1086 The American Naturalist. [December, 
resultant of valley erosion, glacial scoop, and drift barriers, with per- 
haps a slight element of orography. The deepening of the lakes to the 
southward is the result of the narrowing of the ice between contracting 
valley walls which increases the vertical pressure and hence intensifies 
the erosion. (Bull. Am. Geog. Soc., 1893.) 
In a review of the knowledge of the paleolithic man in North Amer- 
ica M. Boule remarks that the recent work of Mr. Holmes does not 
invalidate the discoveries of paleolithic objects in America, and 
particularly those of Dr. Abbott, which M. Boule considers to be “true 
finds” in every sense of the word. 
It is suggested by Mr. F. W. Hutton that the Ostriches of Africa and 
South America have orginated in the Northern Hemisphere possibly as 
swimming birds—and the Gastornithide, which have relations with the 
Anatide, may be their ancestors. (Proceeds. Austral. Assoc. Adv. 
Sci., 1892.) 
According to Dr. Du Riche Preller, the Engadine Lakes owe 
their origin to the subsidence or dislocation of the old divide of the Inn 
and Bargalia systems, and the consequent deflections to the south of the 
original Inn sources. From a powerful Alpine torrent the Inn was 
reduced to a small stream without sufficient volume or fall to carry 
away the deposits brought down by lateral torrents. These deposits 
accumulated and thus the lakes were formed by the weakened river 
being banked up at various points. (Geol. Mag., Oct., 1893.) 
From the evidence of marine fossil shells in the Bowlder Clay on the 
Bay of Fundy just west of Saint John harbor, Dr. Robert Chalmers 
concludes that the height of the land on this part of the Bay during 
the Glacial period must have been 100 to 200 feet lower than at the 
present day, relatively to the sea. Also since the striæ on the rocks 
underneath the bowlder-clay indicate several ice movements varying in 
direction from S. 2° W. to S. 65? E. the formation of the lower 
bowlder-elay cannot all be due to one body of ice. (Bull. Geol. Soc. 
. Am., 1893.) 
