of the Amazon, Valley. 253 



2. Griodioii rhinoceros , n. sp. 



Magnum, parallelogrammicum, vix depressum, fuscuiu, 

 fulvo - griseo - tomentosum ; mandibulis supra medio 

 utrinque cornu valido acuto armatisj thorace transvei'- 

 sim quadrato, supra inaequali, plagis elevatis nonnuUis 

 politis sulcisque rectis et curvatis; elytris subtilissime 

 coriaceiSj vermiculato-rugosis, apice truncatis et utrinque 

 bispinosis ; pedibus robustis, femoribus intermediis et 

 posticis apice bidentatis. 



Long. 2 un. $ . 



Notwitlistandiug the very remarkable armature of the 

 mandibles, this species is evidently a true Criodion, all 

 other parts of structure agreeing with the typical species 

 of the genus. The horn-like processes arise from the 

 upper edge of the organs about the middle, are nearly as 

 long as the mandibles themselves, and incline towards 

 each other, crossing at the apices ; together with the 

 broad corrugate cheeks, they give to the head of the in- 

 sect, viewed in profile, a curious resemblance to that of 

 a Rhinoceros. The thorax is relatively much broader 

 than in other species, and the irregular surface is marked 

 in the middle with grooves forming a large trilobed figure, 

 with the lobes directed towards the head. 



Hab. — River Tapajos. I beat an example out of a tree 

 in the forests near the mouth of the Tapajos, in 1852.* 



Genus Sphallenum, nov. gen. 



This genus is formed for the reception of certain 

 species allied to Criodion, which differ from that group 

 in having the sockets of the intermediate haunches 



* The following is an undescribed species of Criodion, differing in the 

 nearly smooth thorax from the more typical forms : — 



Criodion hirsutum. 



Elongatiim, angustatum, fuscum, fulvo-griseo-hirsutum, pihs thoracis 

 et elytrorum decumbentibus. Caput rugosum, vertice inter oculos tuber- 

 culo elongato. Thorax qnadratum, lateribus paulo rotmidatis et rugoso- 

 tuberculatis, dorse sublaevi, punctis grossis et tubercnlis Iffivibus tribus 

 notato. Elytra creberrine punctulata, apice rotundata, sutura solum 

 spinosa, supra pilis sparsis deciunbentibus vestita. Femora intermedia 

 et postica apice unispinosa, tibtis apice extus valde spinosis. Acetabula 

 intermedia extiis paulo hiantia. 



Long. 1 un. 7 Un. ; lat. elytr. 4^ Un. 



Hah. — Bahia (a Dom. Eeade captum). 



