36 GEOLOGY OF THE THIRD DISTRICT. 



The. cut represents these fossils in their natural size : No. 1, is a small spiral undescribed 

 univalve, drawn from an imperfect specimen, exhibiting merely the general character. The 

 whirls or coils are more numerous and slender than those of the wood-cut, and the central 

 ones raised, not being on the same plane. The proposed name is Ophileta levata. It was 

 observed at all the localities of these layers on the Mohawk. 



No. 2, is more remarkable, consisting of many convolutions, resembling a single coil of 

 cord formed upon a flat surface, the diameter of the coil being usually about one inch. 

 From analogy of conformation, it evidently appertains to the same genus with No. 1, and its 

 proposed name is Ophileta complanata. It is more rare than the former, but is occasionally 

 met with in the same localities on the Mohawk, and it is also found in Lewis and Jefferson 

 counties. The shells of both species are exceedingly thin. 



No. 3, appears to have been one of the plates of the head of an encrinite, having a like 

 character. There are two general forms : one in which the slender divisions arc irregular, 

 as in the wood-cut, and showing but five in number ; in the other three are .six, and even 

 eight, four formed by the greek cross, and the others by ridges transverse to the cross. Its 

 locality is the quarry opposite to Fort-Plain. 



No. 4. Orthoceras primigenia, the oldest and smallest of the genus yet observed. The 

 specimens are all. much corroded by the action of the weather, which, however, exhibits their 

 structure to great advantage, showing the outer chamber which was the residence of the 

 animal, and the inner ones, which were numerous and near to each other ; also the terminal 

 part, which, being more solid, is usually uninjured. These orthocera are found in conside- 

 rable numbers in the quarry opposite to Fort-Plain, close by the side of the railroad. 



At Flint hill, near the line of the district, other fossils were seen which no doubt will be 

 noticed by the reporter of that district. They were an Orthis, in some measure resembling 

 the Testudinaria ; and the tail of a trilobite resembling the Illencus. 



Encrinal rings are obscurely seen associated with No. 3, and also at Canajoharie. 



The fucoidal layers are readily observed along the road from Flint hill to Amsterdam vil- 

 lage, appearing at the creek just below the railroad, and extending up the creek ; at Tripes 

 hill, being worked at the railroad, and in the Uttle valley near the village, where an orthostema 



