182 



east, and it is largely from a study of the vegetation on these 

 slopes that the observations thus far recorded have been made. 

 But toward the west the ridges terminate in perpendicular cliffs, 

 at the foot of which are great masses of rocks waste (fig. 4) or 

 talus, derived from the disintegration of the overhanging pre- 

 cipices, and sometimes these are so extensive as to completely 

 bury cliffs several hundred feet in height. The upper part of 

 such a talus slope is steep, and, except at the very foot of the 

 cliff, is composed of large, loose blocks of rock, with practically 



Fig. 4. Talus slope along west face of West Rock ridge, Wocdbridge. A short 

 distance to the north of where this picture was taken the talus has become com- 

 pletely covered with forest. 



no soil between them. But as the bottom is approached the 

 gradiant becomes gentler, the rock fragments smaller, and a rich 

 soil collects. Here conditions are favorable for plants from the 

 very outset, since seepage water is abundant the year round and a 

 measure of protection from wind is afforded by the neighboring 

 hill. Succession proceeds with great rapidity, and the pioneer 

 associations quickly give way to forest. The mesophytism of 



