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THE BOOK OF CHOICE FERNS. 



The extremely curious West Indian Acrostic! turn (Hymenodium) crinitum, 

 popularly known, on account of its peculiar shape, and also of its extraordinary 

 texture, as the Elephant's -ear Fern, is undoubtedly one of the greatest curiosities 

 in the whole order. The barren fronds, which are produced from a woolly 

 and somewhat decumbent rhizome, are simple and entire, progressively attaining 

 larger dimensions, until they ultimately measure about IJft. in length and 

 lOin. in breadth at their widest part. The whole of their surface, as well as 

 their margins, is covered with long, black, stiffish hairs, which give the plant 

 a most peculiar appearance ; they are borne on stalks varying from Gin. to 

 Sin. long, also densely covered with the same long, black hairs. The fertile 

 fronds are much smaller in all their parts than the barren ones, besides being 

 contracted, and borne on shorter stalks. This strange plant, as well as the 

 dwarf and elegant A. (Rhipidopteris) peltatum, whose fronds, several times 

 dichotomously divided, and showing very narrow linear divisions, are disposed 

 on slender, creeping rhizomes, are as different from other Acrostichums as 

 possible, and anyone may readily be excused for not taking them at a first 

 glance as belonging to the Fern order. 



Certain Polypodiums, such as P. {Pleopeitis) fossum and P. Xiphias, and 

 the Australian Gymno gramme Muelleri, are so many other instances illus- 

 trating the great diversity in habit or in shape of foliage existing between 

 some species and that of the majority of their congeners. The Floating 

 Stag's-horn (Ceratopteris thalictroides) bears very little resemblance to a Fern ; 

 and all the Marattias — those giants of the non-arborescent Fern vegetation — 

 have very little besides their mode of fructification to make them rank with 

 ordinary Ferns : yet such they undoubtedly are, the Marattias forming one of 

 the most conspicuous and well-marked genera of the whole order. 



The exceedingly curious Botrychium Lunaria, or common Moonwort, and 

 the no less peculiar Ophioglossum vulgatum (Adder's-tongue), are two very 

 striking examples of cosmopolitan and British Ferns which, from their appear- 

 ance only, would be precluded from belonging to the order. Both plants 

 produce only solitary fronds, and those of a most peculiar conformation. The 

 former, whose usual habitats are mountain meadows and pastures, though by 

 no means common, is nevertheless found in various parts of England, Scotland, 

 and Ireland. Its crown is composed of a slender tap-root, producing a simple, 

 cylindrical, erect, pale green stem, from the middle of which issues a solitary 



