174 Memoirs on the Coleoptera 



gradual, strongly, subevenly rounded at apex; scutellum differing from that 

 of the preceding species in being more free, parallel, truncate, slightly longer 

 than wide and feebly, longitudinally impressed; elytra scarcely a fifth 

 longer than wide, rapidly parabolic, with less broadly rounded apex than in 

 any of the preceding, a little wider than the prothorax and three-fourths 

 longer; grooves a little coarser, deep, smooth, the sutural finer and crenulate; 

 flat intervals with single rather uneven series of minute but evident punc- 

 tures; abdomen strongly, evenly convex, finely and loosely punctate. Length 

 2.8 mm.; width 1.7 mm. Brazil (Santarem). One example. 



robustula n. sp. 



The smooth convex abdomen in all four unique types of the 

 above species, would seem to indicate the female, and it seems 

 probable that the male is unknown. It is surmisable, however, 

 that in that sex the prosternum is wholly unarmed. 



Dialomia n. gen. 



This genus is allied to the last but has a more rhombiform outline 

 and somewhat more distinct sparse hair-like squamules, which are 

 of the same general nature and distribution. The beak is longer, 

 strongly arcuate, evenly subcylindric, with strong sculpture of 

 longitudinal furrows, bearing setulose punctures, and is separated 

 from the head by a deeper transverse impression. The mandibles 

 are strongly bifid and arcuate but only moderately decussate. The 

 antennae are barely visibly behind the middle, the funicular joints 

 closely joined, gradually wider and merging very evenly into the 

 outline of the club, which is rather small, about as long as the three 

 preceding joints and with its first segment fully half the mass; 

 the first funicular joint is as long as the next two, the second much 

 longer than in the preceding genus and at least one-half longer than 

 wide. The prosternum has a very deep and elongate-oval excava- 

 tion, becoming extinct at the line of the coxae, which are well 

 separated. The femora are mutic, the prothorax abruptly tubulate 

 at apex and the scutellum small and oblong, the elytra rather 

 coarsely grooved. The prosternum has a short erect spine before 

 each coxa in the male. The only two species known to me are the 

 following: 



Form subrhomboid-oval, deep black, shining, the upper surface with slender 

 hair-like squamules, very remote and inconspicuous on the pronotum, longer 

 and more distinct but sparse and in single lines on the elytra, with a few 

 paler and more distinct basally; on the under surface each of the rather 

 coarse punctures bears a minute slender squamule; beak evenly, strongly 

 arcuate, moderately slender, fully half as long as the body; antennae piceous- 

 black; prothorax a little less (cf) or slightly more (9) than a third wider 

 than long, the sides converging and very feebly arcuate, rapidly rounding 

 apically to the tubulation, which is truncate and half as wide as the base; 

 surface with minute sparse punctulation, becoming rather close, strong 

 punctures toward the sides; basal lobe strong, with narrowly subtruncate 



