CULTIVATION 
1.5 
used to grass fires and recover in one season. The kinds 
differ in their individual requirements, and will be referred 
to separately further on. 
5. Rock Ferns. There are many such, which growing on 
rock debris or in cracks in rocks, are not easily supplied with 
similar conditions under culture. Usually they stand sun 
well, and are accustomed to be burned off annually or occa- 
sionally, without injury to the crown and roots. In cultivation, 
a sunny rockery with more stone than soil meets their case, 
if attention is given to keep the stones moist. 
6. Soil Ferns, standing exposure. — There are a good many 
of this class, mostly easy of culture, but some are fastidious 
and require constantly moist spots, while one requires almost 
saline conditions, and then is not pretty. 
7. Epiphytes. — Several species usually occur as epiphytes, 
and seldom are happy elsewhere. These are rather difficult 
to cultivate, since they do better on a living tree than on a 
dead one, but if established among living moss or on a mossy 
brick they do reasonably well. All these enjoy forest moisture, 
but like epiphytal orchids, they frequently occur on high bare 
tree-trunks where sunshine is abundant. 
The different habitats and conditions of growth already 
indicated give a guide to the cultural conditions most likely to 
produce health and vigour in any one species, still as each has 
its own peculiarities these will now be taken more in detail. 
GLEICHENIA. — There are three species, viz., G. polypo- * 
dioides , G. umbraculifera , and G. linearis , more or less similar 
in nature, and requiring the same conditions. G. polypodioides 
usually occupies the moist banks of running streams or water- 
falls ; the other two occupy steep slopes facing away from the 
sun, but are usually fully exposed to light, and enjoy cool 
moist conditions, usually on stiff moist soil, but where water 
cannot become stagnant. In Europe, under artificial con- 
ditions, these Gleichenias are considered the most difficult 
ferns to keep permanently in good health, and healthy 
