SOUTHWARD 69 
quite a number of occasions, and it is hard to account for 
such vagaries on other grounds than that a sick animal will 
go any distance to get away from its companions’’! (and 
perhaps it should be added from its enemies). 
Often the under sides of the floes were coloured a 
peculiar yellow. This coloration is caused by minute uni- 
cellular plants called diatoms. The floating life of the Ant- 
arctic is most dense. “ Diatoms were so abundant in parts 
of the Ross Sea, that a large plankton net (18 meshes to an 
inch) became choked in a few minutes with them and other 
members of the Phytoplankton. It is extremely probable 
that in such localities whales feed upon the plants as well 
as the animals of the plankton.” I do not know to what 
extent these open waters are frequented by whales during 
the winter, but in the summer months they are full of 
them, right down to the fringe of the continent. Most 
common of all is the kind of sea-wolf known as the Killer 
Whale, who measures 30 feet long. He hunts in packs up 
to at least a hundred strong, and as we now know, he does 
not confine his attacks to seal and other whales, but will 
also hunt man, though perhaps he mistakes him for a 
seal. This whale is a toothed beast and a flesh-eater, and 
is more properly a dolphin. But it seems that there are at 
least five or six other kinds of whales, some of which do 
not penetrate south of the pack, while others cruise in 
large numbers right up to the edge of the fast ice. They 
feed upon the minute surface life of these seas, and large 
numbers of them were seen not only by the Terra Nova 
on her various cruises, but also by the shore parties in the 
waters of McMurdo Sound. In both Wilson and Lillie 
we had skilled whale observers, and their work has gone 
far to elucidate the still obscure questions of whale dis- 
tribution in the South. 
The pack-ice offers excellent opportunities for the iden- 
tification of whales, because their movements are more re- 
stricted than in the open ocean. In order to identify, the 
observer generally has only the blow, and then the shape of 
1 Discovery Natural History Report, Zoology, vol. ii. part i., by E. A. Wilson. 
2 Terra Nova Natural History Report, Cetacea, vol. i. No. 3, p. 111, by Lillie. 
