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EXTRACTS FROM THE JOURNALS. 
AGRICULTURAL GEOLOGY. 
Portage, Ithaca, and Chemung Groups in the Schoharie county Districts. 
The development of the Hamilton shales is excessive in the 
eastern part of New York, but there are only slight differences in 
the lithological characters. At Summit, in Schoharie county, in 
a deep gorge near the village, the Chemung group occupies the 
upper part and the higher slopes adjacent to it, and also the hills 
above the village. As yet, however, the fossils of the Chemung 
narrows are not common or numerous; and it seems to be estab- 
lished that the fossils of the Hamilton shales go up higher into 
the shales and flags, and occur nearer to the base of the Catskill 
division, or old red sandstone, than at the west. The flags at the 
top of the Helderburgh range, and the rocks occupying the highest 
position in the southern towns in Albany and Schoharie counties, 
belong to the Chemung group. 
The purposes of agriculture do not require an identification of 
the rocks under consideration: they belong chemically and miner- 
alogically to the same class. The structure, the tendency to de- 
composition, and the soil which is formed by disintegration, does 
not differ essentially in Albany county from that of Allegany or 
Cattaraugus county. We do not find the exact equivalents when 
they are tested by fossils; it is possible, however, that this may 
be ow4ng to exposure. Other fossiliferous strata than those, for 
example, which are exposed in Chemung, may be exposed in Al- 
bany or Schoharie counties, or in the rocks of the eastern part 
of the state. Where fossils are limited to narrow bands, and 
where their vertical range is small, corresponding strata at two 
distant points may be concealed at one or the other. The kind of 
distribution alluded to, is that which prevails. A stratum from 
two to twelve inches is loaded with fossils; but above or below, 
for fifty or one hundred feet, they are either very scarce or do not 
exist at all. This is the general mode in which they are distri- 
buted in thick beds, sandstones and flags, a mode which does not 
seem to prevail in calcareous shales and limestones. In these de- 
posites, it is not uncommon to find organic bodies distributed 
throughout the whole mass. 
Localities where the sandstones and flags described above may 
he examined. Many localities have already been mentioned, at 
