74 



'Remarks. - This new genus is nearly related to the genus Orchomene, 

 though differing materially by the epistome being not at all prominent, by the 

 very powerful structure of the anterior gnathopoda, and by the much fuller 

 development of the last pair of uropoda and of the telson, finally by the un- 

 armed last pair of epimeral plates of the metasome. In the structure of the 

 oral parts it comes somewhat nearer to the genus Orchomenetta. Besides the northern 

 species described in the sequel, 2 of the Challenger species referred by the Rev. 

 Mr. Stebbing to the genus Orchomene, viz., 0. musculosus and O.abyssorwm,-, evidently 

 belong to the present genus and perhaps also his 3rd, species, 0. excavatus. 



28. Orchomenopsis obtusa, G. 0. Sars, n. sp. 



(PI. 26, fig, 2.) 



Body moderately slender with broadly rounded back. Cephalon about 

 as long as the 1st segment of mesosome, lateral corners but slightly projecting 

 and broadly rounded. Anterior coxal plates about twice as deep as the body ; 

 1st pair gradually widening below; 4th pair distinctly emarginated posteriorly 

 and forming below the emargination an obtuse projecting lobe; 5th pair fully 

 as deep as broad. Last pair of epimeral plates of metasome not at all pro- 

 jecting at the infero-lateral corners, the edge forming an even uninterrupted 

 curve. First segment of urosome deeply impressed at the base dorsally and 

 forming below the depression a rounded carina. Eyes rather large, irregularly 

 oval, pigment ligth red. Superior antennae with the 1st joint of the peduncle 

 very large and thick; flagellum of moderate length, 10-articulate, 1st joint 

 large, about as long as the 5 succeeding joints combined; accessory appendage 

 about half the length of the fiagellum and 5-articulate, 1st joint as long as 

 the remainder part of the appendage. Inferior antennae rather slender, exceed- 

 ing the superior by about half their length; flagellum composed of about 18 

 articulations. Anterior gnathopoda very strong, propodos twice the length of 

 the carpus and but very slightly tapering to the transversely truncated ex- 

 tremity, carpus exhibiting below a rounded projecting lobe. Posterior gnatho- 

 poda with the carpus rather broad, bulging out interiorly, propodos about 

 half its length, widening distally, with the upper edge curved,, the lower 

 straight. Pereiopoda rather elongated but powerful in structure, basal joint 

 of the 3 posterior pairs much shorter than the remainder part of the leg. 

 Last pair of uropoda with the inner ramus very little shorter than the outer ; 

 terminal joint of the latter very small. Telson about twice as long as broad 

 at the base, regularly tapering distally, with 4 or 5 pairs of dorsal denticles 

 near the edges and 2 other pairs inside the others; cleft extending somewhat 



