DISCOLORATION OF THE ARCTIC SEAS. 317 



clearly into the dark waters of that frozen sea he knew and loved 

 so well. 



At the same time I believe that I am justified in concluding 

 that we have now arrived at the following conclusions from 

 perfectly sound data, viz. : — 



1. That the discoloration of the Arctic Sea is due not to animal 

 life, but to DlatomacecB. 



2. That these DiatomacecB form the brown staining matter of the 

 " rotten ice " of Northern navigators. 



3. That these Diatomacece form the food of the Pteropoda^ 

 Medusce, and Entomostraca, on which the BalcBna mysticetus 

 subsists. 



I have brought home abundant specimens of the Diatomaceous 

 masses which I have so frequently referred to in this paper, and I 

 am now engaged in distributing them to competent students of this 

 order, so that the exact species may be determined ; but as these 

 take a long time to be examined (more especially as Diatoms do not 

 seem so popular a study as they were a few years ago), I have 

 thought it proper to bring the more important general results of 

 my investigations before you at this time, and to allow the less 

 interesting subject of the determination of species* to lie over to 

 another time. I have to apologise to you for introducing so much 

 of another science, foreign to the objects of the Society, into this 

 paper ; but when the lower orders of plants are concerned, we are 

 so near to the boundaries of the animal world that to cross now 

 and then over the shadowy march is allowable, if not impossible to 

 be avoided. 



Finally, you will allow me to remark that, in all the annals of 

 biology, I know nothing stranger than the curious tale I have 

 unfolded : f the Diatom staining the broad frozen sea, again sup- 

 porting myriads of living beings which crowd there to feed on it, 

 and these again supporting the huge Whale, — so completing the 

 wonderful cycle of life. Thus it is no stretch of the imagination to 

 say that the greatest animal in creation, J whose pursuit gives em- 

 ployment to many thousand tons of shipping and thousands of sea- 

 men, and the importance of which is commercially so great that its 

 failure for one season was estimated for one Scottish port alone at 

 a loss of 100,000/. sterling, § depends for its existence on a being 

 so minute that it takes thousands to be massed together before they 

 are visible to the naked eye, and, though thousands of ships for 

 hundreds of years sailed the Arctic, unknown to the men who were 



* The species principally causing the discoloration is apparently Melosira 

 arctica. 



f The foregoing ohservations on the Discoloration of the Arctic Sea have 

 been confirmed by the German Expedition in the Spitzbergen Sea, under 

 Koldevray ; by that to Greenland, conducted by Professor Nordenskiold. 



X Nilsson, in his " Skandinavisk Fauna," vol i., p. 643, estimates the full- 

 grown B. mysticetus at 100 tons or 220,000 lbs., or equal to 88 elephants or 

 440 white bears. 



§ In 1867 the twelve screw steamers of Dundee only took two Whales, and 

 the loss to each steamer was estimated at 5,000/., and to the town in all at the 

 sum I have given. 



