CHAPTER II 



NORTHERN REGIONS 



Arctic seas. 



Respondinp: to the force of the earth's rotation, the vast mass of polar pack-ice drifts from 

 east to west as it moves round the northern world. Frozen near the New Siberian Islands not 

 far from the pole, it enters the North Atlantic to crash against the eastern coasts of Greenland. 

 All this was heroically shown by Fridtjof Nansen, during the epic drift of the '• Fram " from 1893 

 to 1896. 



The basin of the Arctic Ocean is surrounded by a broad continental shelf continuing upwards 

 to the immense plains of Siberia and Canada and made up of the old Precambrian basement 

 rocks of Angara and Laurentia, which have been levelled down during many glacial periods. 

 Local subsidences have broken up these ancient platforms into archipelagos, such as those to 

 the north of America; or formed shallow seas overlying the continents, like Hudson's Bay and 

 the Barents Sea. The chaos of icebergs heaving with the tides grind incessantly against the 

 cliffs of volcanic rock, an abrading action that has banished life from the near-shore seas. The 

 seaweeds cannot develop nor can shell-fishes find attachments. But on the slope a grey or 

 reddish, sticky mud contains a most abundant fauna. Here swarm the delicate transparent 

 shells of scallops, pink and pliant comatulid sea-lilies and great comose brittle-stars (" Medusa 

 heads ") with branching arms. Amid pale, rose-coloured shrimps swim numerous fishes. 



The marine millers-thumbs or cottids are predominant, whereas in our seas there are only 

 one or two species (Cotius bubalis and Coitus scorpius), which live in the beds of Zoslera grass 

 or in pools among brown seaweeds. Their large heads, which bristle with spines, and their 

 bulging throats give them a fearsome appearance, yet they are quite harmless animals. So are 

 the millers-thumbs of the polar regions. The males, which are smaller and less numerous than 

 the females, have higher and longer fins and are far more brilliantly coloured. Horns and 

 spines look more menacing and the facial tags of skin have greater extensions. When a female 

 is distended with ri[)e eggs, a male aj)proaches, watches over her and strives to get her to spawn. 

 No nest is built and the eggs are laid in no particular place. They may be found between stones 

 or in large empty shells forming an irregular heap, and in the middle may still be seen the track 

 of the egg-layer, .\fter this, the male keeps a more or less diligent watch around his future 

 offspring. 



The commonest cottid of the arctic seas is Icelus liamaltts, with a marbled-grey body and 

 a lateral line set with ossicles and having four spines on the heaii. The gill-cover spines are 



28 A ten-spined stickleback ( Pygosteus pungilius). 



A swimming burbot (Lota lota) : centre and below. 

 Photographs by H. II. Noailles. 



