Yol. 50.] IN CANADA AND ALASKA. 5 



limits of, a great unglaciated area there existing. With the exception 

 of the southern mountainous sea-margin of Alaska, and doubtless 

 also that of certain local inland ranges, this unglaciated area may 

 be described as comprising nearly the whole of Alaska, together 

 with a considerable portion of the adjacent Yukon District of 

 Canada. 



As the result of his explorations in this part of the continent, 

 the writer has been able to determine the fact that during the 

 glacial period the Rocky Mountain or Cordilleran region, from 

 about the 4Sth to the 03rd degree of latitude North, was at one 

 time buried beneath a great confluent ice-mass some 1200 miles in 

 greatest length in a north-west by south-east bearing, with an 

 average width of about 400 miles. 1 



This Greenland-like ice-cap was distinct from the still greater 

 Laurentide Glacier of Eastern North America, and, because of tho 

 trend of the mountain- ranges which it covered, it moved principally 

 in two directions — south-eastward and north-westward. The 

 south-easterly motion of one part of this ice-mass the writer had 

 demonstrated in 1877, 2 but it was not till 1887, and then as a 

 result of the Yukon expedition, that he was enabled to ascertain 

 the north-westerly movement of its northern part, and to show 

 that there was a definite limit to its extent in both directions. 

 Deing thus clearly distinct from any extension of polar ice, as well 

 as from the great Laurentide ice-mass, it became appropriate to 

 designate it as the Cordilleran Glacier. 3 Further evidence respecting 

 the northern limit of glaciation in this region has since been 

 obtained by Mr. R. G. M c Connell, of the Canadian Geological Survey 

 (1888), Mr. I.C. Russell, of the U. S. Geological Survey (1889), and 

 Mr. C. W. Hayes, of the same Survey (1891). 4 The area covered 

 by, and the directions of movement of, the Cordilleran ice-mass have 

 been approximately mapped in one of the papers above referred to, J 

 aud the later observations of the above-named gentlemen have not 

 in any material degree changed the indications there given. 



Within the area which was covered by the great Cordilleran 

 Glacier, remains of the Mammoth are either entirely wanting or 

 are very scarce. The reported finding of a tooth on the southern, 

 part of Vancouver Island, and that of a portion of a large bone 

 (which, though not determinable, may have belonged to such an 

 animal) in gravels worked for gold on Cherry Creek, 6 are the only 

 possible exceptions known to the writer, and the deposits from 

 which the last-mentioned bone was obtained may be of pre-Glacial 

 age. 



1 ' On the later Physiographical Geology of the Rocky Mountain Eegion in 

 Canada.' Trans. Royal Soc. Canada, vol. viii. (1890) sect. iv. p. 27. 



2 Report of Progress, Greol. Surv. Canada, 1877-78, pp. 136 B, 151 B ; Quart. 

 Journ. Greol Soc. vol. xxxiv. (1878) p. 119, vol. xxxvii. (1881) p. 283. 



3 'American Geologist,' vol. vi. (1890) p. 162. 



4 Annual Report, Geol. Surv. Canada, 1888-89, p. 28 D ; Bull. Geol. Soc. 

 Am. vol. i. (1890) p. 144 ; National Geogr. Mag., Washington, vol. iv. p. 157. 



Trans. Royal Soc. Canada, op. cit. pi. ii. map no. 4. 

 u Okanagan District, British Columbia. 



