ORGAMC REMAINS LAID BARE THEREBY. 371 



land animals (probably ammonites or spirulas), and 

 plants ; all in the same place. They are found on the 

 deepest valleys and the highest hills. The valleys most- 

 ly bedded with limestone ; and in the midst of large 

 masses of this, the petrifactions are found. As you ascend 

 to a certain height, the hills on each side of the valley, 

 the limestone disappears, and the soil is totally different. 

 Confused masses of the slate kind are found, some lying 

 horizontal, others projecting from the ground at an angle 

 of about forty-five degrees. In the midst of these masses 

 of slate-rocks are found the same petrifactions." 



The whole ridge called the Helleberg, about twelve 

 miles west of Albany city, is a sort of argillaceous lime- 

 stone, made up as it were of pectens, terebratulas, spi- 

 nilas, and oceanic relicks. It was here that the very 

 large and highly remarkable spirula was discovered, 

 which Simeon De Witt has circumstantially described. 

 His narrative, with a figure, may be seen in the Medical 

 Repository, vol. 10, p. 350. 



Within the limits of Coeyman's patent, about twenty 

 miles south of Albany, there is a great body of Luraa- 

 ehella marble, disposed in regular strata. Attempts have 

 been made to work it ; but the quantity of siliceous mat- 

 ter with which it abounds, renders it hard and difficult to 

 polish. Its constitution is very curious. The slabs 

 I received from Roger Strong, Esq. and which are now 

 in the mineralogical cabinet of the New- York Institution, 

 contain a variety of animal remains, and all of them 

 oceanic. Among these are 



Belemnites. 



Anomlas. 



Encrinites. 



