Personal and Scientific News. 141 
PERSONAL AND SCIENTIFIC NEWS. 
Pleistocene Papers at the Meeting of the Geological 
Society op America, Washington, Dec. 20-31, 1890. — Prof. J. 
W. Spencer's paper, read Monday afternoon, Dec. 20. on " Post- 
pliocene Continental Subsidence," set forth the evidences afforded 
by fiords and submarine valleys, like that of the Hudson, that the 
greater part of North America has been depressed 3,000 feet, 
more or less, since the Pliocene period. On the Atlantic coast 
northward to New York and Massachusetts, and on portions of 
the shores of the eastern provinces of Canada, this subsidence is 
still going forward, as shown by stumps of trees standing where 
they grew but now covered by the sea. But the region about 
Hudson bay, according to Dr. Robert Bell's observations, is now 
being elevated, and professor Spencer believes that the postglacial 
elevation of the region of the Laurentian lakes, which in places 
has amounted to not less than 500 feet, is also still slowly in 
progress. 
Monday evening Prof. W. M. Davis presented << Illustrations of 
the Structure of Glacial Sand Plains," a series of excellent stere- 
opticon views, from photographs by himself and 11. L. Rich, of 
small sand plains of stratified drift, with their assoeiated esker 
ridges of gravel and sand, situated in the vicinity of Boston. 
The formation of these deposits was referred to the action of 
streams produced by the melting of the ice-sheet, the materials, 
which were rapidly deposited, having been englacial drift enclosed 
in the lower part of the ice. 
In the same evening session, Mr. I. C. Puissell gave a very in- 
teresting account of his explorations during the past summer, with 
Mr. Mark B. Kerr, on Mt. St. Elias and the mountains extending 
thence fifty miles southward to Yakutat bay. A large map of I he 
mountain ranges and glaciers was exhibited, showing valley 
glaciers on the south, terminating in Disenchantment bay ; but 
Erom this bay and Yakutat bay northwestward the valley glaciers 
merge into a terrace-like ice-field, uamed by Russellthe Piedmont or 
Malaspina glacier, ten to twenty miles wide and more than fifty 
miles long, bordering the coast. The surface of this greal ice 
field in its seaward portion is covered with drift to depths varying 
from a lew inches to several feet ; and on this Buperglacial soil 
:i profuse growth of flowering plants springs up in many places 
during the short summer, while other parts of the same trad are 
Clothed with a coniferous forest. Itivers How through the Malafl 
