Limestone Belts of Westchester County, N. Y. 369 
On its eastern side, toward the base of Stony Point, it is 
followed conformably by mica schist and micaceous gneiss, 
coast by a massive granitoid rock which is intermediate litho- 
logically between soda-granite and ordinary granite, the feld- 
spar being half orthoclase. Then succeed the noryte and chrys- 
olitic rocks of the areas marked z’ and z on the map on page 
5, then the soda-granite of y, and lastly, near the extremity 
of the Point, the mica sehist or micaceous gueiss of 2 The 
succession along the north side of the Point from west to east 
thus is: (1) schist, (2) semi-soda-granite, (3) chrysolitic rocks, (4) 
soda-granite, (5) schist. Going between these points by the 
south a wholly different state of things is found; schist continues 
all the way; and the strike varies from N. 20° E. where at ad- 
joins the limestone, through northwest and west-and-east, to N. 62° 
-70° H,, which is the strike on the south side of the Point, 
south of the eastern soda-granite, as already stated (page 218). 
of the schist into the soda-granite with the rock very garnet- 
iferous at the junction—a good example of which may be seen 
northeast of the house on the south side of the point. 
Notwithstanding doubts on some points, there is no ques- 
tion that the schist has the flexure pointed out, and is one con- 
tinuous stratum; and that the limestone is an adjoining stra- 
tum, and must have participated in the flexure. Further, since 
the dip of the schist on both the south and west sides is towar 
the axis of the flexure, the limestone stratum is probably an under- 
lying one, which would make the schist and soda-granite supe- 
rior to it in stratigraphical position. Now since the Cruger’s 
limestone adjoins a schist that is similar to that of Stony Point in 
kind, and position, and in all of us relations to the soda-granite, the 
Cruger’s limestone must be of the same stratum with the Tompkins’ 
Cove limestone; and, if so, it ts one, also, with the limestone of 
Canopus Hollow. : 
The area Number 80 is like 29 in extending along a promi- 
nent valley—Peekskill Hollow—northeastward far into the Ar- 
chean. The most northern locality of limestone which I have 
found is a mile and a half above Tompkins’ Corners (west of 
Am. Jour. een ee Series, Vou. XX, No. 119.—Nov., 1880. 
