Ill] 



THE BRACKEN^ FERN 



35 



'**^^?^,r 



-^^(^3^ . 



Fig. 5. Leaf of the male Shield-Fern {Nephrodiwn Jilix-mas, Kieh.), 

 about one-eighth natural size, the lower part having the under 

 surface exposed. To the left a single segment, bearing the sori, 

 each covered by its kidney-shaped indusium. (After Luerssen.) 



3—2 



