Mr. Gwyn Jeffreys on Dredging among the Hebrides. 391 



had procured at a depth of 1260 fathoms (7560 feet) in lat. 59° 

 27' N., long. 26° 41' W., about halfway between Cape Farewell 

 and the north-west coast of Ireland, were originally a shallow- 

 water species, but had gradually, and through a long course of 

 generations, accommodated themselves to the abnormal conditions 

 incident on the subsidence of the sea-bed*. The starfishes in 

 question, which he refers to the Ophiocoma granulata of Forbes 

 {Asterias nigra of 0. F. Miiller), appear, however, to belong to 

 a different species, which inhabits deep water. In an important 

 paper by Professor Sars, on the distribution of animal life in the 

 depths of the st:<.f, he states that Ophiocoma nigra (0. granulata, 

 Forbes) is certainly found in shallow water, viz. from 2 to 30 

 fathoms, on the coast of Norway, but never at a greater depth 

 so far as is yet known, and that it does not range north of the firth 

 of Drontheim. He is of opinion that Dr. Wallich^s species is 

 Ophiacantha spinulosa of Miiller and Troschel, a well-known and 

 Groenlandic species, which is not littoral, but rather a deep-water 

 kind, viz. from 20 to 190 fathoms ; and he infers from Wallich's 

 own account that the last-named species, instead of Ophiocoma 

 nigra or granulata, was the one taken by the 'Bulldogs-sounding 

 in 1260 fathoms. Dr.Wallich also adduces his discovery, at a 

 depth of 682 fathoms (4092 feet), in lat. 63° 31' N., long. 13° 

 41' W., of two testaceous Annelids, which he assumed to belong 

 to " known shallow-water forms," as further evidence of an 

 extensive submergence of the North Atlantic sea-bed. These 

 Annelids were named by him Serpula vitrea and Spirorhis nau- 

 tiloides. But Professor Sars disputes their being shallow-water 

 species. The former he identifies with his Serpula polita 

 (== Placostegus tridentatus, Fabricius) ; the latter is referred by 

 Morch J to the Serpula spirorbis of Linne. The one is regarded 

 by Sars as a deep-water and not littoral species, being found on 

 the Norwegian coast in 20 to 300 fathoms; the other has a 

 wide bathy metrical range, from low-water mark to 300 fathoms. 

 I suspect, moreover, that there has been some mistake in the 

 determination of the Spirorbis, and that it belongs to another 

 species than that to which Wallich has assigned it. As to the 

 accuracy of his statement that he procured living starfishes from 

 a depth of 1260 fathoms, under the circumstances which he has 

 described (viz. " convulsively embracing a portion of the sound- 

 ing-line, which had been paid out in excess of the already 

 ascertained depth, and rested for a sufficient period at the bottom 

 to permit of their attaching themselves to it "), no reasonable 



* Loc. cit. p. 41. 



t Vid.-Selsk. Forhandl. 1864: Ilr.Sars, "Bemferkninger overdetdyriske 

 Livs Udbredning i Iluvets Dybder." 



X Naturhist. Tidsskr. 1863: " Revisio critica Serpulidarum." 



