MONOPLATUS. 17 



differences) it is almost sufficient to render it impossible that one 

 should be constituted merely a variety of the other. 



13. Monoplatus semiviolaceus. 



M. oblongo-ovatus, subparallelus, impubescens, glaber, rufo-testa- 

 ceus ; capite oblique foveolato, ad basin impunctato, antice granu- 

 lato ; thorace transverso, marginato, ad basin transverse foveolato, 

 impunctato ; elytris subtiliter striato-pvnctatis, ad apicem fusco- 

 nigris, ad basin rufo-testaceis ; antennis Jiliformibus, jiavis ; 

 pedibusjiavis. 



<3 Long. corp. 2\ lin., lat. 11 lin. 



Oblong-ovate, subparallel, subrobust, impubescent, glabrous, rufo- 

 testaceous. Head short, transverse, not produced ; labrum broad ; eyes 

 large, prominent, situated at the base of the head : between the eyes 

 an indistinct but well-defined semicircular fovea extends on either 

 side obliquely and upwards to their inner margins (in semichalybeus 

 this fovea is more angulated, and its direction transverse) : the sur- 

 face in front coarsely granulated, at the base impunctate, glabrous. 

 Thorax transverse, broader than the head, the anterior angles de- 

 pressed, the sides marginate : at the base a transverse and well- 

 defined fovea runs parallel to the line of the base, but is abruptly 

 terminated before it reaches the lateral margins by being deflected 

 at right angles towards the basal line ; this transverse fovea is at a 

 greater distance from the basal line than in semichalybeus : the sur- 

 face impunctate, glabrous. Elytra broader than the thorax, sub- 

 parallel, glabrous : under a high power faint punctures may be 

 discerned, arranged in the form of stria? ; these punctures are much 

 more obsolete than in semichalybeus : the apical half of the surface 

 is bright fuscous-black, the line of boundary in each elytron being 

 in a subcircular form (that is, receding towards the apex as it 

 approaches the suture). Antennae filiform, flavous. Legs flavous 

 throughout. 



Cayenne. In the collection of M. Chevrolat. 



The above description (pointing out the angulated transverse fovea 

 in the head, and also punctures on the elytra almost obsolete) suf- 

 ficiently distinguishes this species from semichalybeus. 



14. Monoplatus nigricans. 



M. oblongo-ovatus, subparallelus, subdepressus, impubescens, flavo- 

 rufus ; capite brevi, inter oculos minute transverse foveolato, im- 

 punctato ; thorace transverso, impunctato, ad basin foveolato ; 



