192 
Choice Ferns for Amateurs. 
only four species and a few varieties, is nevertheless 
very interesting, inasmuch as, with the exception of 
the essentially North American C, bulbifera, all 
others are indigenous to this country, and well 
adapted for planting in the outdoor Fernery, where 
shady and well-drained spots should be selected for 
them, all being found growing" naturally at high 
elevations. With the exception of C, montana, 
which is provided with underground creeping 
rhizomes, all the Cystopterises produce their slender 
fronds in great abundance either from a closely- 
tufted crown or from shortly-decumbent rhizomes. 
On account of their delicate appearance, all are well 
adapted for pot-culture, either under glass, in a 
cold frame, or without glass protection, in a 
sheltered position. All the known species and 
varieties lose their fronds early in the autumn, and 
remain dormant until about April, during which 
period their crowns must not be allowed to get com- 
pletely dry. When planted out, a compost of about 
equal parts of fibrous peat, loam, and leaf mould is 
best. For pot-culture it is advisable to add to this 
mixture a small proportion of old, crumbled mortar 
or broken limestone, and also to pay special attention 
to the drainage. Bladder Ferns are usually pro- 
pagated during March and April by division of the 
crowns, wherever more than one has formed; they 
are also easily raised from spores sown in autumn in 
a cold frame. C, bulbifera, however, is more readily 
increased by means of the bulbils produced along the 
stalks of the leafy portion of the frond, which, 
having fallen to the ground, soon emit a few slender 
roots and send up some rudimentary fronds, pro- 
ducing perfectly-developed foliage during the second 
year. 
C, bulbifera. 
This singular and elegant species, which takes its name 
from the large^ fleshy bulbils borne on its upper leaflets, is 
a very distinct plant, of North American origin, and quite 
as hardy as any of the British species and varieties. The 
fronds are of a thin, papery texture, and yet not without 
a kind of brittle rigidity; they are produced from a root- 
stock that is usually quite short, seldom over lin. long, 
