241 BROWNj ON DISCOLORATION OF THE ARCTIC SEAS. 



is concerned, I was forestalled by Dr. Sutherland (Appendix 

 to 'Penny's Voyage/ cxcviii, and vol. i, pp. 91, 96). This 

 gives me an opportunity of remarking that thovigh one 

 diatom, as I have remarked, predominates, yet vast multi- 

 tudes are there of many different species, and even protozoa 

 are included; for though Dr. Sutherland expressly states 

 that this brown slimy mass was principally composed of the 

 moniliform diatom spoken of, yet Professor Dickie (noAv of 

 Aberdeen) found in it also Grammonema Furgensii, Ag., 

 Pleurosigma Thur'ingica, Kg., P. fasciola, Triceratiuni strio- 

 latuni, Naviculffi, Surirellse, &c. Is it, therefore, carrying 

 the doctrine of final causes too far to say that these diatoms 

 jilay their part in rendering the frozen north accessible to the 

 bold whalemen, as I shall presently show they do, in furnish- 

 ing subsistence to the giant quarry which leads them 

 thither ? 



I have spoken of the discoloured portions of the Arctic 

 Sea as abounding in animal life, and that this life was no- 

 where so abundant as in these dark spaces which owe this 

 hue to Diatomaceac. 



These animals are principally various species of Beroidse, 

 and other Steganophthalmous Medusae ; Entomostraca, con- 

 sisting chiefly of Arpacticus Kronii, A. CheUfer and Ceto- 

 chilus articus, septentrionalis ; and pteroj^odous mollusca, 

 the chief of which is the well-known Clio borealis, though I 

 think it j^roper to remark that this species does not contribute 

 to the whales' food nearly so much as we have been taught 

 to suppose. The discolored sea is sometimes perfectly thick 

 with the swarms of these animals, and then it is that the 

 whaler's heart gets glad as visions of " size whales" and " oil 

 money" rise up before him, for it is on these minute animals 

 that the most gigantic of all known beings solely subsists. 

 What, however, was my admiration (it Avas scarcely sur- 

 prise) to find, on examining microscopically the alimentary 

 canals of these animals, that the contents consisted entirely 

 of the Diatomacese which give the sable hue to portions of the 

 Northern Sea in Avhich these animals are principally found ! 

 It thus api^ears that, in the strange cycle of nature, the 

 '^ whales' food" is dependent upon this diatom ! I subse- 

 quently found (though the observation is not neAv) that the 

 alimentary canals of most of the smaller INIollusca, Echino- 

 dermata, &c., Avere also full of these Diatomacere. I also 

 made an obserA'ation Avhich is confirmatory of what I have 

 advanced regarding the probability of these minute organisms 

 giving off en masse a certain degree of heat, though in the 

 individuals inappreciable to the most delicate of our instru- 



