386 Memoirs on the Coleoptera 



the sexes; antennal club about as long as the funicle (cT) or little 

 shorter ( 9 ) ; prothorax larger than in the preceding, the arcuate 

 sides somewhat less converging; punctures not quite so coarse, nar- 

 rowly but distinctly separated; elytra shorter, of the usual oblong 

 form, more rapidly obtuse at apex than in captiosa, a third wider 

 than the prothorax and not quite three times as long; interstitial 

 punctures finer and rather sparser, confused, the suberect setiform 

 squamules a little shorter; male abdomen moderately impressed 

 medio-basally through nearly the first two segments. Length 

 (cf 9 ) 3.2-3.6 mm;; width i. 2-1. 35 mm. California (southern coast 



regions). Nine specimens crotchi Lee. 



7 — Body smaller, not so stout, shining, black; beak subsimilar in the 

 sexes, feebly arcuate, bristling and densely sculptured, more slender 

 than in the preceding, barely {(^) or distinctly (9 ) longer than the 

 head and prothorax, the antennal club full}' as long as the funicle 

 or longer, especially in the male; prothorax less strongly conical, the 

 apex more than half as wide as the base, the sides subevenly but 

 rather strongly arcuate; punctures notably coarse and deep, nar- 

 rowly separated; elytra in outline as in the preceding but fully two- 

 fifths wider than the prothorax and about three times as long; 

 striae rather coarse and deep; intervals equal, barely more than twice 

 as wide as the grooves, not quite flat, with stronger and subuniserial 

 punctures; male abdomen very feebly impressed medio-basally. 

 Length (cf' 9 ) 2.8-3.1 mm.; width 1.15-1.25 mm. Arizona 

 (probably southern). Two examples cylindrifera Csy. 



These various forms are mingled together in most collections, 

 but closer study shows that there are a number of very evident 

 structural differences among them. 



Geraeus Pasc. 



As previously stated (Ann. N. Y. Acad., VI, p. 573), under sub- 

 genus IV, there is a certain pecuHarity in mandibular structure, 

 which distinguishes Centrinus senilis Gyll., from any of the allied 

 forms, they being divaricate apically, with more or less arcuate 

 inner margin. This should be considered a generic, rather than 

 subgeneric, character, and affords a beginning for the division of 

 the very numerous small Centrinus-like North American species into 

 separate genera. Centrinus senilis was made the type of Gerceiis 

 by Pascoe, and several specimens sent me by Mr. Champion show 

 that the Arizona species, which I described in some detail under 

 the name senilis, is not that species at all. I therefore assign to it a 

 new name as follows: 



Geraeus balteatus n. sp. — Centrinus senilis Csy., nee Gyll. (1. c, p. 589) ; 

 senilis Chmp. (Biol. Cent.-Amer., IV, 5, p. 265). Arizona (Sta. Rita 

 Mts.). 



