216 J. D. Dana— Geological Relations of the 
bands of hornblendic mica schist: one of these bands has a 
border of the micaceous augite-noryte just mentioned. In the 
limestone just north of this mass, facing the river, occur the 
supposed dikes or veins mentioned on page 202. Some of them 
consist of pyroxenyte ; others of coarsish hornblendyte; ver 
fine-grained hornblendic rock looking like hornblende schist 
(Ae) ; very fine-grained hornblendic mica schist ; augite-noryte. 
As already admitted, there is here abundant evidence of 
a former plastic state in at least part of this augitic and horn- 
blendic material. Still, there are strong reasons for question- 
ing the idea of its deep-seated origin. (1.) The variety in the 
constitution of the mass bordering the limestone and in the sup- 
posed dikes or veins is very unlike what is ordinarily found in 
crystals, looks as if it may have been in part at least a result of 
mixture attending original deposition. 
Further (4.), there is the decisive fact that these intercalated 
fied beds to the northward and on the shore is what should be 
expected ; for the limestone is bordered to the eastward in the 
one case by true mica schist, and, in the other, by augitic or 
hornblendic beds ; and the associations at Montrose and Stony 
Points are similar. This view is also sustained by the occur- 
rence in the limestone near the schist, 1000 yards from the 
Point, of coarse spots of pyroxene with mica and chlorite, 
rudely in layers, which must be due to the original deposition 
of impurity and metamorphic action. The augitic rock (pyrox- 
enyte) on the east of the limestone at the Point outcrops (owing 
to excavations in the drift) for 200 yards from the shore; but 
its place beyond this continues covered for three-fourths of a 
mile, and here the rock is arenaceous mica schist; the spots of 
pyroxene are its only representative. 
