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. 
