C YS TOTTER IS. 
2 I 
CYSTOPTERIS. 
ITH only one exception, the members of this small but elegant genus are 
reckoned among the ferns of Europe, and will therefore be considered in detail. 
The geographical distribution of the genus is thus exceptional among ferns, 
its head-quarters being found in the temperate zones of both hemispheres. 
C. fragilis is one of the most widely-distributed plants of the order ; the 
others are more limited in their range. The extra-European species alluded to 
above is Cystopteris bulbifera , a very distinct plant, native of North America, 
extending from Canada southward to Virginia and North Carolina. It is 
the largest of the genus, the fronds being sometimes as much as a foot in 
length, and much narrowed at the apex ; but its most characteristic feature, 
to which it owes its name, is to be found in the large fleshy bulblets 
which are formed beneath the frond in the axils of the upper pinnae. These fall to the 
ground, and form new plants, which are about two years in coming to maturity ; and the 
propagation of the species takes place to a great extent in this manner. 
All the species of Cystopteris are well worthy of cultivation. They succeed best in rather 
stiff soil, care being taken that water is allowed to rest upon the crowns during the period of 
rest. They grow well also in cocoa-nut refuse mixed with a little loam, the pot — if grown 
as pot-plants — being about half filled with loose stones, so as to secure thorough drainage. 
As a rule, they do best in shady situations. 
The name Cystopteris is formed of two Greek words, and signifies Bladder Fern, by 
which title the plants of the genus are often referred to in books ; the allusion is to the 
hood-shaped indusium, which will be fully described hereafter. 
CYSTOPTERIS FRAGILIS, Bernh. 
This is a pretty fern, of no great size, but rather remarkable for the great variability in 
the form of its pinnae. It possesses a small, short, prostrate caudex, bright-brown in colour, 
with numerous long roots, and set at the growing end with many thin ovate, acute orange 
scales toothed at the edges. The fronds are numerous, and are given off in close proximity, 
so as to appear to grow in tufts. The stipites are slender and remarkably brittle, to which 
peculiarity the plant owes its specific name, fragilis ; they are brown, and nearly bare of 
paleae, except at the very base, and are nearly as long as the leafy part of the frond ; the 
whole is usually under one foot in length, and generally only about six inches. The light- 
green delicate fronds are oblong-lanceolate or elongated, the pinnae being largest about the 
middle of the frond, and decreasing in length towards both ends. They are usually bi- 
pinnate, with the pinnae ovate in outline, and consisting of oblong-ovate pinnules, which are 
again cut into oblong obtuse segments or teeth. The sori are dorsal, small and circular, 
arranged in a row along either side on the lateral veins of the pinnule, often, however, becoming 
confluent, and covering much of the frond ; they possess a peculiar indusium, which, though it 
covers the whole sorus at first, afterwards becomes an ovate bract-like, somewhat hooded mem- 
brane attached beneath one side of it, and is at length torn and reflexed, and may even wholly 
