382 



FIUCALES 



[CH. 



The restoration, after Nathorst', shown in fig. 281 illustrates 

 the habit of this striking fern, examples of which or of closely 

 allied species are recorded from Rhaetic rocks of Germany, Scania, 

 Persia, Bornholm, Tonkin, China, and elsewhere^ The petiole, 

 reaching a length of 60 cm., forks at the apex into two equal 

 arms leaving between them an oval space and occasionally 

 crossing one another. The axes of these branches are twisted 

 so that the pinnae, which may be as many as 24 on each arm, 



Fig. 282. A. BicUjophyUum Nilssoni. 



B. Rhizomopleris Schenki. 



C. Cavtptopteris spiralis. 



D. E. Dictijophylliim exile. 

 (After Nathorst; A, B, C, E, | nat. size.) 



and arise from the inner side, by torsion of the axes assume an 

 external position. An interesting analogy as regards the 

 twisted rachis of Dictyophylluvi exile and Camptopteris is 

 afforded by the leaves of the Cycads, Macrozamia Fawcettiae and 

 M. coralUpes, which are also characterised by the torsion of 

 the rachis. The habit, justly compared by Nathorst with 



Nathorst (06^). 



2 Seward and Dale (01) p. 505. 



