THE EVOLUTION OF PLANTS 595 



to the stem of [the fern] Osmunda, but when more mature 

 certain cycadean characters appear to predominate." 1 



FIG. 417. Leaf of a fern (Angiopteris evecta). (Cf. Fig. 416.) 



Its foliage and other characters closely resemble some 

 of our modern tree-ferns (Cf. Figs. 416 and 417) bul more 

 careful study of the calcified specimens of much beauty 



1 Knowlton, F. H. American Fern Journal, 5 : 85. 1915. 



