114 RHYNCHOPHORA. 
elytra. The sexes, except in S. pollinosus, are not separable by external characters. 
The lateral prominences of the elytra vary in form according to the species, and 
gradually become obsolete, as in S. bicinctus. The genus is confined to Tropical 
America, ranging as far north as Mexico, and extending to the Antillean Islands. 
The Central-American species may be arranged under four main groups by the 
armature of the legs, thus :— 
1. All the femora dentate, and the tibie more or less distinctly denticulate, 
serrulate, or simply setose along their inner edge, the latter also with a sub- 
median tooth or angular dilatation . 2. - 6 ee + ew ee es Species 1-5. 
9. Anterior and intermediate femora acutely dentate (and the posterior pair 
feebly so in S. aurocinctus), the tibie setose along their inner edge. 
a. Elytra spotted, the lateral prominences subconical. . . . . . ~. « + Species 6. 
b. Elytra bifasciate, the lateral prominences obtuse . . . . . +. + « Species 7. 
3. Anterior femora feebly dentate. 
c. Elytra bicaudate towards the apex, immaculate; tibie denticulate, but 
without longer submedian tooth Loe ee ee ee ee) «Species 8. 
d. Elytra without prominences, transversely bifasciate ; tibiee setose along their 
inneredge . 6 6 6 ee ee ee ee Species 9. 
4, All the femora unarmed. 
e. Tibize denticulate, and also with a longer submedian tooth . . . . =. - Species 10, 11. 
f. Tibiz simply setose or pilose along their inner edge, or at most armed with 
a minute submedian tooth (S. pollinosus, 3). 
a'. Elytra transversely bifasciate, the lateral prominences obtuse or obsolete. Species 12. 
b!. Elytra without well-defined fasciz, the lateral prominences angular . . Species 13. 
1. Sternechus extortus. (Tab. VII. figg. 17, 17 a, 0.) 
Sternechus extortus, Chevr. Col. Mex., cent. i. fasc. 1, no. 18 (June 1833)’. 
Hab. Mexico, Boca del Monte ! (Sallé!), Cuernavaca (Sallé, H. H. Smith), Misantla 
(Hoge). 
Var. a. denudatus. (Tab. VII. fig. 18.) 
The smooth, bare spaces on the elytra reduced in extent, not forming fascie. 
Sternechus denudatus, Boh. in Schénh. Gen. Cure. vii. 2, p. 861 (1848) *. 
Hab. Mzxico (Sallé, ex coll. Sturm), Sierra de Durango (Flohr), Toxpam, Etla, 
Yolotepec, Oaxaca (Sallé), Jalapa (Hoge). 
Var. 2. reticulatus,n. (Tab. VIL. fig. 19.) 
The smooth, bare spaces on the elytra still smaller, the raised alternate interstices sinuous and much interrupted, 
and here and there connected by smooth, sinuous, feeble elevations. 
Hab. Mexico, Amula and Omilteme in Guerrero (H. H. Smith). 
Not rare in Mexico, and varying a good deal in the elytral sculpture, the glabrous 
elevations on the alternate interstices gradually becoming more and more broken 
