Brazilian Barusme 167 



gradually wider, the club large, oval, with distinct sutures and 

 almost as long as the entire funicle. The prosternun has a large and 

 transversely oval, very deep, polished excavation, limited at each 

 side by strong longitudinal tumidity, and, on the outer side, these 

 tumidities are deeply excavated. The anterior coxae are moder- 

 ately separated. The legs are slender, the femora mutic and the 

 tarsi rather small and narrow, with the third joint but slightly 

 dilated. The prothorax is strongly and abruptly tubulate, the 

 scutellum small, quadrate, flat, emarginate behind and the upper 

 surface is but feebly convex; the inflexed flanks of the elytra are 

 abruptly defined by one of the numerous longitudinal carinae. The 

 genus is without any near relative known to me and the type may 

 be described as follows: 



Crostis subexplanata n. sp. — Depressed and subrhombic-oval, very smooth, 

 polished, glabrous and impunctate throughout above and rufo-piceous, the 

 under surface with distinct and remotely scattered nude punctures, the distinct 

 and rather close-set punctures of the legs alone bearing pale setiform squamules; 

 beak thick, smooth, one-half longer than the head and prothorax, distinctly 

 arcuate; prothorax small, nearly a third wider than long, the sides cariniform, 

 converging and straight to near apical fourth, there rounding for a short distance 

 to the tubulation, which is three-fifths as wide as the base; surface smooth, 

 broadly subexplanate laterally to the acute margins; basal lobe moderate, rather 

 rapidly formed and narrowly rounded; elytra a third longer than wide, a third 

 wider than the prothorax and two and one-half times as long, the sides only 

 feebly converging and nearly straight from the rounded humeri to the middle, 

 then more strongly converging and nearly straight to the rather narrow apex, 

 each elytron being narrowly and strongly rounded at tip; surface with somewhat 

 strong, smooth and impunctate striae; intervals carinate, the carina of each near 

 the outer edge of the interval, the lateral interval — along the acute line forming 

 the upper margin of the inflexed flanks — wider than the others and subexplanate. 

 Length 2.2 mm.; width 1.15 mm. Brazil (Santarem). One specimen of un- 

 determined sex. 



The strongly lyrate elytra and acute explanate lateral margins of 

 both prothorax and elytra, are very striking characters of this 

 remarkable species. 



Crostidia n. gen. 



This genus resembles the preceding in a few features, but in 

 most respects is as completely isolated from any other. The body 

 is more convex, and the sides of the upper surface are obtusely 

 rounded in section as usual; the surfaces are almost completely 

 glabrous, the prothorax similarly tubulate and with the prosternal 

 excavation bounded externally by tumid ridges, which are excavated 

 on their outer sides, is also somewhat similar, but the beak is much 

 longer, thinner and punctured and the mandibles are straight, 

 prominent and non-decussate, having dentiform irregularity along 

 their inner margins near base; it is separated from the head by a 



