302 



THE BOOK OF CHOICE FERNS. 



condensation. Some species, especially among the most dwarf-giwing kinds, 

 succeed best when established on a piece of sandstone without any other 

 material. This is a mode adopted by Mr. Ulbricht, an enthusiastic amateur, 

 of Belmont, Queen's Road, Leytonstone, who has derived great satisfaction 

 from that uncommon way of growing them, and who may well be proud 

 of the achievement, as he has proved most successful in the cultivation of 

 these his favourite plants. 



Hymenophyllums are propagated but slowly— a fact which no doubt 

 accounts for their prices remaining higher than those of ordinary Ferns. We 

 have known only one batch of young seedlings, and these, even when five years 

 old, did not show their true characters. The plants are, however, commonly 

 increased by the division of their rhizomes, an operation which is safe enough, 

 although it is one requiring a little patience. Draughts must be carefully 

 avoided at all times of the year, and air should only be very sparingly 

 admitted into the case. 



Principal Species and Varieties. 



H. abruptum— ab-rup'-tum (abrupt), Hooker. 



This lovely, dwarf-growing species, also known as H. brevifrons, is a 

 native of Jamaica, Cuba, Yenezuela, and Brazil, growing on trunks of trees 

 and rocks, which it densely covers, and to which it gives quite a mossy 

 appearance. Its delicate little fi'onds, seldom more than lin. long and Jin. 

 broad, are borne on very slender stalks |in. long and of a wiry nature ; they 

 are pixmatifid (di^dded half-way to the midrib), glossy, and of a curving 

 habit. The sori (spore masses), one or two to a frond, are terminal on the 

 upper leaflets, and provided with an involucre (covering) that is divided not 

 more than half-way down, with a wedge-shaped base and rounded valves. — 

 Hooker, Sj^iecies Filicum, i., p. 88, t. 31. Nicholson, Dictionary of Gardening, 

 ii., p. 165. Lowe, New and Rare Ferns, Addenda, p. 181. 



H. aeruginosum — a3r-u-gin-o'-sum (verdigris-covered), Carmichael. 



A well-marked, distinct species, native of the Island of Tristan d'Acunha, 

 where it is found pendent from rocks and trunks of trees. Its pretty fronds. 

 (Fig. 79), at all times covered with a whitish pubescence (down), are 



