EXPLANATION OF PLATE XVIII. 



CAMPTOSORUS. Plant of C. rhizophyllus, and (1) a portion of a frond, 

 with fruit-dots, enlarged. 



SCOLOPKNDKIUM. Tip of a fertile frond of 8. vulgare ; and (2) a piece 

 enlarged, with two fruit-dots. 



ASPLENIOI. (1) A pinna of A. thelypteroides; and (2) part of a lobe in 

 fruit, enlarged. 



DICKSONIA. (1) Pinna of 1). pilosinsrnla ; (-2) portion of a pinnule, en- 

 larged; and (.'!) a fruit dot in its cup-shaped indttsium. 



