§ 7. The root-stocks, stems, stalks, and rachises of Ferns 
are often clothed, especially in their youth, with a peculiar 
kind of deciduous, membranaceous, chaffy scales, which are 
decidedly hygroscopical (absorbing water), scarious, dispersed, 
or imbricated, erect, twisted, filiform, lanceolate, oval, etc., 
and of a brown, black, or yellow colour. They are called 
Paleoe , differ in size, and their edges are either entire, sawed, 
fringed, or irregularly torn. 
§ 8. The process of fecundation in this family of plants has 
been the speculative task of many naturalists. Some skilful 
hypotheses have been advanced on the subject by eminent 
authors, in order to establish sexuality amongst them ; but as 
nature has mysteries of her own to hide from mortal view, 
so these theories, however intelligent, are only to be looked 
upon as ingenious suppositions. That young Ferns may be 
reared from spores, or seeds, is sufficiently known, as well as 
that some of them are propagated by leaf buds. (. Asplenium 
gemmiferum .) 
§ 10. For the purpose of systematic classification, the 
filical tribe has been divided into sub-orders , the chief charac- 
ters of which are to be found in the construction, shape, 
dehiscence, or position of the sporidia ; the presence or ab- 
sence of an involucre , the form of the spores , the vernation, 
etc. In Hymenophyllece (small Ferns with very delicate, 
almost transparent, fronds, without stomata ), the marginal 
spore-cases are placed upon the top of an extended vein, and 
covered with a cuplike involucre, formed by the lobes of the 
frond ; while the capsules in Ophioglossece are spiked on the 
margin of a contracted leaf, possess no ring at all, and have 
a straight vernation. 
§ 11. If the graceful Fern trees of tropical or sub-tropical 
climes approach Cycadece , and remind us of the majestic 
growth of Palms , then the small order of Lycopodiacece or 
club-mosses show, in the structure and shape of their leaves, 
an affinity to the muscal alliance. These plants form indeed a 
family of their own, but are commonly classed with Ferns as 
