in the Depths of the Sea. 437 



Paragorgia arborea, our great Pennatulids, Rhizocrinus, Astro- 

 phyton Linckii and A. Lamarckii, Asteronyx, Ophioscolex, 

 Ophiacantha spinulosa, Ctenodiscus, Brisinga, Echinocucumis 

 typica* , Oligotrochus, Terebratula septata and T. cranium, 

 Lima excavata, Limopsis minuta, Lyonsiella, &c. ? 



With so rich a fauna as that with which we are in some 

 degree acquainted on our coast to the depth of 200-300 fatli., 

 and in some cases to 450 fath., which already reckons 427 

 species of nearly all the classes of marine animals } there is 

 plainly yet no sign ivhich indicates any diminution of animal 

 life. This, indeed, also agrees very well with the glimpse of 

 that life which we have lately had through the soundings of 

 Wallich and O. Torell in still greater depths, which show us 

 that even at 1200-1400 fathoms, tolerably highly organized 

 animals live, namely, Echinodermata, Vermes, Mollusks, 

 and Arthropoda. In depths of 3000 fathoms, according to 

 Wallich, no other living animals are found than Protozoa 

 (Rhizopoda, Radiolaria, Spongiadse). It is very probable that 

 animal life, as depth increases little by little, decreases by de- 

 grees, till at last it disappears ; but to take the last-named 

 depth and lay it down as the line of zero, is to build too much 

 on weak premises. It is of consequence in this dark and dif- 

 ficult field, more than elsewhere, to guard against rash conclu- 

 sions. We have on this very subject a warning example in 

 the case of the eminent Ed. Forbes, who having found in the 

 iEgean Sea, at the depth of 230 fathoms, a pair of living spe- 

 cies of Mollusks and Annelids, fell into the great mistake of 

 thinking that animals were there on the verge of disappear- 

 ance, and rather arbitrarily fixed his zero at 300 fathoms. 

 And since Protozoa have been brought up from so considerable 

 a depth as 3000 fathoms, to conclude that no other or more 

 highly organized creatures live there is to conclude too hastily 

 and too much, — especially considering, on the one hand, the 

 limited number of soundings made at such depths, and, on the 

 other, the imperfection of the instruments used. Most cer- 

 tainly many more researches must be made before we dare to 

 hazard a decided opinion as to the point at which animal life 

 necessarily lessens or disappears. 



In conclusion, I will make a remark or two respecting co- 

 lours, the intensity of which is commonly supposed to depend 

 on the action of the sunlight. 



Edward Forbes has remarked (Proc. Royal Soc. vol. i.) 

 that Testacea taken on the British coast from localities under 

 100 fathoms, are entirely white and colourless, even when they 



[* A new species of this genus, E. adversaria, has lately been found by 

 Semper in the Philippine Islands. — A. M. N.] 



