260 THE CANADIAN ENTOMOLOGIST. 



Batrisodes, Reitt. 

 A very large genus possessing two types in America, one with the 

 head and antennse of the males curiously modified and in very diversified 

 manner, this type occurring in the Atlantic regions, and the other having 

 little or no sexual modification of the head and antennse, but with a 

 very large cavity near the apex of the male abdomen, this occurring only 

 in the true Pacific coast fauna. The polarity theory of sexual characters, 

 enunciated, I believe, by LeConte, is well illustrated by these two classes of 

 males. The following species deserve notice at the present time : 



Species of the Pacific regiotis. 

 Apart from 7}ionticola, distinguished by its deep black colour, 

 occidims, distinct in its short and rapidly-widening elytra, and cicatricosus, 

 denticauda and pygidialis, characterized by peculiarities of sculpture and 

 by the structure of the pygidium, there are at hand six closely-allied 

 smooth polished species, which may be distinguished among themselves 

 as follows : 



First dorsal segment with the two median basal elevations prolonged for 

 some distance posteriorly in slender carinas. Species of the interior 

 and more elevated regions 2 



First dorsal with the two basal elevations not or scarcely at all prolonged 

 posteriorly. Species of the coast regions 4 



2. Abdominal carinas separated by a distance which is distinctly less than 



that separating either from the inner line of the lateral margin. 

 Nevada (Reno) zephyriniis, Csy. 



Abdominal carinae more widely separated, the distance between them 

 about equal to that separating either from the inner line of the lateral 

 margin ; body a little stouter, the antennae rather more slender. ...3 



3. Anterior trans-verse margin of the abdominal excavation of the male 



feebly and narrowly arcuate and produced at the middle. Shining, 

 subimpunctate, sparsely but rather coarsely pubescent, testaceous, 

 though much darker than zephyrinus, the head and antennae nearly 

 similar and of the usual type in this group ; prothorax somewhat 

 longer than wide and a little narrower than the head, the median 

 * sulcus distinct to anterior two-fifths ; elytra nearly as long as wide, 

 broadly arcuate laterally, arcuately converging at the sides basally, 

 the humeri moderately tumid longitudinally ; three basal foveae on 

 each distinct, equal and perforate, the two inner very approximate, a 



