416 INSECTA. 



posteriorly on the head; front of the thorax cut obliquely, with 

 three teeth or tubercles on the elevated portion posterior to the 

 section; elytra smooth. Found, together with its larva, in tan. 

 O. silenus; G. silenus, Fab.; Oliv., Col., I, 3, viii, 62, a c 

 Smaller than the nasicornis; of a lighter but similar hue; a little 

 recurved and pointed horn on the head of the male; a deep ex- 

 cavation in the middle of the thorax; the last joint of the two 

 anterior tarsi inflated, and with two very unequal hooks; elytra 

 finely and irregularly punctured(l). In 



Agacephala, Manh. 



The anterior legs, at least in the males, are longer than the suc- 

 ceeding ones, and the four posterior tibiae are slender or not thick, 

 almost cylindrical, slightly dilated at the extremity, and without 

 deep lateral incisures or emarginations. 



The labrum is entirely concealed. The terminal lobe of the max- 

 illae is simply pilose. The antennae consist of ten joints; the suppu- 

 tation of their number in the Encyc. Method., article Scarabees, 

 which amounts to but nine, is erroneous. 



I know two species, both from Brazil(2). 



Sometimes the maxillae, usually corneous or scaly, are more or 

 less dentated. In 



ScarabjEus proper, Geotrupes, Fab. 



The body is thick and convex, and the outer side of the mandibles 

 sinuous or dentated. 



The equatorial countries of both hemispheres produce very 

 remarkable species of this subgenus. 



$. Hercules, L; Oliv., Col. I, 3, 1, xxiii, 1. Five inches 

 long; black; elytra greenish-grey mottled with black; a re- 

 curved and dentated horn on the head of the male, and a second 

 one, long, projecting and pilose beneath, with a tooth on each 



(1) Add the Geotrupes, boas, rhinocerus, stentnr, &c. of Fabricius. 



The genus Orphnus, Mac Leay, established on the G. bicolor of Fabricius, does 

 not differ from the preceding. The anterior margin of the labrum is salient or 

 exposed. The maxillte are terminated by a bundle of spinuliform cilia, arcuated 

 outwards, with a crustaceous triangular lobe. The antennal club is nearly globu- 

 lar. His genus Dasygnathus, placed by him in his family of the Dynastides, is 

 unknown to us, but we presume, from the description of its characters, that it ap- 

 proaches the preceding and following genus. 



(2) The Mgeon of Fabricius is perhaps congeneric. 



