Staphyliiiidce of the Amazon Vallei/. 375 



Palpi elongate, very pale yellow. Head with the eyes 

 large, rather smaller than the elytra, distinctly excavate ; 

 at the bottom of the excavation ^ith a smooth, carina-Hke 

 space. Thorax much longer than broad, subcylindric, but 

 distinctly narrowed towards the front, and a little towards 

 the base ; shining brassy, with fine, pale hairs ; coarsely, 

 deeply and rather closely punctured. Elytra qnite as long 

 as the thorax, Avith the shoulders well marked and pro- 

 minent ; coai'sely, deeply and closely punctured, shining 

 brassy, with a fine, pale, scanty pubescence. Hind body 

 cylindrical, not margined, shining, sparingly, moderately 

 coarsely ]3unctured, with a fine, pale, elongate pubescence. 

 Legs yellow, rather long ; 4th joint of tarsi bilobed, the 

 lobes rather long and narrow. 



The male characters are extraordinary: the hind legs 

 are deformed; the femora are incrassate, the lower margin 

 thickened near the middle, abruptly contracted near the 

 base ; the tibire are also thickened, and furnished near the 

 middle with an angular prominence on their inner face, 

 and below this prominence the inner face is partly sliced 

 off; the basal joint of the tarsus is also distinctly dilated. 

 On the underside of the hind body the basal segment has 

 the hind margin thickened in the middle, but much emar- 

 ginate, so as to form a broad notch, Avitli rather prominent 

 edges; the next segment has a smaller but shining notch, 

 the 4th and 5th segments are also shining in the middle, 

 in front of the hind margin ; the 6th is broadly emarginate, 

 and the 7tli is emarginate at the extremity, the emaigination 

 being continued forwards as a narrow, deep fissure. 



Tapajos ; one male, two female individuals. 



22. Stenus Bafesi, n. sp. Plumbeo-niger, breviter 

 albido-pubescens, dense pimctatus ; antennis palpisque tes- 

 taceis, illis apice infuscatis ; pedibus fuscis, tibiarum basi 

 testaceo ; capite coleopteris multo angustiore, bisulcato, 

 crebre punctato ; prothorace macula medio l^vi ; elytris 

 thorace longioribus, dense fortiterque punctatis ; abdo- 

 mine elongato-conico, dense punctato. Long. corp. fere 

 2 lin. 



AntennfB moderately long, and rather stout, dark yellow ; 

 the club, Avhich is long in projiortion to the other part, more 

 obscure. Head rather small, much narrower than the 

 elytra, not excavate, but with a small space on the middle 

 elevated, and a depression on either side of this; rather 



