PALEONTOLOGY: EASTERN MASSACHUSETTS. 



Ahadeds W. Grabac. 



FossiLiFEROcs rocks, belonging to the following geologic forma- 

 tions, are found in eastern Massachusetts. 



Recent. 

 Neocene, 



Pliocene. 



Miocene. 

 Eocene (Erratics). 

 Cretacic . 



Upper? Cretacean. 



Middle? Cretacean. 

 Jurassic ? 

 Triassic. 

 Carbonic 



Middle Carboniau. 

 Devonic. 



Upper Devonian. 

 Cambric. 



Upper Cambrian (Erratics) . 



Middle Cambrian. 



Lower Cambrian. 



It will be seen that, of the larger rock series, only the Per- 

 mic, the Siluric and Ordovicic are unrepresented by fossiliferous 

 beds, although probably the last two occur in this vicinity. The 

 Jurassic of Martha's Vineyard is regarded by palseobotauists as 

 lower(?) Cretacean on account of its plant remains. The accept- 

 ance of the Jurassic age of these beds rests at present upon their 

 identification by Professor Marsh with others of the Atlantic 

 coast in which he has found Jurassic Dinosaurs. 



(37) 



