164 



BRITISH FERNS 



Lastrea Thelypteris (The Marsh Buckler Fern) 



(Plate XX) 



This species is the only British one which actually grows in 

 boggy, water-logged soil, and it differs widely from the other 

 Lastreas in forming no definite crown, but in having a thin, creeping 

 rootstock, almost on Polypody lines, these forming mat-like masses, 

 whence the long, slenderly made fronds spring singly. These 

 fronds (Fig. 183) are erect, and have very long, naked stalks, bearing 

 somewhat distant pinnae, very much on attenuate L. montana lines, 



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Fig. 183. L. thelypteris (pinna). 



but without the short lobes commencing near the base which are 

 characteristic of that species. They are of a delicate green, and tall, 

 attaining in favourable situations over a yard in height. Its 

 culture is easy if boggy, peaty conditions and plenty of moisture 

 be provided. We produced a rampant specimen by planting a 

 piece of the creeping caudex in peaty soil, over a good-sized glazed 

 earthenware pan sunk in the ground and filled with pieces of 

 broken brick, over which moss was laid to prevent admittance of 

 the soil. Every rainfall or watering was caught by this pan, and 

 obviously the roots proper of the thirsty Fern obtained admission 

 to this supply, for the creeping rootstocks spread, and even emerged 

 in all directions, and had eventually to be drastically checked to 

 prevent monopoly of valuable space. Peaty soil, in pans, kept well 

 watered, suits the Fern admirably, though owing to its tall growth 

 and slender stalks it does not rank among the decoratives. No 

 variety has been found in this country, but a very good crested 

 form, L. t. -polydactyla (Puffers), was found some years ago by a 

 lady in the United States, and figures in our collection as, if not 

 a British find, at any rate a " sport " of a British species, and there 

 are some very promising grandicefis forms raised by the writer. 



