204 Petry: VEGETATION OF NEW YORK STATE 
the bottom presents the appearance of a ravine running in that 
direction. The outlet of the basin lies to the southeast, where 
there is a notch about fifty-five feet in depth in the rim; this 
lowest point of the rim is forty feet above the bottom of the basin, 
which lies at an altitude of about six hundred ten feet above sea 
level. 
The basinlies in rather thick-bedded limestone for its entire 
depth, and the slopes are formed of debris of this material. 
iB 
A 
Fic. 1. Map of plunge basin, with isotherms of air temperatures (Fahr.) at 
1 in. from the ground, at noon, September 12, 1916. A, B, C and D indicate location 
of stations referred to in the text. Scale, 1 in. = 160 ft. 
Throughout this region the rock is extensively fissured and it is 
probable that the underlying bedrock here is traversed by crevices, 
since water does not collect in the basin. Except on a considerable 
portion of the north side, where there is a rock slide, the slopes are 
covered by a thin layer of nearly pure humus. Under the condi- 
tions which occur here this soil is always moist and plant growth 
in the basin is not restricted by lack of available water. 
The basin lies in a forest which has been somewhat disturbed 
by cutting. The interior of the basin itself is heavily wooded 
with Tilia, Ti huja, Betula lutea, etc. The outlet is a narrow notch 
whic sitar only half the depth of the basin. As a result of 
