6 DR. G. M. DAWSON ON MAMMOTH-REMAINS [Feb. 1 894, 



The likeness of the non-glaciated north-western portion of 

 North America, with its abundant Mammoth-remains, to the 

 similarly characterized northern part of Asia has already been 

 recognized. The purport of the foregoing remarks is to indicate 

 the existence of a south-eastern boundary to the Mammoth-inhabited 

 portion of Alaska and the Yukon District; nor can it be reasonably 

 doubted that the North American and Asiatic land was continuous 

 at the time of the existence of the Mammoth, or for some portion 

 of that time ; for an elevation of the land sufficient to enable the 

 Mammoth to reach the islands in Bering Sea, already referred to, 

 would result in the obliteration of Bering Straits. 



Many conjectures have been advanced as to the mode of occurrence 

 and origination of the ' ground-ice formation,' in association with 

 which the bones of the Mammoth and other animals are found along 

 the northern coasts of Alaska. Dall summarizes these in his work 

 previously cited, 1 and it may now be confidently assumed that the 

 descriptions of Kotzebue and his party, of Capt. Kellett and others 

 on the ' Herald,' of Dall and Lieut. Cantwell, 2 correctly indicate the 

 facts of the case. The clearest descriptions of the phenomena are 

 those of Seemann and Dall. 3 From these it appears that the lower 

 parts of cliffs which have some extent on Kotzebue Sound are 

 composed of solid ice, somewhat discoloured and impure, and showing 

 indications of stratification. Above this ice rests a layer of clay, 

 in which the bones occur, and capping the whole is a peaty layer 

 supporting the vegetation of the region. It is further apparent that 

 this or a very similar formation occurs at a number of points along 

 the northern coast of Alaska, but nothing has been adduced to show 

 that it is absolutely continuous over any great area ; — there is, in 

 fact, some reason to believe that it is confined to limited tracts, even 

 in the vicinity of Kotzebue Sound. 4 



In the present connexion, the ' ground-ice formation ' is of interest 

 only in so far as its existence and the mode of its origination 

 may throw light on the date and method of entombment of the 

 Mammoth-remains associated with it. "With respect to the origin of 

 the deposits, the writer ventures to offer the following suggestions. 



The country in which the ' ground-ice formation ' occurs is low 

 in its relief, and the formation occupies its lower tracts. The ice 

 itself must undoubtedly have been produced upon a land-surface, 

 and since the time of its production this surface can never have 

 been covered by the sea ; for this would inevitably have reduced the 

 frozen condition of the overlying clays, and have resulted in the 

 destruction of the icy sub-stratum as well. 



With an elevation of the land by an amount of 300 feet or more 

 (such as appears to be required by the Mammoth-remains on islands 

 already mentioned) the warmer waters connecting with the Pacific 



1 Bull. U.S. G-eol. Survey, No. 84, pp. 260-264. 



2 ' American Geologist,' vol. vi. (1890) p. 51. 



3 ' Voyage of H.M.S. ' Herald,' ' vol. ii. pp. 33 et seqq. ; Bull. U.S. Geol. Surv. 

 No. 84, pp. 261 et seqq. 



4 'American Geologist,' vol. vi. (1890) p. 52. 



