74 



BRITISH FERNS 



tenanted by its near relative, the Black Maiden-hair Spleenwort 



(Asp. adiantum nigrum), from which it mainly differs in the nar- 

 rower lance -shaped outline of its 

 fronds, and the somewhat different 

 cutting of its pinnae, which are more 

 regular in size. It does not lend 

 itself easily to cultivation. It partakes 

 a little of the tenderness of its constant 

 neighbour Asp. marinum, and is far 

 more common abroad in warmer 

 climates. 



Fig. 32 represents only the tip of 

 a frond. It has not been generous 

 in varieties, and although several are 

 recorded, it is so doubtful that the 

 majority of them are still in exist- 

 ence that we only mention microdon, 

 which is a very fine and distinct 

 form, imputed to Asp. marinum by 

 Moore, and thought to be a hybrid 

 by others, though probably a merely 

 plumose " sport " of Asp. lanceolatum. 

 Though apparently fertile, the spores 

 appear to be aborted. A well-drained 



compost of peat, loam, and sand (2, 2, 1) is essential, coupled with 



a mild temperature. 



Fig. 32. Asp. lanceolatittn. 

 {Tip of frond.) 



Asplenium Marinum (The Sea Spleenwort) 



(Plate VII) 



This species (Fig. 33) is very distinct from the other Spleenworts 

 by reason of the thick, leathery texture of its fronds, as also by 

 its strict confinement to the cliffs and caves of our warmer coasts, 



Fig. 33. Asp. marinum. (Part of frond.) 



or to immediately adjacent walls, practically within reach of the 

 spray. It is properly a native of warmer climes than ours, as it 

 will not stand much frost, and under warm house treatment, which 



