Mineralogy and Geology. 125 
In the same belt in Pennsylvania, in the vicinity of Pheenixville, 
early last spring, Prof. H. D. Rogers discovered Posidonie in great 
mbers in a fissile black slate, and on subsequent examination, the 
same beds were found to contain layers crowded with the casts of Cyp- 
ride. Along with these are multitudes of Coprolites, apparently Sau- 
rian, resembling in size and form the Coprolites found in the carbona- 
covery at various and remote points of its course of Posidoniz, Cyp- 
ridz, and Zamites, most or all of which are identical with these forms 
in the eastern middle secondary areas of Virginia and North Carolina, 
makes it extremely probable that these rocks, formerly referred to the 
New Red Sandstone, and of late more specially to the Trias, are of 
Jurassic date, and but little anterior to that of the Coal Rocks of East- 
ern Virginia. 
crustacean remains throughout the series of deposits extending from 
the base of the Permian to the lower limits of the Odlite. But on en- 
tering the latter, the Cypride re-appear, and become very abundant 
there, there being no less than twelve species known to belong to the 
lite formations of Europe. ; 
omparing the silicified wood, found in the western and eastern 
euce Huttonia. As this particular structure does not appear to have 
been met with below the Lias, and occurs in that formation, it furnishes 
another argument in favor of the Jurassic age of all these rocks 
rof. Rogers added, that he had not found in the New Red Sand- 
Stone of the Connecticut Valley either the Posidonia or Cypris, al- 
though he had met with obscure markings which he was inclined to 
refer to the latter. He had however satisfied himself that one of 
leaf of a Zamites, 
On the whole, therefore, Prof. Rogers concluded that the additional 
fossils from the coal-bearing rocks of Virginia and North Carolina 
tha: 
and there could be little doubt, he thought, that the same conclusion 
ee Would apply to the New Red Sandstone of the Connecticut Valley. 
