254 Acanthostepheia, Aceroides 



1. A. malmgreni (Goes) 1866 Amphithonotus m., Goes in: Öfv. Ak. Förh., 

 r. 22 p. 526 t. 39 f. 17 | 1871 Acanthostepheia m., A. Boeck in: Forh. Selsk. Christian., 

 1870 p. 163 I 1876 A. m., A. Boeck, Skand. Arkt. Amphip., v. 2 p. 263 | 1894 A. m., 

 T. Stebbing in: Bijdr. Dierk., v.ll p. 24 ] 1887 A. malmgrenii, H.J.Hansen in: \'id. 

 Meddel., ser. 4 t\ 9 p. 104 [ 1893 Oediceros m. (pari), A, DellaValle in: F. Fl. Xeapel. 

 V. 20 p. 544 t. 58 f. 55. 



Head, rostrum not always reacliing end of 1^* Joint of antenna 1, 

 lateral angies acute, carina not quite extending to hind margin. Peraeon 

 Segments strongly ridged transversel}^ carina rudimentaiy on first 5, on 7^'^ 

 and on pleon Segments 1^ — 4 longitudinally bidentate. Postero-lateral angies of 

 peraeon segments 5 — 7 and pleon segments 1 — 3 acute, intermediate ridges on 

 the latter. Side-plates 5 and 6 with 2 acute lobes, 7^^ with one acute lobe. Eyes 

 reniform, diverging backward from base of rostrum. Antenna 1, 1*** Joint very 

 long, 2^ rather shorter, flagellum subequal to peduncle, 40-jointed. Antenna 2, 

 ultimate and penultimate joints of peduncle long, subequal. Gnathopod 2, process 

 of 5**1 Joint rather longer and narrower, and 6*^ Joint rather longer than in 

 gnathopod 1. Peraeopods 1—5 not very hirsute, finger shorter than 6*^ Joint in 

 peraeopods 1 and 2, longer than it in peraeopods 3 and 4. Peraeopod 5, 2*^ Joint 

 longitudinally carinate, 5* and 6*^ joints much longer than 4*'^ 5*^ a little 

 longer than 6*^. üropod 3, peduncle carinate, decidedly louger than rami. 

 Telson little longer than broad, distally a little emarginate. Colour dull 

 yellow, dorsally red. L. sometimes 45 mm. 



Arctic Ocean (Spitzbergen, Franz Joseph Land, Siberia, Barents Sea, Kara Sea, 

 Greenland). Depth 10— 300 m. 



2. A. pulehra Miers 1881 A.p., Miers in: Ann. nat. Hist., ser. 5 v.7 p. 47 t. 7 

 f. 1,2 I 1894 A.p., T. Stebbing in: Bijdr. Dierk., «.17 p. 25 ] 1882 Acanthostephia 

 malmgreni (err., non Amphithonotus m. Goes 1866!), Stuxberg in: Vega-Exp., v.l p. 724 

 f. (no description) ] 1893 Oediceros malmgrenii (part.), A. DellaValle in: F. Fl. Neapel 

 V. 20 p. 544. 



Head, rostrum reaching fully to or beyond apex of 1^* Joint of antenna 1, 

 lateral angies acute, but almost quadrate, carina not quite extending to 

 hind margin. Ridges and carina of peraeon and pleon similar to those in 

 A. malmgreni, but far less strongly developed, carina of pleon segment 3 

 scarcely bidentate. Postero-lateral angies of peraeon segments 5—7 and 

 pleon segments 1 — 3 rounded. Side-plates 5 and 6 with rounded lobes, the 

 hinder produced much below the front one. Eyes oval, parallel. Antenna 1 

 shorter than in A. malmgreni, 2*^ Joint considerably shorter than 1^*, flagellum 

 about 20-jointed. Antenna 2, ultimate Joint of peduncle considerably longer than 

 penultimate. Peraeopods 1 — 4, finger not longer than 6*'^ Joint. Peraeopod 5, 

 2'^ Joint not distinctly carinate, 5**^ Joint longer than 4*^ 6*^ longer than 5*^. 

 üropod 3, rarai nearly as long as peduncle. Telson as in A. malmgreni. 

 L. 37 mm. 



Arctic Ocean (Franz Joseph Land, Siberia). Depth 6 — 192 m. 



A. behringiensis (Lockington) 1S77 Oedicerusb., Lockington in: P. Calif. Ac, 

 v.7 p. 47 1 1893 0. b., A. DellaValle in: F. Fl. Neapel, r 20 p. 556. 



Perhaps identical with A. pulehra. L. about 32 mm. 



North of Behring Strait (West Alaska). 



14. Gen. Aceroides 0. Sars 



1892 Aceroides, Aceropsis (Sp. un.: A. laiipes) (non Aceropsis Stuxberg 1880, 

 nom. nud.), G. 0. Sars, Crust. Norway, v. 1 p. 340. 



