210 OMOTOTTJS. 



short, transverse, slightly produced in front : ahovc the labrum is a 

 transverse triangular earination ; immediately above the base of the 

 antennse are two distinct tubercular elevations, occupying almost tho 

 whole of the surface near the eyes (which in 0. quadripes is repre- 

 sented by a depression) : eyes situated at the base of the head, small ; 

 the line of the base is much less distinct than in 0. quadripes : the 

 surface is irregularly and deeply granulated ; black. Thorax quadrate, 

 decidedly broader in proportion to its length than in 0. quadripes ; 

 the anterior angles are much depressed ; the sides marginate, and 

 produced medially into a lateral angle (almost as distinctly denned 

 as the marginated angle in Octogonotes, and very different from the 

 subsinuation of 0. quadripes) ; the surface throughout is very coarsely 

 and unevenly granulated. Scutelhim obscure, triangular, impunctate. 

 Elytra broader than the thorax, robust, punctate-striate, the punc- 

 tures being quite concealed by a very thick and short squamosa 

 pubescence. Antennae- robust, filiform, subincrassatcd towards the 

 apex ; in colour fuscous-black. Legs robust, of a fuscous-black colour 

 throughout (not partly flavous as in 0. quadripes). 



The form of the thorax (quadrate instead of transverse) and the 

 colour of the legs seem to supply good specific distinctions between 

 these closely allied forms ; it is possible, however, that hereafter, by 

 the inspection of a large series of examples, it may be shown that 

 but one single species exists, subject to some considerable variation 

 of form and colour. 



Cayenne. In the collection of the British Htiseum, and in the 

 cabinet of the Rev. H. Clark. 



2. Oniototus quadripes. 

 Chevr. 3IS. 



0. oblongo-ovatus, latus, robustus, impubescens, niger ; capite brevi, 

 granulato ; thorace transverso, ad latera media sid>producto, for- 

 titer granulato; elytris punctato-striatis, subsquamosis ; antennis 

 filiformibus ; pedibus piceis, femoribus et tibiis (ad basin) an- 

 terioribus Jlavis. 



Long. corp. 3| lin., lat. If lin. 



Oblong-ovate, broad, robust, impubescent, black. Head short, 

 depressed at almost right angles to the thorax, and not produced in 

 front ; above the labrum is a transverse triangular plane (the colour 

 of which is more distinctly rufous than the rest of the surface) ; above 

 the base of the antennse and between the eyes is a longitudinal 

 irregular medial depression ; the eyes are situated at the base of the 

 head ; the surface between the eyes and at the base irregularly and 

 unevenly granulated, in colour darkly rufo-fuscous. Thorax trans- 



