ON DREDGING AMONG THE HEBRIDES. 191 



a corresponding intensity of colour \inder ordinary cii'cumstances, yet the 

 diminution or absence of light in the sea is not necessarily followed by a 

 diminution or absence of colour in marine animals. Those taken from con- 

 siderable depths have frequently vivid colours. The animal of Lima excavata 

 (a comparatively gigantic species), from 300 fathoms, is of the same bright 

 red colour as those of L. Loscombii and L. hians from shaUovs^ water. It has 

 been shown that violet and blue rays of light (and probably actinic rays) 

 penetrate deepest in water. I will not here repeat what I have already 

 published* on this interesting subject; but I may add that all the animals 

 recorded as living at great depths are zoophagous, none of them phyto- 

 phagous. The deep-sea di-edgings of the Swedish Expedition to Spitz- 

 bergen in 1S61 yielded some valuable results. Adjunct-Professor ToreU 

 and Professor Keferstein communicated some short and imperfect notices to 

 the no^.thern journals ; but Professor Loven has lately given us fuller infor- 

 mation, which is published in the Transactions of Scandinavian Naturalists 

 at their ninth meeting held in 1863 1. A Brooke's lead and a ' Bulldog ' 

 machine, with several improvements, were used on this occasion. Depths 

 from 6000 to 8400 feet (1000-1400 fathoms+) were thus explored. The 

 sea- bottom at these depths was covered with a fine greasy-feeling material 

 of a yellow-brownish or grey colour, rich in Diatomacete § and Polythalamia, 

 and nearly devoid of sand. Professor Loven was furnished with the notes of 

 Messrs. Chydenius and Malmgren, made during the expedition, and with all 

 the animals discovered in those great depths. The latter comprised : — Anne- 

 lida, viz. species of Spiochcetopterus and CirratuJus ; Crustacea, viz. a Cuma 

 which appeared to be identical with C. rubicunda, LUljeborg, and an Apseudes ; 

 Mollusca, viz. a Cylichna ; Gephyrea, viz. a fragment of Mijriotroclms RinTci, 

 Steenstrup, and another allied form with large and fewer star-wheels, and of 

 smaller wheels of the Mi/riotrocJws-typc ; a species of Sipunculus resembling 

 8. margaritaceus, Sars ; and, lastly, a sponge, in which were found a Cope- 

 pod or Ostracod, and a fragment of a Cuma resembling C nasica. In the 

 opinion of Loven these animals indicate, so far as can be judged by so small 

 a number, that in the abysses of the glacial seas there lives a fauna which 

 does not greatly differ from that which lives on the same kind of bottom at 

 much less depths. Proceeding upwards to the surface, from 50 or 60 fathoms 

 the regions or zones have a greater variety of animals, even over the same kind 

 of bottom. Taking this into consideration, and also recollecting that in the 

 Antarctic seas, at measui'able depths, there are forms of Mollusca and Crus- 

 tacea which exhibit partly generic, partly almost specific identity with north- 

 em and hyperborean forms, the idea occurs to him that, in depths of 60-80 

 fathoms and thence down to the greatest from which we hitherto know any 

 animal life, at least wherever the bottom is covered with a soft and fine mud 

 or clay, there exists from pole to pole, in all latitudes, a deep-sea fauna of the 

 same general character, many species of which have a very wide distribution. 

 He also thinks it probable that in the vicinity of both poles such a uniform 

 fauna approaches the surface ; while in tropical seas it occupies the depths 

 of the ocean, the coast line there being represented by vast regions of distinct 

 faunas, the circumferences or areas of which are much more limited. The 



* British Conchology, vol. i., Intr. pp. xlviii-1, and vol. ii. Intr. pp. viii-xi. 



t Stockholm, 1805, p. .384. 



X The Swedish foot makes only 974 English foot. The Scandinavian fathom is 6 feet. 



§ This does not quite agree with the accounts of Wallich and Sars, which give 400 

 fathoms as the limit of vegetable life ; but it does not appear that the Diatomacese ob- 

 served by Loven had actually lived on the sea-bottom. They might have been pelagic 

 and floating kinds. 



