DISCOLORATION OF THE ARCTIC SEAS. 83. 
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 Diatomacee. 
(2.) TRAE these Diatomacee form the brown staining matter of the 
“ rotten ice " of Northern navigators. 
(3.) That these Diatomacee form the food of the Pteropoda, Meduse, 
and Entomostraca, on which the Balena 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 popu- 
lar 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 deter- 
mination of species to lie over to another time. I have to apologize 
to you for introducing so much of another science, foreign to the ob- 
jects 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 bio- 
logy, I know nothing more strange than the curious tale I have un- 
folded: the diatom staining the broad frozen sea, again supporting 
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 ereation,* whose pursuit gives employment to many 
thousand tons of shipping and thousands of seamen, and the import- 
ance 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 ster- 
ling,t depends for its existence on a being so minute that it takes 
* Nilsson, in his *Skandinaviske Fauna,’ vol. i, estimates the full-grown 
B. _mysticetus, at 100 tons or 220,000 Ib. or equal to 88 elephants or 442 white 
TI n 1867 the Meis screw-steamers of Dundee only took two whales, and 
the loss to each steamer was estimated at £5000, and to the town in all at the 
sum I have e given. 
G2 
