421 
of the Amazon Valley. 
Oculi supra longe distantes. Tubera antennifera vix 
elevata, distantia, lata, supra sulcata. Antenuge ar- 
ticulo Imo crasso, curvato, 3-10 elongatis, dilatatis, 
apice angulis productis, 3io casteris singulis duplo longiori, 
3-7 supra et infra late sulcatis et infra longe ciliatis, ^ 
magis, 9 minus elongatis. Thorax prope basin latera- 
liter profunde constrictus, deinde usque ad apicem an- 
gustatus, ibique anguste lateraliter constrictus, supra 
Isevissimus. Elytra elongata, apice obtuse truncata. 
Pedes breves, validi ; femora paulo incrassata ; tarsi 
breves, articulo prime triangulari. Mesosternum in 
medio tumidum. 
The difference in the form and clothing of the an- 
tennal joints of itself would scarcely warrant the separa- 
tion of this genus from Platyarthron ; but the form of 
the anterior part of the head, the short and extremely thick- 
ened muzzle, the very strong and sharply curved man- 
dibles, and the wide flattened shape of the antenniferous 
tubercles, form a combination of characters which forbid 
the association of the form with the genus in question. 
1. PJmrtosia ebenina, n. sp. 
Elongata, antice angustior, nigra, nitida, glabra; an- 
tennis, pedibus, et corpore subtus interdum piceis ; capite 
thoraceque vix punctulatis; elytris subtiliter coriaceis et 
punctulatis, utrinque linea angusta recta a basi usque 
ultra medium, lineolisque duabus exterioribus, albis. 
Long. 6i-7ilin. $ . 
Hah. — Para. One pair taken in copula. 
Genus Streptolabis. 
Bates, Entom. Monthly Mag. iv. 23 (1867) ; Lacord. 
Gen. ix. 153. 
Oblonga, elytris oblongo-quadratis, postice dilatatis, 
glabra. Caput parvum, angustum, mandibulis horizon- 
taliter porrectis et recurvis. Oculi baud prominentes, 
reniformes, supra longe distantes. Antennm robustse, 
glabrae, articulo 3io caeteris paulo longiori, 3-10 subser- 
ratis, supra et infra sulcatis. Thorax transversus, antice 
rotundato-attenuatus, antice et postice sulco profundo 
TRANS. ENT. SOC. 1870. PART IV. (DECEMBER.) G G 
