CLASSIFICATION. 





[c] Eeceptacles local, &c., continued. 



(2) Sori parallel with the venation, &c.,cow&werf. 



(b) Sori indusiate, dorsal on the veins ; on a 

 cristseform receptacle ; indusium double, 

 opening in opposite directions ...... 



(c) Sori naked or spuriously indusiate, dorsal 



on the veins. 



(a) receptacles linear, variously reticulate- 15. 



anastomosed ............ Hemionitideae. 



(J) receptacles linear, simple or forked, 16. 



(sometimes short linear, i.e., oblong) ... 



(c) receptacles oblong, contiguous, parallel, 

 the spore-cases becoming confluent and 

 simulating a broad marginal sorus (spu- 

 riously indusiate) ......... 



(3) Sori punctiform, (rarely in 18, sub-oblong, 



or by confluence more or less elongate). 



(a) Sori naked, i.e., without true indusia ; 



(fertile fronds sometimes contracted with 18. i 



involute margins=spuriously indusiate). PolvpodieSB. 



(b) Sori indusiate, i.e., with superior indusia. 

 (a) Indusium reniform or peltate, attached 



by the sinus or centre, free at the mar- 

 gins, (fertile fronds sometimes involutely 

 contracted) ............ 



(i) Indusium rotundate, attached trans- 

 versely to the vein by its base, the mar- 



gins free ............... 



(c) Indusium roundish or oblong, adherent 

 at the base and margins, opening in front, 

 i.e., exteriorly ............ 



(c) Sori involucrate, i.e., with inferior indusia. 



(a) Special indusium more or less adherent 

 to and connivent with the margin of the 

 frond, forming an entire or two-valved 

 cup; sori therefore within a marginal cup 



(5) Indusium or involucre distinctly within 

 the margin of the frond, forming an entire 

 lobed or fimbriated cup ; sori therefore 23. 



within a dorsal cup ......... Peranemese. 



AspidieSB. 

 20- 



Cystopteridese, 



DavallieaB. 



