390 W. M. Davis—Nonconformity at Rondout. 
by a stratum of almost quartzitic texture, white or bluish in 
color, and fifteen to twenty feet thick. The most northeastern 
point where it was certainly recognized was in New Salem at 
the beginning of the horse-railroad leading to the cement quar- 
ries in Whiteport; thence southwestward it may be frequently 
seen at the foot of the limestone bluff, a hard, compact bluish 
quartzose rock. At the foot of the map, where the limestone 
ridge breaks down, it is white, and so appears again about two 
miles west in the fine anticlinal near Whiteport where the 
Water-lime has been deeply quarried. It holds no pebbles or 
fossils here and is not yet thick enough to have a noticeable 
effect on the topography. ; 
The first of the limestones is seen in the quarry on the hill 
overlooking Rondout (Section II), where. it rests directly on 
the Hudson River rocks, as will be further mentioned below. 
As measured by Mr. J. G. Lindsley, superintendent of the 
Newark Lime and Cement Co., it is six to eight feet thick, and 
from its abundance of corals it is considered the equivalent of 
the Coraliine limestone of Schoharie, the thin eastern exten- 
sion of the Niagara of Western New York. 
The Water-lime and Tentaculite, to which Lindsley adds the 
Stromatopora and Ribbon limestones, have a total thickness of 
seventy feet. The layers are generally smooth and even, espe 
‘cially in the upper part and are readily recognized, but fossils 
are not common. ‘The lower beds are deeply quarried at 
and fifty. These I have mapped as the Lower and we 
* See J. Hall, Pal. N, Y., iii, 26, and Amer. Assoc. Proc., xxii, 1873, 321- 
