112 THE OLDER MESOZOIC FLORA OF VIRGINIA. 



Pterozamites pectinatus. 



Plate LIU, Fig. 4. 

 Emmons's "Am. Geol.," p. 117, fig. 84. 



"Leaves narrow, many nerved, and standing at right angles to the strong mid- 

 rib. Occurs at Lockville in the blue slate." 



This plant bears a strong resemblance to Pterophyllum Lyellianum 

 Dunker, from the Wealden of Germany; at least it resembles the forms of 

 that plant with narrow leaflets. Compare Schenk, "Foss. Flor. der Nord. 

 Weald.," plate xiii, fig. 1, and Dunker, "Monographic der Nord. Weald.," 

 plate vi, figs. 1, 2. It-is, however, apparently a new species, and may be 

 called Pterophyllum pectinatum, for it is clearly a true Pterophyllum. 



Pterozamites obtusifolius (Zamites obtusifolius Rogers.) 



Plate LIV, Fig. 4. 

 Emmons's "Am. Geol.," p. 118, tig. 85. 



"Midrib straight, tapering to the end of the pinna, striate; leaflets attached by 

 their whole base, and nearly in contact, and standing upon the stem at angle of about 

 80°. Pinnules have from 3 to 6 parallel veins." 



Emmons goes on to say of this plant : 



" I have observed many specimens at Haywood which agree in size and other char- 

 acters with the foregoing. Generally the apex of the leaflet is rounded off in the same 

 manner, but in some specimens it is more tapering, and may appear more acute. In 

 others still, which perhaps should be referred to this species, the leaflet is about one- 

 tenth of an inch wide, and preserves this width to near the apex, and the leaves are 

 also shorter. Fig. 85 [Plate LIV, Fig. 4, of this work] is an example of a common 

 form. The figure is taken from the middle of a frond." 



He seems to be uncertain whether to refer the plant to Rogers's Zam- 

 ites obtusifolius or not, stating that they frequently appear to run into each 

 other. 



The plant in question is clearly the var. /3, or the form with short leaf- 

 lets of Ctenophyllum Braunianum Goepp., from the Rhsetic of Franconia. 

 Compare figs. 1, 2, plate xxxviii, Schenk, "Foss. Flor. der Grenszchichten." 

 Emmons does not give the exact horizon at Haywood on which the plant 

 is found. From his remarks it would appear that the fossil is abundant. 

 We thus have in North Carolina and in Virginia both varieties, and in 

 abundance, of this plant which is so highly characteristic of the Rhsetic 

 formation. 



