new Species 0/ Histeridse. 141 



Plcestus planulus, Lew. Ent. M. M. xvi. p. 76 (1879). 



Oblongus, Bubconvexus, niger, nitidus ; fronte stria fere obsoleta ; 

 pronoto stria marginali antice interrupta ; elytris striis dorsalibus 

 evanescentibus ; prosterno laevi, inter coxas bistriato. 



L. 11-13 mill. 



Oblong, rather convex, black and sliiaing ; tlie head, 

 frontal stria indicated by a few punctures ; the thorax, the 

 marginal stria is interrupted anteriorly after passing the eyes, 

 the lateral stria is not very deep and is parallel to the mar- 

 ginal stria, it terminates behind the anterior angle in a small 

 rugose triangular impression ; the elytra, strise, outer humeral 

 complete, inner apical and short, dorsal are apical and evan- 

 escent anteriorly, the first is longest and most distinct ; the 

 pygidia are evenly and coarsely punctured ; the prosternum, 

 anterior lobe smooth, keel bistriate, strias parallel to each 

 before the coxae and sometimes joining in front. 



In one example in eight the first dorsal stria is fine and 

 complete. 



Hab. Nicobar and Andaman Islands {Roepstorff) . 



Plcesius IcBvis, Lew. Eut. M. M. xvi. p. 76 (1879). 



Oblongo-ovalis, subconvexus, niger, nitidus ; fronte stria inter- 

 rupta ; pronoto stria marginali integra, lateral! valide impressa, 

 medio sinuata iuterstitio paulo lato ; elytris striis 1 integra, 

 2-3 brevibus, punctatis ; propygidio in medio subtiliter punctato ; 

 prosterno impunctato, bistriato ; mesosterno profunde marginato. 



L. 11-13 mill. 



Oblong-oval, rather convex, black and shining ; the head, 

 the labrum is transverse and very narrow, frontal stria bi- 

 arcuate and well divided in the middle ; the thorax, marginal 

 stria complete, lateral deep and sinuous in the middle, and it 

 does not widen out after passing the anterior angle; the 

 elytra, stria3, outer subhumeral complete, inner apical and 

 dimidiate, 1 dorsal fine and complete, 2-3 very short, apical, 

 and more or less distinct ; the propygidium is biimpressed, 

 not closely punctured, points smallest and most feeble in the 

 median area; the pygidium is evenly and wholly punctured; 

 the prosternum, anterior lobe with irregular punctures, which 

 occupy only the central area, bistriate between the coxae ; 

 the mesosternum is anteriorly margined with a conspicuously 

 strong and deep stria. 



This species and P. Icevigatus, Mars., are the only species 

 of the genus with a marginate mesosternum. P. eUipHcus, 



