CHARACTERS, DISTRIBUTION, ETC., OF FERNS. 
110 
size. In a fossil state tliey are found in almost every one of the lower strata of our globe ; 
they are especially numerous in the coal strata and the contiguous beds of shale ; 
from the numbers there found m proportion to those of other species, it would almost 
lead to the conclusion that, at that age of the world's existence, they would constitute 
nearly four-fifths of its vegetation. These numbers, however, gradually diminish as we 
ascend to more recent strata, and they likewise diminish in size, and are found in much 
less perfect forms. Some of the early ones are extinct species of genera at present in 
existence, but others are of entirely new forms, by no means corresponding in their 
characters with any of the kinds at present known in a living state. All the present 
existing kinds, however, are comparatively diminutive, which shows it probable that in 
those epochs of geology, when they grew to so enormous a size, the atmosphere must have 
been far more humid, and the temperature much higher than even that of the tropics in 
the present day, for the species never luxuriate but in warm, damp, and shady situations, 
and cannot flourish under different conditions. 
The frondose leaves, for the most part, contain an astringent mucilage, with more or 
less of aroma ; several on this account are thought to be useful in medicine, amongst which 
may be named Adiantum pedatimi, A. Ccqnllus Veneris, A. melanocaulon, and Cibotium 
Barofiietz. Some are used for food — amongst these may be mentioned Nephrodium escu- 
lentwn, the rhizomes of which are cooked and eaten in Nepal ; and in other countries 
many others are used. In New Zealand the roots and lower parts of the stems of Cyathea 
medidlaris (a tree Fern), are baked by the natives, who esteem them as nearly equal to sago. 
The natives of Palma, and Gomera, in the Canary Islands, employ the roots of Pteris 
aquilina (our common Brake) for food ; they are first dried, then ground, and mixed with 
barley meal, and when boiled the mixture is called " Gofio." The roots of Pteris escu- 
lenta{fig.f)wcG eaten in New South Wales, the rhizomes are roasted and peeled, when they 
form an excellent condiment for meat ; they are also said to form a good food for pigs, 
giving a peculiar pleasant taste to the bacon ; the plant is known as the Tasmanian Fern. 
The fronds of Pteris aquilina and Aspidvmn Filix-mas are good substitutes for hops in 
the manufacture of beer, containing both tannin and gallic acid. The fronds are also useful 
for packing apples and pears ; and when burnt, the ashes contain a large proportion of 
alkali, which is used for making soap and glass; and the Wall-Fern, Polypodmm vidgare 
[fig. c), is made use of for the same purpose. The Angiop)teris evecta, one of the tree Ferns, a 
native of the Sandwich 
Islands, is employed along 
with Polypodium pliyma- 
todes, or red Polypody, in 
preparing and giving fra- 
grance to the Cocoa-nut oil ; 
and the former is also used 
as an article of food, which 
the Saudwichers call "Me- 
hai." The tubes of the pipes 
of the negroes in Brazil, are 
made of the stalks of Mer- 
tensia dichotoma, which they 
call " Samarbaya." The 
leaves of Asjyidmm fragrans 
have a peculiar, but pleasant 
odour, and have been substituted for tea. The whole plant of Aneima tomentosa emits a 
fragrance resembling Myrrh ; and Mohria thurifera smells like Laurus Benzoin. The 
large fronds of Asplenium lucidum are used in some of the Polynesian Islands as emblems 
of sorrow, and are carried in funeral processions by mourners. 
Polypodium piloselloides (fig. d), and several others, are creepers, with slender hairy 
rooting stems ; the first is an excellent plant for covering Orchid blocks or baskets, the 
leaves being small, and the stems adhering firmly by their rootlets without any dif&culty. 
