EEPOKT ON THE ASTEROIDEA. 



171 



|8. Bathymetrical range: 7 fathoms to 1325 fathoms. 



All the species extend into the Abyssal zone, but none of them are exclu- 

 sively confined to it. 



Greatest range of one species : Ctenodiscus procurator, 40 to 1325 fathoms. 



y. Nature of the Sea-hottom : Ctenodiscus corniculatus is found on variable bottoms ; 

 but usually on mud and soft clay; occasionally hard and shelly. Ctenodiscus 

 australis is found on sand, and on Green sand in 600 fathoms. Ctenodiscus 

 procurator has only been found hitherto on Blue mud. 



Chorological Synopsis of the Species. 



1. Ctenodiscus corniexdatus (Linck), Perrier. 



Astropecten corniculatus, Linck, 1733, De Stellis marinis, p. 27, tab. xxxvi., No. 63. 



Asterias crispata, Retzius, 1805, Dissert, sist. species cognitas Asteriarum, p. 17. 



Asterias polaris, Sabine, 1821, in Parry's Journ. of a Voyage for the Discovery of a N.W. Passage, 



&c, in 1819-20, Append., p. cexxiii., pL i. figs. 2, 3. 

 Asterias arancia, Dewhurst, 1834, Nat. Hist, of the Order Cetacea, &c, p. 283. 

 Astropecten polaris, Gray, 1840, Ann. and Mag. Nat. Hist, vol. vi. p. 180. 

 Ctenodiscus polaris, Miiller and Troschel, 1842, System der Asteriden, pp. 76, 129. 

 Ctenodiscus pygmccus, Miiller and Troschel, 1842, System der Asteriden, pp. 76, 129. 

 Ctenodiscus crispatus, Diiben and Koren, 1846, K. Vet.-Akad. Handl., 1844, p. 253. 

 Anodiscus crispatus (1 Val. M.S.), Perrier, 1869, Ann. Sci. Nat, 5e Ser., t. xii. p. 298. 

 Ctenodiscus corniculatus, Perrier, 1876, Revis. Stell. Mus., p. 380 (Arch, de ZooL exper., t. v. p. 300). 



Localities. — " Porcupine" Expedition : 



Station 82. In the Faeroe Channel. Lat. 60° 0' 0" N., long. 5° 13' 0" W. Depth 312 

 fathoms. Bottom temperature 5°"2 C. ; surface temperature ll c- 2 C. 



Station 57. 1 In the Faeroe Channel. Lat. 60° 14' 0" K, long. 6° 17' 0" W. Depth 632 

 fathoms. Bottom temperature — 0° - 8 C. ; surface temperature 11°*1 C. 



Station 58. 1 In the Faeroe Channel. Lat. 60° 21' 0" N., long. 6° 51' 0" W. Depth 540 

 fathoms. Bottom temperature — 0°"6 C. ; surface temperature 10°'6 C. 



i This occurrence is recorded in Sir Wyville Thomson's Depths of the Sea, but I have not seen a 

 specimen. 



