XXVIl] TAENIOPTEEIS 487 



polygonal cells some of which are elongated at right angles to 

 the surface of the lamina. A very similar form is described 

 by Fontaine and White from the Permian of Virginia as T. 

 Lescuriana^. 



It is futile to expect to be able to separate the numerous 



Pio. 329. A. Taeniopteris vmltinervis, Weiss. (^ nat. size. After Zeiller.) 



B. T. multinervis. (Enlarged. After Zeiller.) 



C. Lesleya Delafondi. (x2. After Zeiller.) 



Taeniopteris leaves into well-defined species: all we can do is 

 to group the specimens under diflFerent names, using as arti- 

 ficial distinctions such characters as the shape of the leaf, the 

 number of veins per centimetre, and the prominence of the rachis. 

 Another Virginian species of Permian age described by Fontaine 



1 Fontaine and White (80) PI. xxxiv. 



