, however, peculiar, being entire, or even very 

 slightly produced in the middle, with the angles rounded off; it is 

 impressed near the anterior margin, with 3 deep punctures, the cen- 

 tral one of which is furnished with 2, the lateral ones with one 

 strong bristle each. The anterior tibiae are but slightly notched. 

 The prosternum is largely developed, reaching beyond the anterior 

 coxae, obtusely acuminated, and received in a deep excavation of the 

 mesothorax. But I doubt whether the development is sufficiently 

 large to entitle the insect to a place in the g. Lonchosternus Laf. 

 which, however, I have not seen in nature. 



16. Tvichoptei'yx cursitans. N. 



T. ovata, subconvexa, pubescens, supra obscure aenea, elytris aeneo 

 — brunneis, subtus picea, pedibus oreque testaceis, antennis art. 

 3-11 nigrescentibus. Long. corp. f lin. 



Antennarum clava art. 2 primis ovatis, ultimo conico, acuminato. 



