HETEKODERES.— ^EOLUS. 359 



One specimen only of this peculiar little species has been received. Allied to 

 H. robustus (Horn), from Arizona, but much smaller and more convex, the elytra 

 relatively shorter and with convex interstices, the thorax narrowed behind and without 

 distinct carina to the hind angles. 



^EOLUS. 



JEolw, Eschscholtz, in Thon's Archiv, ii. 1, p. 33 (1829) ; Candeze, Monogr. Elat. ii. p. 272. 



2Eolus is here retained, following Candeze, for those species of Monocrepidiini 

 with the fourth tarsal joint feebly produced beneath. It is connected on the one 

 side with Monocrepidius and on the other with Drasterius, some of the species 

 being intermediate. Mollis includes a large number of species, most of which are 

 from Tropical America ; 142 have been described, five only of these being from the 

 Old World. The majority of them have well-defined markings on the thorax 

 and elytra, but the markings are often very variable. Thirty species are here 

 enumerated from Mexico or Central America, seventeen of which are described as 

 new. The North-American Monocrepidius (Drasterius) amabilis, Lee, also belongs 

 to it. The genus is not adopted by Leconte and Horn. 



a. Supra-marginal carina of the prothorax gradually approaching the margin 



behind and joining it at the apex of the angle. 

 a'. Elytra emarginate at the apex, the sutural and outer angles mucronate ; 

 antennas with joint 3 twice as long as 2 ; supra-marginal carina of the 

 prothorax extending forwards to the middle and joining the marginal 



carina behind at the apex of the angle Species 1. 



b'. Elytra rounded at the apex ; antennas with joints 2 and 3 equal, or 3 not 

 much longer than 2. 

 a". Supra-marginal carina of the prothorax extending forwards to the 

 middle and joining the marginal carina behind at the apex of the angle ; 



scutellum feebly or moderately convex Species 2-10. 



b". Supra-marginal carina of the prothorax shorter, not extending forwards 

 to the middle. 



a'". Scutellum feebly or moderately convex Species 11-16. 



b" 1 . Scutellum with a conically raised prominence in the middle . . . Species 17-19. 



b. Supra-marginal carina of the prothorax almost or quite parallel with the 



marginal carina, and abbreviated behind ; elytra rounded at the apex ; 



scutellum feebly or moderately convex ; antennse with joints 2 and 3 equal, 



or 3 not much longer than 2. 

 c'. Supra-marginal carina of the prothorax extending forwards to the middle. 



c". Elytra conjointly rounded at the apex Species 20-27. 



d". Elytra separately rounded at the apex Species 28. 



d'. Supra-marginal carina of the prothorax shorter, not extending to the 

 middle. 



e". Elytra not narrowed at the base Species 29. 



/". Elytra narrowed at the base Species 30. 



