10 



I. CYATHEACEAE. 



h.h.h. Indusium spurious, consisting of a minute scale placed at t^ 

 inner side of the receptacle Or of a circular, entire cuHiobed 

 scale or a whorl of fihres with the receptacle inJJre centre. 



Ng,..-S''^A.lsopliila. 



«.«. Sori exindusiate. ^^^^^o. 3. AljSophila. 



•i-.f. Sori terminal on the veins. ^^ DICKSONIEAE. 



*. Indusium 2-valved, the oujjM^valve consisting of an Ulunodified, 



cucullate lobe of the,fe^d, forming with the inner valve a saccate 



involucre to th^^-«^s. No. 4. Dicksonia. 



*.». Indusium.,.'^alved, the outer valve like the inner one, distinctly 



(Mfe^tiated from the margin of the frond, both forming a saccate 



^'^nvolucre to the sorus. No. 3. Cibotium. 



