270 RHYNCHOPHORA. 
Hab. Mexico (coll. Sommer’; Flohr), Juquila in Oaxaca (Sallé*). 
Mr. Janson has lent us the types of this insect (¢ 2) from the Sommer collection, 
and I have seen about a dozen others, including a series from Juquila. The species 
is scarcely recognizable from Boheman’s description. The mottled vestiture and erect 
sete, the truncate base of the prothorax, the basally depressed, subcarinate rostrum, 
and the prominent eyes are its chief characters. ‘The scales are metallic green on the 
legs and under surface in the type (¢) (fig. 16) and some of the other examples | 
before me. 
CHAULIOPLEURUS, gen. nov. 
Elytra with the flanks subangularly dilated or tumid below the humeri, the lower margin strongly sinuate, 
the humeri somewhat prominent in the fully winged type, obtuse in the other species, the supplementary 
strie present; rostrum widened anteriorly, uni- or tricarinate, the nasal plate triangular, bare, the 
scrobes lateral, deep, and descending; eyes large, not prominent; antennal scape about reaching the 
anterior margin of the prothorax ; scutellum small; tibise convex on their outer edge, the posterior pair 
narrowly laminate and biciliate at the apex, denticulate along their outer half within (at least in 9 ), and 
with the glabrous articular surface large; body polished and almost bare in the type, the depressions of 
the prothorax and elytra squamose in C. guadrifoveatus ; wings fuliy developed or rudimentary. 
Type, C. adipatus. 
The three Costa Rican forms referred to this genus approach Exophthalmus jeke- 
lianus and its allies, but are readily separable therefrom by the peculiar shape of their 
elytra. They all have the meso- and metasternal side-pieces largely developed, as 
usual in the winged forms. The three species, the type being only constantly winged, 
differ greatly in general facies: C. adipatus has inflated, subglabrous, polished elytra 
and the humeri prominent; C. rufovittatus is flattened on the disc and has rufo-vittate 
elytra; C. quadrifoveatus has the disc of the prothorax and the base of the elytra (behind 
the scutellum and on the outer part of the disc) deeply excavate, and the depressed 
spaces squamose. The last-mentioned insect approaches Synthlibonotus, Schonh. (type 
S. rufipes, Lacord.), but differs from it in having less inflated, 10-striate elytra, the 
scrobes more strictly lateral, the metathoracic episterna more dilated anteriorly, &c. 
1. Chauliopleurus adipatus, sp.n. (Tab. XII. figg. 17, 174, 3.) 
Moderately elongate, acuminate-ovate, narrow ( ), broader ( @ ), shining, black, the femora (the apices excepted) 
and tibise rufous; when fresh clothed towards the sides (above and beneath), and on the tarsi above, with 
scattered minute blue scales, which give a pruinose appearance to the surface, the elytra also with a few 
semierect white sete. Rostrum a little longer than broad, sparsely punctate, convexly raised or sub- 
carinate down the middle, the inter-ocular fovea small; antenne rather slender, the scape reaching the 
front of the prothorax ; eyes not prominent. Prothorax broader than long, feebly bisinuate at the base, 
subconical in 9, the sides parallel behind in ¢ ; broadly depressed and obsoletely canaliculate down the 
middle, the disc with a few scattered intermixed minute and larger punctures, and sometimes trans- 
versely wrinkled, the sides confluently foveolate. Scutellum small. Elytra inflated, oblong-subtriangular 
in gd, broader and widened to the middle in @, transversely depressed at the base, and with an 
oblong smooth tuberculiform prominence on the flanks between the two outer strie below the humeri, the 
latter tumid, the apices sharply, separately mucronate; finely seriate-punctate, the interstices flat, 
obsoletely punctate and usually transversely wrinkled towards the sides. Femora and tibie shining and 
