137 



Distribution. — Holland (Slabber), British Isles (Sp. Bate), Kattegat 

 (Bovallius); coast of France (Chevreux); ? east coast of North America 

 (Say). 



Gen. f). Urothoe, Dana, 1852. 

 Syn: Egidia Costa. 

 » Sulcator, Sp. Bate (ex parte). 



BocU- very short and thick, with the coxal plates of moderate size. 

 Cephalon rather large and broad, slightly produced in front, and forming on 

 each side, behind the insertion of the antennae, a triangular detlexed lol)e, 

 lateral corners very slight. Metasome and urosome normally developed. 

 Superior antennae similar in the 2 sexes, very slender, joints of the peduncle 

 elongate and nearly cylindric in form, the last 2 generally bent in an elljow- 

 shaped manner; Hagellum much shorter than the peduncle; accessory appen- 

 dage small, but distinctly developed. Inferior antennae in female scarcely 

 longer than the superior, and generally retlexed along the sides of the ceplialon, 

 the 2 oirter joints of the peduncle coarsely spinous on the exterior side, 

 Hagellum only composed of a very restricted number of articulations ; those 

 of male nearly attaining the length of the body, last joint of the peduncle 

 provided anteriorly with a series of ver3' large calceolae ; flagellum very 

 slender aiul filiform, likewise provided with distinct though much smaller 

 calceolae. Mandibles unusually strong, cutting part scarcely denticulate, molar 

 expansion large and protruding, no spines between either; palp comparatively 

 small and narrow. First pair of maxillae rather feeble, masticatory lobe 

 nai-rowly truncated at the tip, basal lobe very narrow, palp comparatively 

 small, with the terminal joint scarcely larger than the basal, and not at all 

 expanded, nor dentate. Second pair of maxillae of normal structure, fully as 

 large as the 1st pair, outer lobe somewhat larger than the inner. Maxillipeds 

 of moderate size, masticatory lobe not very large, and spinous on the inner 

 edge, palp well developed, penultimate joint strongly con.stricted at the base, 

 and gradually dilated distally, nearly club-shaped, dactylus slender and feeble, 

 (inathopoda almost exactly alike in structure, rather feeble, subcheliform, 

 propodos much smaller than the carpus and triangular in form. All pereio- 

 poda having well developed dactyli; antepenultimate pair somewhat unlike 

 the 2 posterior pairs, basal joint not very large, the outer joints more or 

 less expanded, and provided with long ciliated setae and transverse rows of 

 spines; the 2 last pair considerably more slender, with the basal jdiiit land 

 uarl}' expanded, penultimate pair the longest. Second pair nf uropoda very 



18 a — Crustacea. 



