310 RHYNCHOPHORA. 
long, subtriangular, hollowed along the suture at the base; sharply punctate-striate, the interstices flat 
and almost smooth. Beneath closely punctate. Prosternum unimpressed behind the transverse subapical 
groove. Tibie and tarsi slender, the tibie strongly unguiculate in the ¢, the anterior pair somewhat 
curved at the apex in this sex; tarsal claws very slender, long, and divergent. 
Length 23, breadth 14 millim. (¢ 2.) 
Hab. Mexico, Chilpancingo (H. H. Smith). 
One pair. A small, narrow form, with glabrous, polished, deeply striate elytra, 
and short, squamose prothorax, the rostrum much thickened at the base and flattened 
thence to the apex. The mandibles are short and slightly decussate, and the species, 
therefore, will probably have to be removed eventually from the present genus. 
CENTRINOPUS. 
Centrinopus, Casey, Ann. N. York Acad. Sci. vi. pp. 467, 601 (1892). 
Two minute forms were referred to this genus by Casey, specimens of which I 
have received either from him or from Mr. Wickham, and both of these, and three 
others, are now recorded from within our limits, partly on the authority of examples 
labelled “‘ Mexico (Zruquz)” in the Fry collection at the British Museum. Centrinopus 
will probably have to be sunk as synonymous with Gerewus. The type, C. helvinus, has 
abruptly bent prosternal processes in the male, but no value can be attached to this 
character. C. erythropus has an unarmed prosternum and it may not really belong here. 
1. Centrinopus alternatus. (Tab. XVI. fig. 23, 2.) 
Centrinopus alternatus, Casey, Ann. N. York Acad. Sci. vi. pp. 601, 602 (?)'; vii. p. 599%. 
Centrinopus helvinus, Casey, op. cit. vi. pp. 601, 602 (¢ 2)*. 
Hab. Nortu America, Maryland}, Indiana ?, Illinois 3, Ohio.—Mzxxico (Zruqui, in 
Mus, Brit.: 9); Nicaragua, Managua (Solari: 3 2.) 
I have seen three specimens of the var. helvinus of this species from Nicaragua, 
and one of each form from Mexico, agreeing with others from the United States 
communicated by Mr. Wickham and Capt. Casey. The male of C. alternatus before 
me has the prosternal spines rather short and curved, while that of C. helvinus has 
them longer and angulate (as described by Casey), and it is probable, therefore, that 
the spines vary in length and development, as is often the case in Gereus. 
2. Centrinopus mistus, sp.n. (Tab. XVI. figg. 24, 24a, 3.) 
Elliptic, narrow, nigro-piceous, the antenna, tibie, and tarsi ferruginous ; thickly clothed with narrow inter- 
mixed brown and white scales, the latter condensed into three faint lines on the prothorax and a dense 
spot on the scutellum, the scattered white scales on the elytra nowhere condensed into spots ; the vestiture 
of the under surface close and white. Head closely punctate; rostrum arcuate, rather slender, thickened 
towards the base, a little longer than the head and prothorax, striate and ciosely punctate in the J, 
smoother in the 2, the antenne inserted slightly behind the middle, joint 1 of the funiculus long, the 
others short, the club ovate. Prothorax transverse, narrowing from near the base, feebly constricted in 
front ; densely, finely punctate. Elytra narrowing from the base, flattened on the disc anteriorly, finely 
punctate-striate, the interstices rugulose. Beneath densely punctate; first ventral segment broadly 
