84 



In some specimens the armcomb is totally wanting, and 

 the resemblance of such specimens to 0. maculata Ludwig is 

 very great; also the number of tentacle scales at the first pair 

 of pores is variable, and sometimes there may be t\\'0 tentacle 

 scales farther out on the arm; this character is then not to be 

 relied upon either. 1 have, however, never in 0. robusta found 

 the papillae on the adorai side of the innermost tentacle pores 

 uniting with the mouthpapillae, as Ludwig figures it in 0. ma- 

 culata; the latter species therefore must be maintained, though 

 evidently very nearly related to 0. robusta. 



19. Ophiocteu sericeiim (Forbes). 



Lütken: Additamenta. p. 52. — Duncan & Sladen : Op. cit. p. 62. — 

 Bell: Op. cit. p. 113. — Grieg: Op. cit. p. 264. 



Forsblad Fjord, 14 — 3 fathoms and 90 — 50 fath., numerous 

 specimens. — Hurry Inlet, 7 — fath. and 70 fath., several sp. 



— Sabine Island, anchoring place, several sp. — Кар Dalton, 

 9 — И fath., several sp. — Ryders Sund, 3 fath., several sp. — 

 Henry Land, 20 fath., several sp. — Jan Mayen, 50 — 60 fath., 

 several sp. 



20. Opbiopleura borealis. Dan. Kor. 



Danielssen& Koren: Fra den norske Nordhavs-Expedition. Nyt Mag. 

 for ISaturv. 25. 1879. p. 33. — Duncan <fe Sladen: Op. cit. p. 55. — Levin - 

 sen: Op. cit. p. 403. — Grieg: Ophiuroidea; Norske Nordhavs-Exped. p. 3. 



— Grieg: Die Ophiuriden der Arktis, p. 261. 



Hurry Inlet, 50 fath., numerous specimens. — Кар Hope, 

 121 fath., 3 sp. — Off Canning Island, 202 fath., 1 sp. — Кар 

 Tobin, 57 fath., 1 sp. — Forsblad Fjord, 90 — 50 fath., 8 large, 

 7 small sp. — Fleming Inlet, 118 fath., 8 sp. — SE. off Sabine 

 Island, 110 fath., 2 sp. 



According to Danielssen & Koren the disc is covered 

 by a thick skin, which conceals the scaling; they think this so 

 remarkable, that they establish a new family, Ophiopleuridœ, 

 whose main character is that «the disc is clothed with a firm 

 thick skin, through which the scaling is faintly seen». Levinsen 

 (Op. cit. p. 405) has rightly pointed out that the naked skin 



