274 ^Ir. D. Sharp's Contributions to the 



quadrate. Head about as broad as the thorax ; the sides 

 rounded behind the eyes, towards the narrow neck, pitchy 

 in colour, sliining, rather coarsely and closely punctured. 

 Thorax nearly as long as broad, its greatest breadth in 

 front of the middle, greatly narrowed towards the front, 

 and much towards the base ; rather coarsely and moderately 

 closely, but obsoletely punctured, with a broad line along 

 the middle smooth. Elytra a good deal broader and longer 

 than the thorax, shining and impunctate, pitchy, with the 

 extremity broadly yellow. Hind body reddish-yellow, very 

 obsoletely punctured. Legs yellow. 



In the male the hind margin of the ventx'al plate of the 

 7th segment of the hind body is emarginate, and the 

 following segment bears a very broad and deep excision. 



Tapajos ; a single individual. 



EcniASTER. 



Of this remarkable genus only six species liave been yet 

 described, viz., three from Northern South America, one 

 from Chili, and two from the United States of Xorth 

 xVmerica. I here describe ten (or perhaps only nine) new 

 species, which show a striking variation in form of different 

 parts of the body, and leave no doubt that many other 

 species will be discovered ; indeed, I have already two 

 others from liio Janeiro, very dissimilar to any here 

 described. 



A highly important character of the genus appears 

 hitherto to have escaped notice, viz., that the prothorax 

 behind the front coxjb is horny. This character, in con- 

 junction Avith the others indicated for the genus, gives 

 it an isolated position in the Pcederidce, and renders it 

 probable that it will prove to be one of the most important 

 of the genera of South American Staphi/Unidce ; and also 

 that, notwithstanding the extension of one or two species 

 into Chili and North America, Echiaster aa411 be one of 

 the most characteristic genera of the Austro-Columbian 

 Coleoptera. Kraatz has described a genus from East India 

 {Sclerochiton, Kr. Staph. Faun, von Ostind. pi. ii. f. 8), 

 which appears to possess several points of relationship with 

 Kchiastir, and to be at present its neai'est known ally; it 

 is doubtful, however, to what extent the resemblances be- 

 tween the two genera indicate a real affinity between them. 

 Kraatz indeed in his figure and description gives us no 

 reason to suppose that iiclerochiton possesses that peculiar 



