104 THRASYGCEUS. 



antennis Jilifonnibus, tenuibus, articidis 1-4 rufo-Jiavis, 5-7 

 fuscis, &-W pallide cinereis ; pedibus flavis. 



Long. corp. 3f lin., lat. 2 lin. 



Oblong-oval, broad, robust, subdepressed. Head short, depressed 

 (almost vertical), not produced ; below the base of the antenna? is a 

 transverse triangular glabrous depression ; the surface between the 

 eyes granulated, with two more distinct wart-like prominences ; at 

 the base thickly punctate, black. Thorax transverse, constricted in 

 front ; the anterior angles depressed, hardly extending laterally be- 

 yond the eyes ; the sides marginate ; at the base is a broad shallow 

 medial depression ; the surface subpubescent and finely punctate, 

 flavous, slightly suffused with black towards the apex. Scutellum 

 triangular, black. Elytra robust, somewhat broader than the thorax, 

 with punctures arranged in the form of striae, finely and closely pu- 

 bescent ; black, with four large and two smaller white markings ; 

 the two smaller oval, close to the scutellum between the first and 

 third striae ; of the larger, two (broad and transverse) are situated 

 antemedially between the second and the ninth striae, while two are 

 similarly situated nearer to the apex. Antenna; filiform, attenuated ; 

 first to fourth joints rufo-flavous (on the upper surface of the apex 

 fuscous), fifth to seventh fuscous, eighth to eleventh very pale cine- 

 reous, almost white. Legs flavous throughout ; the apex of the pos- 

 terior femora dark fuscous ; the bladder-like inflation of the posterior 

 claw bright ferrugineous. 



This insect, at first sight, resembles Octogonotes sumptuosus ; it 

 differs, however, in its more robust form, in the deeper and more 

 distinct .punctuation at the back of the head, and by the absence of 

 any tooth-like projection in the margination of the thorax, in the 

 fuscous colour of the scutellum, and in the disposition and colouring 

 of the markings on the elytra, as well as in the great contrast of form 

 of the maxillary palpi. 



A single specimen, captured by Mr. Bates in the Amazon district, 

 is in that gentleman's cabinet. 



2. Thrasygceus exaratus. 



T. oblongo-ovatus, latus, punctato-striatus, nigro-cyaneus ; capite 

 brevi, transversa, super basin antennarum bituberculato, punctata, 

 fulvo-rufo ; thorace transverso, antice attenuato, ad basin tram- 

 verse depresso, sparsim punctata, rufo ; elytris latis, punctato- 

 striatis, nigro-cyaneis ; antennis Jiliformibus, nigris ; pedibus 

 robustis, piceis, femoribus fusco suffusis. 



Long. corp. 4 lin., lat. 2 lin. 



Oblong -ovate, broad, punctate-striate. dark blue,. glabrous. Head 



