124 Coleopterological Notices. 



antennae which is not constricted in apical third, and in the form of 

 the fourth joint of the maxillary palpi which is distinctly more 

 robust and securiform. 



It resembles Olibrus in the mode of antennal insertion, but differs 

 radically in this respect from Phalacrus. Its relationship with 

 Acylomus and Litolibrus has been mentioned under those genera. 



The posterior tibial spurs are generally very small, slender and 

 subequal. and in some species become quite as insignificant as in 

 Phalacrus. The basal joints of the posterior tarsi are simply densely 

 setose beneath, the second joint being but moderately elongate, 

 generally nearly twice as long as the first, but in nitidus relatively 

 shorter and but slightly longer than the first. The sculpture varies 

 from the completely polished, as seen in apicalis, to a rather coarse 

 and very strong reticulation throughout the upper surface, as seen 

 in suhalutaceus. The punctures are generally very minute and 

 obscure, sometimes almost completely obsolete, the broadly crescen- 

 tiform type being rare and exceptional. In pusillus, modestus, 

 atfenuatus, and elongatulus, the punctures become deeper and more 

 distinct on certain limited portions of the elytral disk. 



Our species are moderately abundant, usually widely distributed, 

 and are somewhat diversified in structure. The four species as- 

 signed to group II, differ each very greatly from those of group I, 

 in several peculiarities of structure or sculpture, but at the same 

 time differ from each other to quite as great a degree. In general, 

 the reticulation of the elytral surface, when present, is relatively 

 somewhat coarse, and does not exhibit the transversely wavy lines 

 so perfectly as in Acylomus; in convergens and atlenuatus it is 

 replaced by a very minute wavy strigilation which, however, is 

 not sufficiently fine to produce an opalescent effect as in Litolibrus. 



The following table will probably enable the student to recognize 

 those species which I have been able to study : — 



Spiniiles at the apex of the prosternal process long and conspicuous I 



Punctures of the second and third elytral series not more distinct in the 

 middle. 

 Elytra either entirely pale or very distinctly paler at the apex. 



Elytra highly polished, not reticulate except sometimes very feebly 

 toward apex ; punctures excessively minute and scarcely visible. 

 Elytra paler at apex. 



Form narrowly oval, piceous, each elytron abruptly and ohliquf^ly 

 paler at apex apicalis 



