842 The American Naturalist. [September, 
Pre-Tertiary subsidence may have been at least to an equal depth. 
During this epoch of Tertiary subsidence, a thousand feet of Tertiary 
limestone were accumulated over the old nucleal island. 
3. After the close of Tertiary times, the Tertiary sediments were 
greatly warped and folded, concurrently with an emergence of the land 
from the sea. This movement was orogenic. 
4. Following this began the epoch of epeirogenic or regional eleva- 
tion. During Pleistocene time the island underwent the first of these 
upward impulses to its present height, with the exception of about six 
hundred feet represented in still later movement. This older Pleisto- 
cene or Yunque elevation raised the main area to a height of at least 
two thousand feet in its eastern half, and fifteen hundred feet in its 
western half. How much higher it extended we cannot tell, so great ` 
has been the erosion. Thiselevation was so rapid and general through- 
out the island that no coastal accumulations are preserved around its 
perimeter. This elevation likewise developed the present outline of 
the island almost in its entirety, and perhaps in greater area, which has 
since been destroyed by erosion. 
5. Following this older and greater Post-Tertiary elevation, and in- 
tervening between it and the time of the Cuchilla, or five hundred foot 
level, there was a long period of erosion, cutting down the country to 
the Cuchilla plain, which was at that time marine base level. 
6. Renewed and general elevation of the island commenced in recent 
times, after the period of rest recorded in the Cuchilla level. The later 
terraces, sea cliffs, base levels and modern coral reefs and savanna de- 
posits of the south coast were then elevated. It is also evident that in 
this later period, elevation was intermittent, accompanied by slight 
pauses. It is difficult to exactly fix the time of this latest elevation. 
It was certainly very recent, and a considerable period later than the 
old Yunque elevation. It cannot be older than the late Pliocene, and 
it may or may not be in progress at present. (Bull. Harvard Mus. 
Comp. Zool., Vol, XVI, 1895.) 
Former Altitude of Greenland.—Recent glacial studies in 
Greenland was chosen for the subject of the annual address of the Geo- 
logical Society of America, delivered by the President, T. C. Chamber- 
lin. In his closing remarks, the speaker referred to the former altitude 
of Greenland as follows: 
“ There is no ground to question the former elevation of Greenland. 
Its plateaus, like its valleys, indicate this; but glacialists are especially 
concerned to know whether the former elevation of Greenland was 
