338 The American Geologist. November, 1894 
streams new existing. To that time of very high but geologically brief 
Pleistocene uplift we may refer the passage of the mammoth from the 
continent to Santa Rosa island, if it should be found that the preceding 
Pliocene submergence affected the entire coast line. w. r. 
Notes on the Pleistocene <;/' the Northwest Territories of Canada, northwest 
and west of Hudson Bay. By J. Burr Tyrrell. Geological Magazine, 
IV. vol. i. pp. 394-399, with map; Sept., 1894. In the years 1892 and 
1893 Mr. Tyrrell, for the Geological Survey of Canada, explored a large 
region from the Churchill river and lake Athabasca northeastward to 
Chesterfield iulet and Hudson bay. A preliminary account of his ex- 
ploration in 1893. from which he returned along the west coast of Hud- 
son bay, was given in the American Geologist last February (page 132). 
In the present short paper Mr. Tyrrell notes the occurrence of horizon- 
tal red sandstones and conglomerates, cut by trap dikes, similar 
lithologically with the Keweenawan series of the lake Superior region 
and probably of the same age, south of Athabasca and Black lakes and 
from Doobaunt lake (lat. 02° 30' to 63° 30', and long. 101° to 102° 30', 
with an altitude about 500 feet above the sea) northeast and east to the 
head of Chesterfield inlet. Laurentian gneiss borders the north 
side of lake Athabasca, reaches thence northeast to Doobaunt lake, and 
again appears along the north side of Chesterfield inlet. For 150. miles 
south of this inlet the greater part of the northwest shore of Hudson 
bay was found to consist of "green Huronian schists cut by many quartz 
veins, and sprinkled through with particles of copper pyrites." 
The whole region has been strongly glaciated, and the directions of 
the currents of the ice-sheet were noted in hundreds of places. On the 
upper Churchill river the glacial movement was prevailingly south or a 
little west of south; about lake Athabasca, Black and Daly lakes, and 
along the Telzoa river to Doobaunt lake, west; about the north part of 
Doobaunt lake and along the next 150 miles of the Telzoa river in its 
course through "Wharton, Aberdeen, and Schultz lakes, northwest; but 
on Baker lake, next southeast of Schultz lake, and along Chesterfield in- 
let, south to southeast; along the northwest coast of Hudson bay, also 
southeast: and in the vicinity of Fort Churchill, at the mouth of the 
Churchill river, three sets of strue were observed, respectively (1) S. 5° 
W. to S. 10° E., (2) X. 80° E., and (3) X. 55° E. 
The southward striation at Fort Churchill is preserved on the summits 
and northern sides of the hills, and Mr. Tyrrell supposes it to be the 
most recent of the three courses; but it may be questioned whether it is 
not more probably the oldest, being possibly as early as the time of max- 
imum thickness and extension of the ice-sheet. The northeastward 
striation would then be referable to the time of departure of the ice. 
when the land was depressed from its great preglacial elevation, so that 
the sea coming into the areas of Hudson strait and baymelted away the 
ice-sheet there faster than over the land areas on each side. This melt- 
ing appears to have opened a large embayment or basin into the central 
part of the originally ice-covered area, and to have finally turned the 
