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roughly -broken fibrous peat and sphagnum as the plants require it. Thus 

 grown, they form a fine feature, hiding the supports, which, when naked, are 

 unsightly. Acrostichums are also useful for covering walls, in front of which 

 a wire trellis should be erected. A space of about 3rn. must be left between 

 either the wall or the column and the wire trellis, and the interval between it 

 and the wall filled with the compost named above. 



The genus Polypodium (in which are included Niphobolus, Phegopteris, 

 Phlebodium, Phymatodes, Pleopeltis, &c, of commerce) also contributes largely 

 to the section of Trailing Ferns ; for a great many of the species contained in 

 it are provided with rhizomes of an essentially trailing nature. This character 

 belongs as much to the British species Polypodium cahareum (the Limestone 

 Polypody), P. Dryopteris (the Oak Fern), P. Phegopteris (the Beech Fern), 

 and P. indgare (the common Polypody), as it does to many of the species of 

 exotic origin, either with gigantic upright fronds, as P. aureum, or with long, 

 drooping fronds, like P. ( Goniophlebium) subauriculatum, or with smaller fronds, 

 such as P. piloselloides, P. repens, P. rupestris, &c. These, and many other 

 species, too numerous to be mentioned here, may with advantage be employed 

 for the purpose of covering Tree-Fern stems, as recommended for Acrostichums, 

 Davallias, &c. They are considered all the more serviceable for that effect in 

 that their culture does not present any serious difficulties, and that among 

 them are found some species adapted for the cool -house as well as others are 

 for the stove. Their propagation is of the simplest description possible, for 

 each portion of their rhizomes (in most cases of a fleshy nature), when pro- 

 vided with two or three fully-developed fronds, readily forms an independent 

 plant if carefully separated from the mother plant. 



Gleichenias, especially those which belong to the section composed of 

 plants with orbicular segments or pinnules resembling a quantity of beads, 

 may also be classed among some of the most distinct Trailing Ferns. These 

 plants, besides being highly decorative, are of the utmost interest, inasmuch 

 as their habit, growth, and general appearance, are wholly different from those 

 of any other Ferns. Their growth, instead of being limited to the production 

 of fronds which, as in nearly all other Ferns, when once developed, remain 

 stationary, possesses an altogether distinct character. These organs, which 

 spring from thin, wiry, creeping rhizomes, are either bifurcate or dichotomously 

 divided, according to the different species. In the centre of each frond there 



