Euonvx 19 



9. Gen, Euonyx Norm. 



1867 Euonyx (Sp. un.: E. chelatus), A. M. Norman in: ßep. Brit. Ass., Meet. 36 

 p. 197, 202 I 1888 E., T. Stebbing in: Rep. Voy. Chal lenger, ».29 p. 668 ] 1891 E., 

 G. O. Sars, Crust. Norway, f. 1 ]). 116 i 1893 E., A. Della Valle in: F. Fl. Neapel, v. 20 

 p. 841 I 1876 Leptocheki (Sp. un.: Opis leptochela) (non Stimpson 1860, Decapoda!), 

 A. Boeck. Skand. Arkt. Araphip., v. 2 p. 190. 



Side-plate 1 small, partly concealed by 2<^. Mouth-parts differing in tlie 

 2 species. Mandibles with cutting edge almost simple, molar weak or obsolete, 

 palp central or subcentral. Maxiila 1, inner plate not large, outer plate broad, 

 obliquely truncate, palp normal. Maxilla 2, inner plate tbe shorter, obliquely 

 truncate. Maxillipeds. 2*^ Joint of palp reacbing beyond the outer plates. 

 Gnathopods 1 and 2 slender. 3*^ Joint elongate; gnathopod 1 chelate, gnatho- 

 pod 2 subchelate. üropod 3, rami lanceolate, the outer with a small second 

 Joint. Telsou oblong, deeply cleft. 



2 species. 



Synopsis of species: 



Gnathopod 1, Sth and 6tli joints subequal . • I.E. chelatus . . p. 19 



Gnathopod 1, 5th joint mach shorter than ö^h 2. E. normani . . p. 19 



1. E. ehelatus Norm. 1867 E. c, A.M.Norman in: ßep. Brit. Ass., Meet. 36 

 p. 197, 202 I 1888 E. c, T. Stebbing in: Rep. Voy. Challenger, ».29 p. 673 | 1891 E. c, 

 G. O. Sars, Crust. Norway, v. 1 ]). 117 t. 40 f. 1 1 1893 E. c„ A. Della Valle in: F. Fl. 

 Neapel, f. 20 p. 842 | 1868 Opis leptochela, Bäte & Westwood, Brit. sess. (Vust., r. 2 

 [}. 501 \ 1876 0. l, Leptochela, A. Boeck, Skand. Arkt. Ampliip., v. 2 p. 190. 



rieon Segment 3, postero-lateral angles produced to a short bluut 

 point; Segment 4 with dorsal depression followed by high compressed hump. 

 Eyes a constricted oval, chalky white. Antenna 1 large, P' Joint concftve 

 above; flagellumtwicelength of peduncle, withlOjoiuts, 1*** very large; accessory 

 flagellum o-jointed. Antenna 2 twice length of antenna 1. ultimate and pen- 

 ultimate joints of peduncle equal, flagellum 22-jointed. Mandible with molar 

 obsolete, palp on distal side of centre. Maxilla 1, inner plate with several 

 apical setae. Maxillipeds, outer plates rather small with slender setae on the 

 margin, but no spine-teeth. Gnathopod 1 with few setules, 3*^ Joint longer 

 than 5*** or 6**^, 6*^ with bind margin straight, the closely adjacent finger 

 and thumb forming a chela of about ^'g length of the hand. Gnathopod 2 

 longer and stronger than gnathopod 1, 6*^ Joint about Va length of 5*^ 

 distally widened, palm concave, 7^^^ Joint strong and curved. Peraeopods 3 — 5, 

 2'^ Joint not very large, rounded, 4*^^ much expanded. üropod 3 with the 

 rami unarmed, the inner reaching 2*^ Joint of outer. Telson without spinules, 

 oblong, cleft much beyond the middle, apices blunt. Colour whitish tinged 

 with yellow. L. o 10 mm. 



Arctic ücean, North-Atlantic and Irish Sea (Finmark, Trondhjemsfjord, Hebrides, 

 Isle of Man). Depth 95—280 m. 



2. E. normani Stebb. 1888 E. n., T. Stebbing in: Rep. Voy. Challenger, v.29 

 p. 669 t. 19. 



Pleon Segment 3, postero-lateral angles blunt; segment 4 a little raised 

 behind the dorsal depression. Eyes indistinct, narrowly oval. Antenna 1, 

 1^* Joint stout, not concave above; flagellum more than twice length of 

 peduncle, with 29 joints, 1^* very large; accessory flagellum 9-jointed. Antenna 2, 



