M. Stirrup — True Horizon of the Mammoth. 81 



Mammotb-remains in Nortli-West America " the author cites the 

 presence of Mammoth bones in a layer of clay resting on the 

 "ground-ice" formation of the northern coast of Alaska and other 

 areas. 



I drew attention to this position of the Mammoth bones above the 

 solid ice both in North Siberia and Alaska, as proved by several 

 explorers, in my paper on " The True Horizon of the Mammoth " 

 (Geol. Mag., No. 345, p. 107, March, 1893), in which I claimed for 

 the Mammoth an existence long after the period assigned for its 

 extinction by Sir Henry H. Howorth. 



I see that Sir Henry, in the discussion of the paper, very naturally 

 disagreed with the conclusion of Dr. Dawson as to the age of what 

 is called by Amei'ican geologists the "ground-ice" formation, and 

 was of opinion " that this ice has accumulated since the beds were 

 laid down in which the Mammoth-remains occur, and that the ice 

 was not there when the Mammoth roamed about in the forests where 

 he and his companions lived." 



Furthermore, he is reported to have said that " humus and soil 

 cannot accumulate upon ice, except as a moraine," both of which state- 

 ments are controverted by the explorations of recent and competent 

 observers who have examined these regions. 



In support of my contention I need only refer Sir Henry to the 

 explorations of Dr. W. H. Dall in the Alaskan regions (which I 

 quoted in my previous paper), and to the evidence of other observers 

 which Dr. Dall summarizes in the Bulletin of the United States 

 Geological Survey, No. 84, pp. 260-267, recently issued. Dr. Dall, 

 speaking of the " ground-ice " formation, says " a remarkable 

 formation has been recognized in many places in the northern part 

 of Alaska, in which solid beds of ice of considerable thickness 

 perform the functions of rock strata and are covered by beds of blue 

 clay containing numerous remains of Pleistocene mammals, or by 

 beds of alluvium which sustain a layer of turf, with ordinary 

 profuse herbage of the region, or even small thickets of birch, alder 

 and other small Arctic trees." 



These mammalian remains include, among others, tusks, teeth and 

 bones of the Mammoth, E. primigenius, bones of Bison antiqmis, and 

 the Musk Ox. The mode of origin of this ground-ice formation is 

 undoubtedly difficult of explanation, but its position beneath the 

 Mammoth-bearing beds is uniformly the same, whether in the cliffs 

 of the coast or in those bordering the Alaskan rivers. 



Dr. Dall, referring to the strati graphical position and mode of 

 accumulation of the bones, says, " that all the circumstances point 

 toward the view that the ice preceded and subsequently co-existed 

 with animals whose remains are now found in its vicinity." 



Lieut. J. 0. Cantwell, United States Revenue Marine, reporting 

 on the Kowak river ice-cliffs discovered by him in 1884, says " they 

 are composed of solid ice, covered by a layer of dark-coloured earth, 

 uniformly about 6 feet thick, the whole rising to the height of 15 to 

 150 feet, with trees 4 to 8 inches in diameter growing on the 

 surface." 



DECADE IV. — VOL I. NO. II. 6 



