170 
GEOLOGY OF THE FOURTH DISTRICT. 
stream rises again in the Caledonia spring, seven miles distant; but the only facts advanced 
are the disappearance of the one, and the occurrence of the other with no apparent origin. 
The Caledonia spring, from the great quantity of water it affords, is evidently the common 
outlet for a large area in its vicinity; but whether it is supplied from so great a distance as 
Le Roy, may be questionable. To the west and southwest of Caledonia the surface in wet 
seasons presents numerous small lakes or ponds, which drain off into the fissures below; and 
it is evident, from the nature of the rock, that there is a large reservoir constantly maintained. 
The springs at Canoga, in Seneca county, owe their origin to the same cause, as also those 
at Springport, on the opposite side of the lake. 
Agricultural characters. 
The character of the soil covering this rock varies, to a considerable degree, according to 
its development. Where the rock is thin, as in the eastern part of the district, it scarcely 
produces any effect upon the surface ; but where thicker, it has essentially modified the charac¬ 
ter of the soil. In Seneca county the soil covering the northern part of this rock is clayey, 
but becomes more loamy toward the southern part; in the western and central part of the 
county it is frequently covered with a loamy soil, but the characters appear entirely due to 
the accumulation of northern drift. 
Where the rock becomes thicker and the quantity of hornstone greater, it has produced a 
coarse siliceous or silico-calcareous soil, from the destruction of the rock in the manner before 
described. The surface in such cases is often forbidding, from the great quantity of frag¬ 
ments of the “ chawed rock,” as it is termed ; but where the larger of these are removed, the 
soil proves of the best quality. The constant destruction of the larger fragments by the 
action of frost and water liberates fresh calcareous matter, which must constantly act as a 
fertilizer. 
Organic Remains of the Corniferous Limestone . 
The central and lower portions of this rock usually exhibit few forms which are peculiar to 
it, though they serve, from their association, to aid in the identification. In the higher por¬ 
tions, which are nearly or entirely free from hornstone, the fossils are peculiar, and serve at 
once to identify the rock, being known in no other. Among these fossils are two trilobites, the 
Odontocephalus selenurus of Green, and a Calymene. So abundant is the former of these 
at Schoharie and other places, that it alone is the fossil entirely relied on, and the rock is 
known as the “ Selenurus Rock.” The other trilobite is scarcely less characteristic. In 
many places in the Third District, and in Seneca county in the Fourth District, the Stropho- 
mena lineata of Conrad is the typical fossil, but it rarely occurs at any point west of the last 
named locality. 
There are several species of the genus Cyrtoceras which are apparently confined to this 
rock, and in the eastern part of the State are common, while in the Fourth District they are 
but occasionally seen, other forms taking their place. 
