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ms J 
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80 THE SCOTTISH NATURALIST 
numbers suggest, for in one case (1920) a Walrus which 
appeared in July remained continuously till, at any rate, 
mid-October, and it is possible that the autumn and winter 
records of our list represent only the earliest recognition 
of individuals which till then had remained unobserved, 
having lurked since the summer months in secluded parts 
of our coast. 
To what, then, are the summer visits of the Walrus due? 
In the first place, they seem to be associated with the annual 
breaking-up of the winter’s ice formed along the Arctic 
coasts and in the narrower seas. Mr J. Mathieson tells me 
that drift-ice from Barents and Kara Seas fills up the area 
between Bear Island and Spitsbergen during the winter. 
In late spring or early summer the drift and land ice 
begin to give way under rising temperature. On _ his 
expedition to Spitsbergen in 1920 Mr Mathieson met the 
close pack in June, 60 miles south-west of the island, and 
had to follow the edge of the pack for 80 miles before 
attempting to force his vessel through. The breaking-up 
of the winter’s ice, and its gradual drift to sea under the 
influence of ocean currents and winds, probably supplies 
a first cause of the Walruses’ visits, for it suggests the 
possibility of the disruption of a colony about the breeding 
season and the involuntary southwards drift of one or more 
ofits members. That such drifting of Walruses did actually 
take place is shown by the experience of the whale-ship 
Arctic, the captain of which saw, on 28th August 1867, in 
lat. 69°N., long. 64° W., “two or three hundred basking 
upon the ice, and sent out his boats to the attack.” One 
of these Walruses was brought alive to Dundee.! 
The southern limit of drift-ice to the north of the North 
Sea lies roughly in the latitude of 62° N., or in a position off the 
eastern coast of the Faroe Islands, but this marks practically 
an unattainable maximum for an ice-borne Walrus. Wemust 
assume, therefore, that the journey, begun as an involuntary 
drift, is completed by more voluntary movements on the 
part of the migrant, and these would probably be determined 
1F, W. Southwell, Seals and Whales of the British Seas, 1881, 
Pp. 35. 
