AMERICAN COLEOPTERA. 161 



Horn, but I have already given reasons for doubting the accuracy 

 of this reference. 



The Mojave and Needles examples are probably identical with 

 the Salton ones, but they show certain small differences which may 

 indicate a distinct though very closely allied species. In them the 

 antennal stem is rather less distinctly serrate and the club is a little 

 narrower; the elytra are also scarcely divaricate at apex. In the 

 Needles specimen there are very faint indications of elytral sulci, 

 but there is not the slightest indication of these in the others. 



OLIGOMERODR8 new genus. 

 This genus is established with some reluctance for two species 

 lying between Xeranobium and Oligomerus, the homogeneity of 

 neither of which I am willing to disturb by the introduction of the 

 species in question. From Xeranobium the present genus is distin- 

 guished by the entire prothoracic side margin, the slightly (occiden- 

 talis) or distinctly (catalince) emarginate fourth tarsal joint, the fee- 

 bly serrate antennal stem, the compressed terminal palpal joint with 

 more strongly rounded interior margin, the relatively shorter and 

 narrower penultimate joint of the labial palpi, the more or less evi- 

 dent elytral stria?, ami the much less dense pubescence. From Oli- 

 gomerus it differs notably in the more slender tarsi, the third joint 

 not at all emarginate, the terminal joint narrow and elongate, and 

 in the approximate middle coxa?. The two species resemble the 

 larger more elongate species of Xyletinus. They differ considerably 

 from each other in antennal and tarsal formation and may thus be 

 readily separated : 



Intermediate joints of antennae elongate, the ninth barely as long as the two 

 preceding united in either sex, the three outer joints together much 

 shorter than 1-8 united ; basal joint of hind tarsi equal to the next 

 two, fourth joint slightly emarginate; elytral striae distinctly punc- 

 tured 1. occidentals. 



Intermediate joints of antennae much smaller, the ninth evidently longer than 

 the two preceding united in the 9> an( ^ as l° n £ as t ne f" ve preceding 

 in the % ; three outer joints as long as ( 9 ) or ruuch longer ( % ) than 

 1-8 united ; basal joint of bind tarsi as long as the next three, fourth 

 joint rather deeply emarginate or bilobed ; elytral striae feebly or 

 scarcely punctured 2. calal iiui'. 



1. O. occidentalis n. sp. — Cylindrical, a little depressed, brown ; pubes- 

 cence short, appressed, ashy in color, plentiful, but not concealing the surface 

 sculpture. Head not visible from above in repose, three-fourths as wide as the 



TRANS. AM. ENT. SOC. XXXI. (21) MAY, 1905. 



