REVIEWS 471 



These constitute a notable part — and, it will be agreed, a most valuable 

 part — of the paper. As by instinct, here and there the author drops into 

 details of location and measurement, and the text takes shape more as a 

 record of local facts than as a generalized intercontinental comparison, as 

 on pp. 266-73, where the . successive paragraphs are headed, "Basel,." 

 "Eglisau," "Leutkirch," "Drau Valley," "Lake Garda," "Cantu, Italy," 

 "Dora Baltea," "Rivoli," and " Bievre-Valloire " ; with similar local 

 treatment on pp. 283-95, ^-^^ elsewhere. Besides contributing such local 

 observations from the viewpoint of an American glacialist, the author 

 earns our thanks by giving a convenient map of the limits of "The Old 

 Drift," "The Middle Drift," and "The Young Drift" of the German 

 lowland, to the construction of which he himself appears to have made local 

 contributions. 



The comparison itself is introduced under the head of "The Oldest 

 Drift." America here makes its bow under an apology, as it were, for the 

 buried state of the oldest drift in the Keewatin field and the scanty, scattered, 

 weathered, remnant nature of the Jerseyan drift. But in reality these 

 ragged weathered remnants tell the very story of age that most becomes a 

 venerable drift. It is hard to pass complacently over so light a treatment 

 of the worn and aged Jerseyan formation. To put the still more scant 

 remnants of the old drift of the Allegheny Valley in their place as more 

 representative but emphasizes the personal viewpoint which runs through 

 the whole comparison and gives it at once its values and its limitations. 



In assembling the group of oldest glacial deposits of the two continents, 

 the old drift of the Allegheny basin (with some reservation), the Jerseyan 

 east of the AUeghenies, and the pre-Kansan of the Mississippi Valley, as 

 the American correlatives, are matched with the Scanian of north Germany, 

 the Giinz of the Alps, and the older Deckenschotter of the Alpine foreland. 

 The oldest Deckenschotter however has a better correlative in the oldest 

 member of the Columbian group, bordering the Jerseyan drift, both being 

 outwash aprons, and in the massive Natchez formation of the Mississippi 

 outwash train, and better still — because of similar topographic relations — 

 in the remnants of old outwash sheets that spread forth from the ancient 

 glaciers of the Uinta, Wasatch, and other montane centers of the Cordilleras, 

 which are unmentioned.* It would be ungracious to lay stress on this, did 

 not the American side of the comparison, and withal the rounder and truer 

 view, suffer from the neglect of some of America's most significant forma- 

 tions even when they have been fairly well worked. It may be noted also 

 that the Giinz drift has its best American correlatives in the Cordilleras. 



For the first interglacial series, the Aftonian of America is compared 



