312 RHYNCHOPHORA. 
| NICENTRUS. 
Nicentrus, Casey, Ann. N. York Acad. Sci. vi. pp. 468, 608 (1892). 
Seven N.-American species are referred to this genus, the type of which is Centrinus 
lineicollis, Boh., ard several others from our region are now added. They are separable 
from Gereus by their more oblong form, and in having the elytra very little wider than 
the prothorax, with the humeri not at all prominent; and from Limnobaris by the less 
decussate mandibles. ‘The prosternum is unarmed in the male, and the sexual differ- 
ences are not very conspicuous. Some of the Central-American forms resemble Barinus 
curticollis and B. squamolineatus, Casey, but they differ from that genus in having the 
tarsal claws free, the rostrum much less abruptly curved, and the first joint of the 
funiculus less elongate. In two of them the antericr and intermediate knees are more 
or less spinous or angulate at the apex (as in various Zygopids), the femora are shallowly 
sulcate beneath, and the mandibles are slightly decussate at the apex. ‘The Central- 
American species may be grouped thus :— | 
a. Mandibles (as seen closed) straight on their inner edge. 
a’. Mandibles not angulate at the sides beneath. . . . . . . =. + © « Species 1-8. 
b*. Mandibles conspicuously angulate at the sides beneath . . . . . . « Species 4. 
b. Mandibles (as seen closed) short, slightly decussate at the tip. 
c’. Anterior and intermediate knees rounded. . . . . . «. «. + © « « Species 5-8. 
d'. Anterior and intermediate knees spinous or angulate. 
a’. Femora sulcate from about the middle beneath . . . . . . . « « Species 9, 10. 
b’. Femora sulcate at the apex only beneath . . . . . . . . =. ~~ +. Species 11, 
1. Nicentrus lineicollis. (Tab. XVI. figg. 25, 25a, ¢.) 
Centrinus lineicollis, Boh. in Schénh. Gen. Cure. vill. 1, p. 221° (nec C. lineicollis, Lec. Proc. 
Am Phil. Soc. xv. p. 313, and Nicentrus lineicollis, Casey, Ann. N. York Acad. Sci. vi. 
p. 609). 
Nicentrus ingenuus, Casey, loc. cit. pp. 609, 610. 
Hab. Norta America, Illinois, lowa, and Texas?.—Merxico! (Dupont and Truqui, 
in Brit. Mus.), Toxpam (Sallé), Cerro de Plumas, Jalapa, Oaxaca (Hoge), Cordova 
(U.S. Nat. Mus.), Teapa (Sallé, Hoge, H. H. Smith), Vera Cruz, Atoyac, Orizaba (H. H. 
Smith), Temax in N. Yucatan (Gaumer); GuaTeMALa, San Gerénimo, Chiacam, Cahabon 
(Champion); Nicaragua, Chontales (Janson); Costa Rica, Irazu (Rogers), San José, 
Caché, Guatuso, Patarra, Higuito (Biolley), Zent, Puerto Limon (U.S. Nat. Mus.) ; 
Panama, Bugaba, Volcan de Chiriqui, San Feliz (Champion), Tabernilla (U.S. Nat. Mus.). 
A common species in Mexico and Central America, and found, according to Biolley, 
on Polygonum punctatum, Elliot, and.on a species of Croton. The North-American 
specimens referred to JV. linetcollis by Casey, two of which are before me, belong to a 
different species *: they are narrower and more parallel-sided, the surface is duller, 
* The name J. lecontei is suggested for this species. 
