PHALACRID^E 85 



and integer, have a densely spongiose pad on the under surface of 

 the second hind tarsal joint in the male, which is wanting altogether 

 on the more slender joint of the female. In the peculiar submaculatus 

 group, embracing so far as known Olibrus submaculatus Shp., and 

 Acylomus nebulosus Csy., there is a similar dense pad in the male. 

 In other smaller species the males, as known by the peculiar ob- 

 triangular form of the tibiae, have no inferior pad but merely a loose 

 coarse pubescence on the second joint, which is slender as in the 

 females of the aciculatus group. The prosternal process is of less 

 moment taxonomically here than in Stilbus, the setae generally being 

 very short and inconstant, but in the aciculatus group, these setae 

 become long, extremely stiff and subspiniform. In the sub- 

 maculatus group, having identical hind tarsi, they are simple hairs, 

 and in this group the ground sculpture of the elytra is more reticu- 

 late than strigilate. In the smaller species, as represented by 

 calcaratus, there are but few short hairs. A general study of the 

 genus would therefore lead to a grouping based upon rather decided 

 structural characters, which however do not seem to be subgeneric 

 in any sense, the peculiar elytral sculpture being extremely constant 

 throughout. The geographic grouping here followed is merely pro- 

 visional and for convenience in identification. 



Submaculatus Shp. (Olibrus) is represented before me by two speci- 

 mens, taken by Wickham at Puente de Ixtla, Morelos. It resembles 

 nebulosus very closely and, indeed, the two forms may be subspecific 

 in relationship, but submaculatus is more abbreviated, so that the 

 longitudinal distance between the pairs of elytral pale spots is much 

 less than it is in nebulosus and this seemingly trivial difference is 

 perfectly constant among the six specimens of the two forms. 



In addition to the species described above, there are at hand 

 examples of three other species from Mexico and Central America, 

 but they are obscure forms and it is inadvisable to describe them in 

 the absence of typical examples of the rather numerous allied species 

 described by Dr. Sharp under Olibrus. It is rather surprising that 

 the relationship of the latter species with Acylomus aciculatus did 

 not occur to the author. 



Erythrolitus n. gen. 



*The above name is proposed for the Olibrus rubens of LeConte, 

 which constitutes a genus near but not identical with the Central 



