DESCRIPTIONS OP NEW SPECIES. 



Body long ovate, pale brown, fringed at the sides with hair. 

 Head rather longer than wide, coarsely and densely punctured, 

 black, clypeus rounded, strongly margined; antennas pale, 9- 

 jointed, joints 3 5 closely united, club longer than the stem. 

 Labrum very broadly and slightly concave. Thorax one-half 

 wider than long, considerably narrowed in front, strongly rounded 

 on the sides, with a distinct marginal line in front ; surface sparsely 

 punctured, yellow, with a very large transverse black spot, ex- 

 tending from the apex nearly to the base, where it is pointed. 

 Elytra strongly punctured, fringed at the sides with hairs. Be- 

 neath sparsely clothed with long hairs, tibiae and tarsi darker, 

 spurs of hind tibiae both movable, obtuse, claws armed with a 

 small tooth near the base. 



A species remarkable not only for the color of the thorax, but 

 by its anterior margin being thickened, and separated by a trans- 

 verse impressed line ; in Listrochelus the same marginal line is 

 seen, but to a much less extent. 



286. L. nitidula. Elongato-ovata, testacea nitida, capite fusco, for- 

 titer baud dense punctate, clypeo rotundato, marginato, apice obsolete 

 sinuato, thoraoe flavicante, apice marginato, parce punctate lateribus 

 valde rotundatis, parce fiuabriatis, elytris punctatis, margine parce fim- 

 briatis. Long. -45. 



Cape San Lucas ; Mr. John Xantus. Also resembles a small 

 Cyclocephala. Smaller than the preceding, with the thorax more 

 narrowed in front, and more rounded on the sides, and the clypeus 

 broader and slightly sinuate in front. In the female the tooth of 

 the tarsal claws is more prominent and near the middle of the 

 claw. The antennas of the male are as in the preceding. 



L,ISTROCHEL,US BLANCH. 



2S7. Li. densicollis. Elongatus cylindricus, piceo-rufus, capite tho- 

 raceque obscurioribus nitidis, illo fortiter punctato, angustius marginato, 

 antice late subtruncato, fronte sutura bene impressa, thorace confertim 

 fortiter punctato, lateribus obtuse angulatis, angulis posticis baud rotun- 

 datis ; elytris vage punctatis, glauco-pruinosis, tibiis posticis calcaribus 

 subaequalibus, tarsis tibiis paulo longioribus. Long. -62. 



Cape San Lucas ; John Xantus. Resembles in form L. mu- 

 coreus, but differs considerably by the characters above noted. 

 The sexual characters are as in that species. 



