288 FILICALES [CH. 



Gleicheniaceae [Oleichenia, Platyzoma (= G. microphylla)]. 



Sporangia form circular naked sori composed of a variable 

 number of sporangia, usually not more than ten and frequently 



Fig. 223. Aneimia rotundifolia. (From the Boyal Gardens, Kew. J nat. size.) 



fewer, characterised by an obliquely horizontal and almost 

 complete annulus (fig. 224, I). In some species of Gleichenia 

 (sect. Eugleichenia) the ultimate segments are very small and 



