320 ; RHYNCHOPHORA. 
subquadrate ; elytra elongate; pygidium not visible ; prosternum unarmed, unimpressed behind the 
transverse subapical groove ; anterior coxe large, exserted, separated by about one-third their own width ; 
the ascending portion of the mesothoracic epimeron narrow, curved, and somewhat swollen at the tip, 
the flanks of the prothorax below the hind angles more or less hollowed for its reception (see fig. 35 a) ; 
femora unarmed ; tibie strongly unguiculate; tarsal claws long, divergent; body elongate-rhomboidal, 
squamose. 
Type, Ps. macropterus. 
The single species referred to this genus is not uncommon in Western and 
N.-Western Mexico. It is perhaps most nearly related to Centrinogyna, Casey, which, 
however, has a large, vertical, and completely exposed pygidium in the male, &c. In the 
present genus the ascending portion of the mesothoracic epimera is often tuberculiform, 
as seen from above. The curved, decussate mandibles and the relatively elongate elytra 
separate Pseudogereus from Gereus. 
1. Pseudogerzeus macropterus, sp.n. (Tab. XVI. figg. 35, 354, 3.) 
Nigro-piceous or black, the tibia sometimes ferruginous ; thickly clothed with small narrow whitish and 
brown scales, the pallid scales mainly condensed along the sides and middle of the prothorax and on the 
alternate elytral interstices (these latter with three or four, and the others with two, rows of scales) ; 
the vestiture of the under surface close and whitish. Head closely punctate; rostrum stout, strongly 
arcuate, slightly longer than the head and prothorax, somewhat compressed at the sides in its basal half, 
closely striato-punctate, the apical portion smoother in the 9, the antenne inserted at a little beyond 
the middle. Prothorax broader than long, constricted in front. the sides gradually and arcuately con- 
verging from the base ; densely, finely punctate, and often with indications of a smooth abbreviated median 
line, the narrow interspaces raised into sinuous longitudinal ridges. Elytra gradually narrowing from 
the obliquely truncated humeri; narrowly striate, the interstices closely punctate, the alternate ones in 
some specimens wider than the others. Beneath densely punctate; first ventral segment broadly 
depressed down the middle in the ¢. Anterior tibiz hollowed within and slightly bowed in the ¢. 
Length 34-43, breadth 14-21, millim. (¢ 2.) 
Hab. Mexico, Ventanas and Milpas in Durango (forrer), Omilteme and Chilpan- 
cingo in Guerrero (H. H. Smith). 
Twelve specimens from Guerrero and six from Durango. The vestiture of the upper 
surface varies in colour, and it is denser in most of the examples from Guerrero, which 
are taken as the types, than in those from the other localities. 
CENTRINITES. 
Centrinites, Casey, Ann. N. York Acad. Sci. vi. pp. 468, 615 (1892). 
This genus is based upon a single N.-American species, C. strigicollis, Casey, and 
several others. from Mexico and Central America are now added. It mainly differs 
from Gerewus (=Centrinus, Casey) in the feebly decussate, curved, slightly notched 
mandibles and the coarsely sculptured surface of the body. Three of the new forms 
described have the intermediate and posterior tibia more or less thickened, and 
dentate just beyond the middle beneath, and the prosternum bispinose, in the male, 
