^tuplnjlinidce of the Amazon Valley. 373 



Antenna} yellow, elongate and slender ; 3rd and 4tli 

 joints of abont the same length. Palpi pale yellow. Head 

 broad and short, about as broad as the elytra ; the eyes 

 separated by a broad space, which is distinctly depressed, 

 and closely and coarsely punctured, but in the middle the 

 punctures become sparing, so as to leave an iiTegular longi- 

 tudinal shining space ; on the underside the gena3 are 

 very broad, and densely and coarsely punctured. Thorax 

 much longer than broad, greatly narrower than the elytra, 

 subcylindric ; very slightly rounded at the sides, very 

 densely, coarsely and deeply punctured, so that the inter- 

 stices are rugose and very narrow. Elytra about as long 

 as the thorax, broad, outstanding, the humeral angles 

 strongly marked ; the surface coarsely and deeply punc- 

 tured, the punctures rather close, but the interstices broad 

 and shining. Hind body cylindric and elongate ; the 

 segments coarsely and closely punctured, the 6th towards 

 the extremity sparingly and finely, the 7th obsoletely 

 punctured. Legs yellow, elongate, moderately stout ; the 

 knees reddish. 



Para; a single female. 



Obs. — This species, as well as S. genalis, is remarkable 

 from the broad, very densely and coarsely punctured 

 geuEe. 



19. Stenus tricolor, n. sp. (Sect. II. B, Er.) Elongatus, 

 angustulus, nitidus, viridi-a3neus, abdomine rufo-testaceo, 

 apice abrupte nigro ; antennis rufis, basi cum palpis pedi- 

 busquc flavis. Long. corp. 2\ lin. 



Antennae elongate and slender, pale yellow at the base, 

 darker towards the apex ; paljii pale yellow. Head broad, 

 not excavate, but the middle slightly elevated, and between 

 this and the eye with a small depression on either side ; 

 the antennal tubercles elongate, the punctuation sparing 

 and irregular. Thorax longer than broad, narrower than 

 the elytra, subcylindric, but distinctly broadest in the 

 middle, and the basal portion slightly contracted; shining, 

 rather coarsely and not sparingly punctured, the basal 

 ])ortion Avith a smooth space along the middle. Elytra 

 slightly longer than the thorax, rather narrow and elongate ; 

 the shoulders rectangular and sharply marked; the colour 

 shining-green like the thorax ; the punctuation coarse, 

 moderately close. Hind body elongate, slender and cylin- 

 dric ; reddish, shining ; the basal segment distinctly, the 



