100 



PALEONTOLOGY OF NEW-YORK. 



FOSSILS OF THE UPPER GRAY SANDSTONE OF THE CLINTON GROUP. 



The Clinton group proper is in many places terminated by a thick mass of heavy bedded 

 sandstone. This sandstone is for the most part destitute of fossils ; but in a few localities it is 

 fossiliferous, and these fossils are so peculiar that I have preferred to give them by themselves. 



In the more eastern localities of this group, and as far west as Oneida county, this mass of 

 sandstone forms a conspicuous feature in the group. There are several localities south of Mo- 

 hawk village, where this rock is in great force, forming a terrace above the more destructible 

 layers of the gi'oup, and below the soft marls of the Onondaga-salt group, the Niagai'a group 

 having little or no importance in that neighborhood. At Tisdale's mill, this mass of sandstone 

 is very conspicuous (See section page 16 of this volume) ; and in localities east of this point, 

 it is more or less conspicuous and important. 



This mass of sandstone in some of its localities was described by Prof. Eaton as the Grey 

 band, which, becoming confounded with the gray mass terminating the Medina sandstone, has 

 produced some confusion heretofore in the identification of strata associated with these tM'o 

 very distinct formations. 



It should be remarked that this mass is not known to be fossiliferous in its more eastern 

 localities ; the first place at which fossils were noticed being at Remington's quarry, south of 

 Mohawk, and again at another locality a mile or two west of this one. In the southwestern part 

 of Oneida county, I have been unable to find this mass in place, though fragments containing 

 fossils are frequently seen. 



496. 1. MYALINA MYTILIFORMIS {n. sp.). 



Pl. XXX. Fig. 1 a, b, c, d. 



Shell ovate, elongated ; beak acute, anterior margin sub-alate ; cardinal line straight ; sur- 

 face of cast marked by concentric undulations indicating stages of growth. 



The specimens seen are all in the condition of casts, as are the other fossils of this sand- 

 stone. In some of the casts the concentric lines are not perceptible, while in others they are 

 quite conspicuous. The cardinal margin is often arched from pressure, and from the same 

 cause the anterior margin often appears more alate ; at the same time pressure in the direction 

 of the two margins renders the anterior fold inconspicuous. 



This shell appears to be allied to Ambonychia, but is wanting in the posterior alation, and 

 in other characters of the hinge and beak possessed by that genus. The present species is the 

 earliest form of this type known to me, though it appears in all the succeeding groups as high 

 as the Chemung. 



I have referred this shell to the Genus Myalina of de Konikck, from its external form 

 alone, having had no opportunity of examining the entire shell or its internal cbaracters. In 



