256 Mr. C. J. Gahan on Longicorn CoUoptera 



Plocederus chloropterus of Clievrolat. Murray's description of 

 it is very complete. It will be sufficient therefore to point 

 out the differences between it and other allied and very 

 similar species. 



From viridipenmsj Hope, and from chloropterus, Chevr., it 

 is distinguished by the very close punctulation of the basal 

 half or third of the elytra ; from chloropterus, Chevr., it is 

 fmther distinguished by the oblique lines or grooves forming 

 a '' crown-shaped " impression on the disk of the prothorax. 



In P. chloropterus, Chevr., the prothorax is almost regularly 

 transversely wrinkled above and the ridges are not interrupted 

 by oblique impressions on the disk. The elytra, though 

 more strongly punctulate towards the base, have not the 

 punctures much more thickly spread on this region than 

 towards the apex. 



In P. viridipennis , Hope, the sculpturing of the prothorax 

 is almost exactly like that of basalts ; the oblique lines are, 

 however, somewhat more distinct and form a W-shaped 

 impression on the disk. The elytra may be described as 

 somewhat sparsely punctulate, with the punctures evenly 

 spread over the whole surface and diminishing in size to the 

 apex. The prosternal process is provided posteriorly with a 

 more or less distinct median tubercle. 



It is difficult, from Hope's short diagnosis, to identify his 

 species with certainty. The characters just given are taken 

 from a species from Sierra Leone which Adam White had 

 labelled viridipennis^ Hope, and which agrees with Hope's 

 description. 



Plocederus gdbonicus, sp. n. 



Niger ; elytris metallico-viridis, fusco tinctis ; prothorace supra 

 fortiter transversim rugoso, rugis anticis recte transversis, rugis 

 pone medium sinuatis ; elytris subtilissime griseo-pubescentibus, 

 versus basin confertim punctulatis, versus apicemminutissime sat 

 denseque punctulatis, apicibus truncatis, angulis dentatis ; an- 

 tennis ( $ ) corpora vix excedentibus, nigris (scape badio excepto), 

 articulis a quinto ad decimum apice interne denticulato-productis ; 

 pedibus femoribus (basi apiceque exceptis) rufo-testaccis, tibiis 

 basi nigris ; processu prosterni medio postice tuberculato. 



Long. 30, lat. 9| mm. 



Hah. Gaboon (W. Africa), 



The strong and almost quite regular transverse wrinkling 

 of the prothorax uninterrupted by any oblique impressions on 

 the disk, the very close punctulation of the basal part of the 

 elytra, and the median tubercle to the prosternal process will 



