220 



THE SPORE-PRODUCING ORGANS 



[CH. 



» 



Fig. 213. A, B = Young leaves oiSchizaea riipestris, showing circinate vernation, 

 with the pinnae reflexed to the convex (abaxial) side. ( x 3.) C, D, ^ = Trans- 

 verse sections of very young pinnae of Schizaea rnpestris, showing the mar- 

 ginal origin of the sporangia, which are very soon turned towards the lower 

 (abaxial) surface: in D, E the indusial flaps are appearing, right and left; 

 F, 6^= Similar sections of older pinnae, with sporangia and indusia more 

 advanced. ( x 60.) 



Fig. 214. Longitudinal section through the apex of a pinna of 

 Mohria caffrorum, showing the apparently superficial position 

 of the sporangium, which is actually marginal in origin. This 

 appearance is due to the active growth of the indusium from 

 its base, forming a false margin. ( x 75.) 



