CHAMPLAIN DIVISION. 
395 
The graptolites have been mentioned as extremely abundant. Testacea and Crustacea are 
rare in most places observed in the First geological district, but at some localities they are 
common. The following localities show these fossils : 
1. Near the sawmill on the Saratoga shore of the Hudson, below the ferry from Sandyhill, 
and above Baker’s falls. 
2. Cohoes falls and the vicinity, where two species of trilobites and several of small bivalve 
shells occur. 
3. The bed and banks of the Champlain canal, between Waterford and the Mohawk river. 
Some fossils have been found in other places in this slate, as at the north end of Troy, in 
River-street and Mount Olympus, where orthoceratites were found ;* the banks of Saratoga 
lake, near Snake hill; the rocky blulf bank of the Hudson, at the city of Hudson ;* and the 
banks of Kinderhook creek, between Columbiaville and Kinderhook at the lower falls. 
Among the fossils found at these various localities, are, 
Trilobites. at least 3 species. 
Orthoceratites. “ 2 
Trocholite... “ 1 “ 
Bivalves. “ 3 “ 
Crinoideal vertebral spines. 2 “ 
“ Flinty slate.” j Siliceous slate is quite common as a modified form of the rocks of the 
Hudson-river group, and it ought perhaps to be described among the metamorphic and altered 
rocks. It occurs in very numerous local patches and narrow ridges in the Hudson valley, 
and mostly near the Hudson river, between Sandyhill and Marlborough, and it is also found 
in Orange county. It may be seen at the following localities : 
1. About two and one-half miles south-southwest of Hudson, in the bed of a small stream. 
This is to the west of the Highland turnpike, and after crossing the brecciated lime¬ 
stone, the slate is again observed, which is highly siliceous, passing through all the 
shades of difference from common siliceous slate to basanite and hornstone. 
2. About one and a half miles southwest of Clermont. The slate passes through all gra¬ 
dations from fine argillaceous slate to basanite. Some of it would answer for hones ; 
and I have used a piece of the rock, of a suitable degree of hardness, for setting a 
fine edge on a razor and a penknife. 
3. Several localities in Germantown. Flinty and siliceous slate were seen in ridges not far 
to the west of the Lutheran church in Germantown; and also on the road from that 
church to a point on the post-road, one mile south of Clermont, Columbia county. 
♦ Vide Eaton’s Geological Text-Book, 2d edition, Note, p. 72; and Geological and Agricultural Survey of the vicinity of the 
Erie Canal, p. 67. 
t Eaton’s Geological and Agricultural Report of Erie Canal, p. 69. 
50* 
