84 ARESCUS. 



Var. A. Frontis thoracisquc maciilis obsoletis. 



Chelobasis bicolor, Gray, Griffith Anim. Kingd. Lis. vol. ii. p. 100. 

 pi. 07. f. 4. 



Var. B. Elytrorum apice rufo-fulvo, tibiis extrorsum tareisque 



nigris. 

 Var. C. Coq^ore nifo, cffiteris ut in prsecedentibus. 



Arescus variabilis, Guer. Icon, chi Regne Anim. Texte, p. 268. 



Var. D. Corpore rufo ; thoracis punctis duobus nigris ; elytri.s nigris, 

 basi apiceque ruiis. 

 Arescus variabilis, Guer. Icon, du Regne Anim. Texte, p. 268. 



Var. E. Corpore rufo ; elytris totis nigris. 

 Long., male 5-6, female Q-Q^ lin. 



Hah. Cayenne ; Ega, Upper Amazons ; Peru. 



British Museum, and collections of W. W. Saunders, Esq., E. 

 Sheppard, Esq., M. Deyrollo, and J. S. Baly. 



This species differs from the former in the following characters : — 

 The frontal horn (Tab. III. fig. 40) in the male gradually decreases 

 in -width to its truncate apex ; head between the eyes deeply im- 

 pressed by a large concave fovea, which, instead of being opaque and 

 rugose as in the last species, is smooth and shining ; thorax with its 

 sides straighter, and without the marginal tooth, the surface less 

 deeply punctured ; elytra without an elevated ridge behind, theii' 

 apex less deeply emarginate. The femaJe is veiy closely alhed to 

 that of Arescus histrio ; it may, however, be distinguished by the 

 broader truncate frontal horn, the smooth frontal depression, and also 

 by the narrower, nearly quadrate thorax ; the apex of the elytra is 

 also entire, or obsoletely sinuate, the apical tooth being very small. 

 The variations of coLiur, although remarkable, are less than in 

 the preceding insect ; the antennae are black at their apex only, 

 whilst the legs for the most part, together with the under siu-faee of 

 the body, are entirely yellow. 



5. Arescus perplexus, n. sp. 



A. elongatus, niger, nitidiis ; eapite infra, pectore abdomineque ob- 

 scure fulvis ; elytris convexis, utrisque apice angulato-productis, 

 punctato-striatis, fuhis ; margine, sutura postice, puncto humerali 

 fasciisque duabiis, extrorsum abbreviatis, nigris. 



Long. 5^ hu. 



A. antennse and head above, black ; frontal horn (Tab. III. fig. 41) 

 broad, scarcely narrowed towards the apex, truncate ; head be- 

 tween the eyes with a deep concave excavation, the sm-face of 

 which is smooth and shining, with a few indistinct imjn'essions. 

 Thorax black, transverse-quadrate ; sides parallc 1. ncai-lj- straight. 



