THE [ASPLENIA 



75 



most of our species resent, it assumes a much larger size than in the 

 open. In a vinery at Richmond we have seen a plant of it with 



fronds two feet long, forming' L a huge plant, 

 even the most vigorous plants we have 

 found elsewhere. In congenial habitats 

 it is abundant, filling the crevices on the 

 cliff rocks, and lining the roofs of sea caves 

 with rosettes of light green fronds, in posi- 

 tions where every tide must bathe them 

 in sea water, a point worth remembering 

 in its culture, which otherwise is that of 

 rock Ferns generally, though protection 

 from frost is essential in winter, and as 

 we have seen, warm greenhouse culture 

 greatly favours development. Although 

 a number of varieties have been recorded, 

 most of these are of rather indefinite or 

 erratic character, the best being — 



Imbricatum (Fig. 34), in which the 

 fronds are congested, and the pinnse over- 

 lapping. 



Plumosum. — A very beautiful, robust, 

 bipinnate form, barren and rare. 



Ramosum. — A very marked variety, with 

 branching fronds, found in Dorsetshire by 

 Mr. G. B. Wollaston. 



a marked contrast to 



Fig. 34- 

 Asp. marinum imbricatum. 



fig. 35. Asp. ruta-muraria. 

 (A young plant.) 



Fig. 3<5- 

 Asp. ruta-muraria cristatum. 



