Ko. 27b.] 
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separated by thin seams of the latter; and again, a thick mass of shale 
containing little silex and no sandstone. A similar quarry has been 
opened by Mr. Tuilegar, four or five miles east of Elmira; and here the 
layers are very uniform, from half an inch to two inches thick, and di- 
viding by the vertical joints into slabs from six inches to two or three 
feet wide, and from four to six feet long. The sandstone contains a 
few species of Orthis, but the greater proportion of fossils are found in 
the shale. Wisner's quarry is near the junction of this group, with the 
Ilhaca group below, or rather in the upper part of the latter, which ap- 
pears at this point, the rocks rising southward from Horseheads to the 
Chemung river. 
The rocks of this group, containing an abundance of fossils, occur 
on a small creek coming into the Chemung valley from the northwest, 
and also on the Sing Sing creek, passing through Bigflatts. On the 
south side of the Chemung river, in Southport, the banks of the valley 
exhibit the rocks of this group with their peculiar fossils. 
Between Elmira and Chemung they are seen at numerous points, but 
no where in the county so well as at the Chemung upper narrows, about 
eleven miles below Elmira. Here the excavation lor the road along the 
margin of the river has exposed more than 100 feet of rocks, contain- 
ing abundance of the characteristic fossils, and in their greatest beauty 
and perfection. At a certain point in the mass exposed, we find a pe- 
culiar coralline fossil, confined to a thin stratum, and extending along 
the whole distance of the exposed rocks; it has also been found at other 
localities. 
The mountain above the rocks exposed, at Chemung narrows, rises 
400 or 500 feet, and is probably capped, as some of the hills in the 
neighborhood, by the conglomerate, which is the limit of the Chemung 
group upward. Farther south, near Tioga point, rocks of the same 
group occur in the bank from 100 to 200 feet above the river, and some 
of the sandstone layers are 3 or 4 feet thick, and highly silicious. I 
was informed that on the top of the hill the conglomerate is quarried 
for use on some of the public works below Tioga point. 
At the Chemung upper narrows, and at several other localities, there 
occurs in this group a stratum of concretionary sandstone of a peculiar 
character. In a few instances only are the concretions perfectly form- 
ed, but generally have one side imperfect, with a solid nucleus partially 
surrounded with concentric laminae, which easily separate from each 
