314 



CASSELL'S POPULAK GARDENING. 



bulbous plants require great attention, for if they 

 suffer from undue dryness or excessive wetness they 

 are much checked. They require to be grown on 

 steadily fronj the infant to the adult stage without 

 protracted seasons of rest, which mature bulbs re- 

 quire. 



Offsets and bulblets, like those produced on Tiger 

 LQy stems, need the same careful attention, as they 

 do not possess the same power of enduring rough 

 treatment as adult bulbs. Seeds of bulbs vary so 

 much in character, that no general rule can be given 

 as to the depth they should be sown and other spe- 

 cial treatment they require. These will be alluded 

 to under the genera. 



FERNS. 



By Jahds Beitten, P.L.S. 



The Cystopteris, or Bladder IPerns. — Taking 

 the standard of specific rank adopted by the authors 

 of the " Synopsis Filicum," there aje three of the 

 five known species of Cystopteris represented in the 

 British flora. All are deKcate, flaccid, deciduous 

 ferns, with small, twice or thrice-divided, thin green 

 fronds, and free veins. Amongst ferns this genus is 

 exceptional in its geography on account of its head- 

 quarters being in. the temperate zones of both hemi- 

 spheres. The name Cystopteris was given on account 

 of the bladder-like involucres. 



C. alpinum, a very elegant little plant, has only 

 recently been thoroughly settled as a truly British 

 species, it having been discovered in Teesdale by Mr. 

 Backhouse. In the other localities whence the 

 plant was obtained it was doubtfully native, or 

 finely-cut forms of C. fragilis had been taken for it. 

 The finely-cut bright green fronds generally are 

 about four to six inches high. The extra-British 

 distribution is the mountains of Europe and Asia 

 Minor. 



C. bulliforum takes its name from the large fleshy 

 bulblets which are formed in the axils of the upper 

 pinnse ; these fall to the ground and often produce 

 new plants. This species is the largest of aU the 

 Cystopteris ; its lanceolate, elongated, twice-cut fronds 

 sometimes attain — in shaded ravines in the United 

 States — as much as a couple of feet in length. 



C. fragilis, a native of arctic and north and south 

 temperate regions, varies considerably both in the 

 size and cutting of the fronds ; three or four more or 

 less well-marked varieties occur in Britain and have 

 received distinctive names. It has a tufted root- 

 stock and ovate-lanceolate, pale green, once or twice- 

 pinnate fronds four to eight inches long. 



C. montanum, one of the rarest of our native ferns, 

 has a creeping root-stock, veiy slender stipes, and 

 deltoid thrice-pinnate fronds as broad as long (four 

 to six inches.) In Britain it is found only on the 

 mountains of Perth, Forfar, and Aberdeen, at eleva- 

 lons of from 2,300 to 3,600 feet. 



Cultivation. — "With the exception perhaps of 

 C. bulbifenm (which, however, succeeds in the open 

 air in some localities), the species above described 

 are quite hardy. C. fragilis and alpinum do well in 

 rock- work, and not unfrequently establish themselves 

 readUy on old shaded walls. C. montanum, in its 

 native habitats, affects damp moss-covered ledges, 

 the creeping rhizomes finding a congenial home 

 imongst the shcrt scanty plant-growth of the moun- 

 tain-sides ; it requires more moisture than the other 

 species enumerated, but is easily grown if shade and 

 moisture be forthcoming ; we have seen plants grown 

 under a glass case in a crowded city thoroughfare, far 

 surpassing in size and beauty any of those noticed in 

 the very locality whence they were originally pro- 

 cured. C. bulhiferum is a pretty cool-house plant, and 

 only requires a well-drained situation and a mixture 

 of loam and leaf -mould in which to make itself per- 

 fectly at home. If grown in pots this and the others 

 ■ — with the exception of C. montanum — only require to 

 be guarded from excessive moisture during the winter 

 months, when the fronds have died down and the 

 plants are at rest. 



Tile "Woodsias. — About fourteen species of 

 Woodsia are known, and of these about half are 

 in cultivation. Our two British species are grown 

 more on account of their rarity and the almost 

 inaccessible places in which they occur than from 

 their beauty. Some of the exotic species are larger 

 and more easily cultivated than our native ones. 



W. hyperborea has linear-lanceolate fronds with 

 ovate-cordate pinnae and few broad lobes. In its 

 distribution it is similar to TV. Ilvensis. 



W. Ilvensis has broadly-lanceolate pinnate fronds, 

 two or three inches high, of a dull green colour, both 

 surfaces being clothed with minute bristle-like scales. 

 The American form of this species — for it occura on 

 high mountains in the temperate zone of the Northern 

 Hemisphere, as well as in arctic regions — is a much 

 more vigorous one than the British. 



W. Oregana has densely-tufted chestnut-coloured 

 stipes two to four inches long, and oblong-lanceolate 

 bi-pinnate fronds three to four inches long, narrowed 

 to both ends. It differs markedly from the species 

 already described in its glabrous fronds and minute 

 involucre. A native of the Eocky Mountains, Oregon, 

 and Lake Winnipeg. 



W. scopulina has densely-tufted" stipes two t» 

 three inches long, with large lanceolate scales and. 



