StapJu/linidce of the Amazon Vallei/. 357 



rence of this form in South America as well as in Japan 

 renders it highly probable that other links will be found 

 between these two dissimilar genera. I may indeed here 

 express my opinion that the intei'esting genus Ctenomastax, 

 recently described by Kraatz, from Spain, should be placed 

 next EiicBsthetus , and not among the Ptederidce ; indeed, 

 the descriptions and figures of Kraatz and Fauvel appear 

 to point out as generic distinction fi'om Eiicesthetus only 

 a slight difference in the insertion of the antenna. 



1. StencBsthetus Hiatus, n. sp. Castaneo-testaceus, fere 

 glaber, subnitidus, capite, thorace, elytrisque crebre sat 

 fortiter punctatis, abdomine subtilissime punctulato ; tho- 

 race subcordato, elytris hujus longitudine. Long. corp. 

 H lin. 



Antennfe very slender, but with the basal joint stout, it 

 being quite four times as broad, though scarcely so long 

 as, the 2nd ; joints 2 — 8 excessively slender, differing 

 little from one another in length, 9 and 10 very slender, 

 but distinctly broader than the preceding ones, 10th rather 

 longer than 9th. Head short and broad, with the eyes 

 rather broader than the thorax ; near the front with two 

 distant fovese; moderately closely punctured; the punc- 

 tures, when seen under a high power, are umbilicated, as 

 in Sunius, but the interstices are broad, and covered with 

 a very fine, intricate reticulation, which renders the surface 

 nearly opaque ; the eyes very convex, moderately large, 

 coarsely facetted, reaching the broad vertex. Thorax a 

 good deal naiTower than the elytra, rather longer than 

 broad ; the sides a little rounded in front of the middle, 

 narrowed behind the rounded part ; the hind angles nearly 

 right angles, not rounded ; the surface rather coarsely 

 sculptured, with sculpture similar to that of the head, 

 but . the punctures deeper and the interstices narrower ; 

 along the middle of the basal part are traces of two longi- 

 tudinal impressions. Elytra about as long as and rather 

 more coarsely punctured than the thorax. Hind body 

 robust, but with the apical segments very narrow, exces- 

 sively finely and indistinctly punctured, not shining. Legs 

 slender, pale yellow. 



In the male, on the underside, the 4th and 5th seg- 

 ments of the hind body are plicate in the middle, and the 

 elevated part is slightly produced ; the 6th has the hind 

 margin slightly emarginate. 



