Cassells European Ferns 
Vir.-enr: Bruciks Day & Sari 
CYSTOPTER I S. (TH L BLADDER FERN.) 
I. CYSTOPTER IS FRAGILIS 2 CYSTO PT E R I S SUOETICA 3 CYSTOPTERIS MONTANA 4 CYSTOPTERIS ALPINA 
(natural size 
I* 2* 3* 4 A UNDER SIDE OF PINNULE IN FRUIT (FOUR TIMES NATURAL SIZE I 
