Notices of Books and Papers. 59 



" Notes on the Occurrence of Mammoth Remains in the 

 Yukon District of Canada and in Alaska." By 

 George M. Dawson, C.M.G., LL.D., F.K.S., F.G.S. 



The following " Notice of Memoirs read before the Geological 

 Society of London, England," occurs in the December number of 

 the Geological Magazine, for 1893, pp. 574-575. 



In this paper various recorded occurrences of Mammoth 

 remains are noted and discussed. The remains are abundant 

 in, if not strictly confined to, the limit of a great unglaciated area 

 in the north-western part of the North American Continent ; 

 whilst within the area which was covered by the great ice mass 

 which the author has described as the Cordilleran glacier, remains 

 of the Mammoth are either entirely wanting or are very scarce- 

 As the time of the existence of the Mammoth the North American 

 and Asiatic land was continuous, for an elevation of the land 

 sufficient to enable the Mammoth to reach those islands of the 

 Behring Sea where these bones have been found would result in 

 the obliteration of Behring Straits. 



The bones occur along the northern coast of Alaska, in a layer 

 of clay resting on the somewhat impure " ground-ice formation " 

 which gives indications of stratification ; and above the clay is a 

 peaty layer. The author considers this " ground-ice " was formed 

 as a deposit when more continental conditions prevailed, by snow- 

 fall on a region without the slopes necessary to produce moving 

 glaciers. The Mammoth may be supposed to have passed between 

 Asia and America at this time. At a later date, when Behring 

 Straits were opened and the perennial accumulation of snow ceased 

 on the lowlands, the clay was probably carried down from the 

 highlands and deposited during the overflow of rivers. Over this 

 land the Mammoth roamed, and wherever local areas of decay of 

 ice arose, bogs would be produced which served as veritable sink- 

 traps. The author considers it probable that the accumulation of 

 "ground-ice" was coincident with the second (and latest) epoch 

 of maximum glaciation, which was followed by an important 

 subsidence in British Columbia." 



Note on the recent discovery of large Unio-like shells 

 in the Coal Measures at the South Jogqins, N. S. 

 By J. F. Whiteaves. Trans. Eoyal Society of Can- 

 ada. Separate Copies. 

 PI. I., Figs. 1, 2, pp. 21-24, issued December, 1893. 

 Beside the Presidential Address for the year, Mr. Whiteaves 

 contributed a second paper to Section Four of the Royal Society and 



