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CHAPTER III. 
OF THE COMPOUND ORGANS IN FLOWERLESS PLANTS. 
We have now passed in review all the different organs which 
exist in the most perfectly formed plants ; that is to say, in 
those whose reproduction is provided for by the complicated 
apparatus of sexes and of fertilising organs. Let us next 
proceed to consider those lower tribes, some of which are 
scarcely distinguishable from animals, where there is no evi- 
dent trace of sexes, in which nothing constructed like seeds 
is to be detected, and which seem to have no other provision 
made for the perpetuation of their races than a dissolution 
of their cellular system. In what I may have to say about 
them, I shall not, however, do any thing more than give 
a mere enumeration and description of their organs. All 
speculative considerations are in this case left out of view : 
those who wish to be informed upon such points may consult 
the " Introduction to the Natural System of Botany." 
1. Ferns. 
Filices, or ferns, are plants consisting of a number of 
leaves or fronds, as they are called, attached to a stem which 
is either subterraneous or lengthened above the ground, some- 
times rising like a trunk to a considerable height. They are 
the largest of known vegetables in which no organs of fructi- 
fication analogous to those of phaenogamous plants have been 
discovered. Their petioles, or stipes (rachis, W. ; peridroma, 
Necker), consist of sinuous strata of indurated, very compact, 
fibrovascular tissue, connected by cellular matter ; and the 
wood of those which have arborescent trunks is formed by the 
cohesion of the bases of such petioles round a hollow or solid 
cellular axis. The organs of reproduction are produced from 
the back or under side of the leaves. In Polypodiacece, or 
what are more commonly called dorsiferous ferns, they or'- 
