E. Hitchcock, Jr., on a New Fossil Shell. 239 



AkT. XIX. — A new Fossil Shell in the Connecticut River Sand- 

 stone ; by E. Hitchcock, Jr. 



I have lately found in the coarse sandstone of Mount Tom, 

 (Easthampton, Mass.,) a shell of a mollusk, the first I believe 

 that has been discovered in the sandstone of the Connecticut 

 Yalley. It is preserved and not petrified, and a considerable 

 part of it has disappeared. Enough remains however to enable 

 us to refer it to a family if not to a genus of shells. It is repre- 

 sented in the annexed diagram of the natural size as it lies in 



the rock. The upper part is gone, leaving an oval opening about 

 an inch and three quarters in one diameter and an inch and one 

 quarter in the other. It extends downwards, tapering somewhat 

 rapidly nearly an inch and a half, and is left without a bottom, 

 the lower opening being about an inch wide. The walls are 

 very thick, in some places nearly half an inch, and made up of 

 several concentric layers. 



From the resemblance of this shell to a model of the lower 

 valve of the Sphserulites calceoloides in the Cabinet of Amherst 

 College, it seems probable that it may be referred to that family 

 of Brachiopods denominated Rudista3 by Lamarck. 



Its lower parts as well as the lower valve are missing, but what 

 remains approaches nearer to the genus Sphaerulites than to any 

 other of the Rudistse of which I have seen specimens or figures. 



The geological position of this fossil will be readily under- 

 stood by referring to the description of Clathropteris rectiusculus 



