Coleopterological Notices, V. 329 



thorax two-thirds wider than long, widest just before the middle where the 

 sides are broadly, evenly arouate, becoming convergent and straight in basal 

 lialf; base and apex equal, the former feebly arcuate, the latter truncate; 

 basal angles obtuse ; disk with a large and very deep oval excavation, occupy- 

 ing more than median third and extending from base to apex. Elytra large, 

 nearly one-half wider and longer than the prothorax, the humeri broadly ex- 

 posed. Abdomen distinctly narrower than the elytra, the sides straight, just 

 visibly convergent from the base, the fourth and fifth segments equal in length. 

 Length (abdomen strongly contracted and reflexed) 2.1 mm. ; width 0.9 mm. 



Colorado. 



The abdomen is strongly reflexile in both of these species, and 

 the male described above has large discal processes on the second 

 and third segments, almost precisely similar to those of the preced- 

 ing species. So close a resemblance in these peculiar sexual marks 

 is indeed singular, in view of the great differences in antennal and 

 tarsal structure and coloration of the body. I think that these 

 large tuberosities may possibly have some function in limiting the 

 reflexibility of the abdomen. 



AlVEPSIOTA n. gen. 



Body parallel, moderately stout and rather feebly convex. Head 

 oval, longer than v^ade, well inserted but borne on a neck which is 

 not more than one-half as broad as the width across the eyes, the 

 latter small, at nearly twice their length from the base, the tempora 

 broadly rounded and convergent behind them. Antennae long, 

 moderately incrassate, loose, the erect setae extremely short, the 

 basal joint slightly longer and thicker than the second; third rather 

 longer than the second, both elongate, obconical and similar; fourth 

 to tenth increasing in width, the former longer than wide, the latter 

 slightly wider than long ; eleventh long, ogival, finely pointed, 

 barely as long as the two preceding. Mentum moderate, trape- 

 zoidal, the transverse suture at its base almost obsolete but better 

 marked at the sides because of the lateral impressions of the men- 

 tum. Ligula stout, short, the apical process well developed, split 

 to its base, the two lobes subparallel, long and moderately slender. 

 Labial palpi three-jointed, the basal joint stout, cylindrical, long, 

 more than twice as long as the second, which is a little narrower 

 and not longer than wide ; third slender, oblique, not as long as 

 the first. Maxillary palpi long and well developed, the third joint 

 obconical, a little longer than the second. Infralateral carina obso- 

 An^'als N. Y. Acad. Sci., VII, Oct. 1893.— 22 



