A TABLE OF THE GROUPS AND GENERA OF THE BRITISH 

 FERNS AND ALLIED PLANTS. 



I. PEBNS FILICES. 



Plowerless plants, bearing seed-vessels (spore-cases) on 



the backs or margins of their leaves (fronds). The 



British Perns belong to gronps which are called 



Polypodiacea, Osmundacea, and Opkioglossacea. 



i. POLYPODIACES = Perns having the leaves rolled up in a 



circinate or crozier-like manner while young, and the 



spore-cases girt with an elastic ring, and bursting in 



an irregular manner. It comprises the lesser groups 



of Polypodies, Aspidiece, Aspleniea, Pteridea, and 



Dicksoniea. 



A. POLYPODIES = Perns whose clusters of spore-cases 

 have no special membranous cover (indusium). It 

 contains the genera Polypodlum and Allosorus. 

 1. Poly podium = Dorsal-fruited Perns, with the sori 

 exposed. 



