Paramphithoe 325 



lateral and post-antennal augies alike sharply outdrawn. Side-plates 1 

 and 3 apically serrate in 4 teeth, plates 2, 5 and 7 each with 2 denticles, 

 4*'' and 5*'' irregularly sculptured below. Eyes round. Maxiila 2, inner plate 

 rather broader than outer (?). Gnathopods 1 and 2 feeble, subequal. Peraeo- 

 pods 3 — 5, 2"^ Joint with 3 acute processes of the bind niargin in peraeo- 

 pod 3, with 4 in peraeopods 4 and 5. Telson longer than breadth at base, 

 tapering, with a triangulär emargination betweeu 2 triangulär apices. Colour 

 unifornily pale reddish yollow. L. 22'o mm (2'^ antenna 23 mm long). 



Arctic Ocean (CTi-eenland). Uepth 5(3 in. 



2. P. hystrix (J. V.. Ross) 1835 Acanthosoma h., (Rieh. Owen in MS.) ,J. C. 

 Ross in: John Ross, App- sec. Voy., nat. Hist. p. 91 t. b f. 4 — 7 | 1838 AnißhitJioe h., 

 Kröyer in: Dan.skeSelsk.Afh.. v.'l p. 259 t. 2 f. 7 | 1859 Paramphithoe h., R. M. 

 Üi'uzelius in: Svenska Ak. Handl., n. ser. u 3 nr. 1 p. 71 | 1877 Acanthozone h., Miers 

 in: Ann. nat. Hist., ser. 4 v. 19 p. 136; f. 20 p. 100 \ 1888 A. h., T. Stebbing in: Rep. 

 Voy. Challenger, «5.29 p. 50, 318, 466 | 1894 A. h., T. Stebbing in: Bijdr Dierk., r. 17 

 p. 29 I 1871 .4. cuspidata (err.?, non Oniscus cuspidatus Lepechin 17801), A. Boeck in: 

 Forh. Selsk. Christian., 1870 p. 184 | 1876 A.c., A. Boeck, Skand. Arkt. Amphip., v.2 

 p. 229 t. 20 f. 3! 1893 A.c., G. O. Sars, Crust. Norway, v.\ p. 370 t. 130 | 1893 A.c. 

 (part.), A. Delhi Valle in: F. Fl. Neapel, f. 20 p. 613 t. 59 f. 25. 



Body nearly cylindric. Peraeon segment 1 with large laminar carinate 

 process completely overarcbiug the head, a smaller subdorsal process on either 

 side, Segments 1 — 7 with 5 processes from transverse ridge of bind margin 

 as in A. buchholzi. Pleon segments 1 — 3 with similar central process, and 

 on either side of it in segments 1 and 2. 4 sharp processes, the 2 upper 

 rauch larger than the 2 lower, in segment 3 two on each side which are 

 subequal, segment 4 with sharp median and postero-lateral processes, segments 5 

 and 6 with acute process at postero-lateral angles but no dorsal process. Head, 

 rostrnm very small, horizontal, lateral corners forming a subtruncate lobe, 

 post-antennal corners sharply outdrawn. 8ide-plates 1 — 3 acutely produced 

 at apex, not serrate, 4**' with 2 acute processes pointing downward, 5^^ 

 with 2 pointing backward, 6*^ and 7*^' with 1 acute process. Eyes prominent, 

 rounded, dark brown (Sars) or white (Bäte). Antenna 1, P* Joint as long as 

 2^^ and 3*^ combiued. with large apical process, flagellum about 3 times as 

 long as peduncle. Antenna 2 much longer, joints of peduncle produced to 

 dentiform projections, ultimate and penultimate joints of peduncle subequal, 

 flagellum nearly 4 times as long as peduncle. Gnathopods 1 and 2 subequal, 

 5*^ Joint slightly shorter than 6*^, 6^^ widening a little distally, palm nearly 

 transverse, finger small. Peraeopods 3 — 5, 2*^ Joint with only 2 acute processes 

 of bind margin. Telson as long as once and a half breadth at base, tapering, 

 slightly (raore than in tigure by Sars 1893) emarginate. Colour light straw- 

 yellow, mottled with brown. L. reaching over 30jnm. 



Arctic Ocean, widely distributed; North -Atlantic (North- America; Norway, 

 Trondhjemsfjord and northward). 



3. P. polyacantha (J.Murdoch) 1885 Acanthozone p., .1. Mnrdoch in: P. U. S. 

 .Mus., i:l p. 520 ] 1893 A. cuspidata (pait.)':', A. Della Valle in: F. Fl. Neapel, v. 20 p. 613. 



Peraeon segment 1, anterior margin raised into a ridge curving for- 

 ward over the head, segments 1 — 5, bind margin raised into a rounded 

 ridge, developing into a median tooth on segment ö. Peraeon segments 6 

 and 7 and pleon segments 1 — 4 having on bind margin broad median tooth 

 pointing backward, largest on pleon segment 3, nearly obsolete on segment 4, 



