540 RHYNCHOPHORA. 
SIRON, gen. nov. 
Second ventral segment very short, shorter than the third or fourth; elytra long, subcuneiform, flattened, 
interruptedly carinate, and fasciculate on the disc; antenna inserted behind the middle of the rostrum, 
the club ovate or subcylindrical ; rostrum rather slender, about reaching the anterior limit of the meia- 
sternum; femora clavate and sharply dentate; anterior tarsi without projecting hairs; the other 
characters much as in Celosternus compernis and its allies. 
Type, Calosternus dorsalis, Ros. 
Under this genus are included Celosternus dorsalis, Ros., and C. exornatus, Boh., 
both well-known ‘Tropical-American forms, which extend northward to Mexico. 
Lacordaire (Gen. Col. vil. p. 124, nota) has already called attention to the characters 
of C. dorsalis. Ihave not noticed any external sexual marks of distinction in either 
of these two species. 
1. Siron dorsalis. (Tab. XXVI. figg. 28, 28a.) 
Celosternus dorsalis, Ros. in Schéuh. Gen. Cure. iv. p. 225°. 
Hab. Mexico, Toxpam in Vera Cruz (Sai/é); Guaremana, Las Mercedes, Cerro 
Zunil, Mirandilla, San Gerénimo (Champion); Nicaracua, Chontales (Belt, Janson) ; 
Panama, David, Bugaba, Volcan de Chiriqui (Champion).—Braziu!. 
A widely-distributed insect in Tropical America, distinguishable by the ochreous or 
brownish attenuate patch extending down the disc of the prothorax and of the elytra, 
terminating in a short cristate ridge on the second interstice, the third with two 
widely separated fascicles of erect scales. Our specimens vary from 41-8} millim. 
in length. 
2. Siron exornatus. (Tab. XXVI. figg. 29, 29a.) 
Celosternus exornatus, Boh. in Schonh. Gen. Cure. iv. p. 228°. 
Hab. Muxtco, Jalapa (Hoge); Nicaraeua, Chontales (Belt); Panama, Volcan de 
Chiriqui (Champion).—Guvtiana; Braziu}. 
Five specimens of this handsome insect have been obtained from within our limits. 
It is closely related to S. dorsalis, from which it differs in the mottled vestiture of the 
upper surface, the prothorax having a yellowish-white heart-shaped patch on the disc 
behind, and the elytra a similarly-coloured spot on each shoulder. 
COLLABISMUS. 
Collabismus, Schonherr, Gen. Curc. iv. p. 286 (1837) (part.); Lacordaire, Gen. Col. vii. p. 116 
(part. ). 
This genus includes two or more Tropical-American species (C. elitelle and 
C. notulatus, Boh., and perhaps others *), which may be recognized by the following 
* The insect representing C. cluniferus, Boh., in Dr. Sharp’s collection belongs to the ‘ Tylodides,” and 
= Luwenus apicalis, Faust, anted, p. 494. 
