THE 
i 
E 
AMERICAN NATURALIST. 
E VoL. xx—NOVEMBER, 1886.—No. 11. 
_ COMPARATIVE STUDIES UPON THE GLACIATION 
_ OF NORTH AMERICA, GREAT BRITAIN 
| AND IRELAND) 
\ 
= BY PROFESSOR H. CARVILL LEWIS. 
4 ()BSERVATIONS extending over several years upon glacial 
E phenomena on both sides of the Atlantic had convinced the 
=- author of the essential identity of these phenomena; and the 
object of this paper was to show that the glacial deposits of Great 
Britain and Ireland, like those of America, may be interpreted 
__ Most satisfactorily by considering them with reference to a series 
z of great terminal moraines, which both define confluent lobes of 
ice, and often mark the line separating the glaciated from the non- 
glaciated areas. : ; 
„€ paper began with a sketch of recent investigations upon 
_ the glaciation of North America, with special reference to the — 
Significance of the terminal moraines discovered within the last — 
2 few years. The principal characters of these moraines were _ 
Siven, and a map was exhibited showing the extent of the gla- 
_ Slated areas of North America, the course of the interlobateand 
5 terminal moraines, and the direction of striation and glacial -a 
Movement, It was shown that apart from the great ice-sheet of 
Northeast America, an immense lobe of ice descended from 
Alaska to 
Vancouver's island on the western side of the Rocky a 
_ ns, and that from various separate centers in the Cascade, © 
Sierra Nevada and Rocky mountains there radiated smaller local = 
The mountains encircling the depression of Hudson bay 
“Abstract of a paper read at the Birmingham meeting of the British Association, = a 
1886. aa 
*X.—no. xr, . 61 
