COAL ROCKS OF EASTERN VIRGINIA. 313 



in the larger pinna above mentioned, is about one tenth of an 

 inch across. The leaflets are attached to the mich-ib by their 

 whole base, and where they unite with it are nearly in contact 

 one with another, but not confluent. They are about one tenth 

 of an inch wide, preserve a nearly uniform breadth from the base 

 outward, and are bluntly rounded off" at the extremity. They are 

 from one to two inches long, becoming shorter towards the upper 

 end of the leaf, and are either straight or slightly falcated. From 

 the lower end of the leaf to near the upper, the pinnules are 

 placed at an angle of from seventy to eighty degrees with the 

 midrib ; at the upper end they make a more acute angle. Each 

 pinnule is marked by from tliree to sLx parallel veins, springing 

 from the midrib, and running to the extremity. As yet I have 

 met with no specimen exhibiting the stem and pinnae in connec- 

 tion, and I am therefore unable to speak of the character of the 

 stem to which these leaves belong. 



On comparing this fossil with the figures given by Professor 

 Phillips, and by Lindley and Hutton, of the several species of 

 Cycadites or Pterophyllum^ found in the Oolite rocks of York- 

 shire, &c., it will be found, along with a marked general resem- 

 blance, to present several striking peculiarities. Nor does it bear 

 even as near a specific analogy to the other fossils of the same 

 tribe, figured and described by Sternberg. 



The fossil which it most closely resembles is one which I find 

 figured among the illustrations of Captain Grant's interesting 

 ' Memoir on the Geology of Cutch,' (Geol, Trans., vol. 5,) 

 under the title of " Ptilopltylhim acutifoliumP In the latter, 

 however, the leaflets have an " acute apex," and are " imbricated 

 at the base, and attached obliquely," in all of which characters it 

 differs from the Virginia fossil. 



In accordance with the generic characters which appear to 

 have guided Prof. PhiUips, this fossil would rank as a Cycadites, 

 while in obedience to the definition of Brongniart, and Lindley 

 and Hutton, it should be placed in the genus Pterophyllum. 

 Preferring what appears to me the simpler arrangement of the 

 Cycadites adopted by Sternberg and Presl, I have rather 

 chosen to place it in the comprehensive genus Zamites of the 

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