364 REPRODUCTIVE ORGANS OF CORMOPHYTES. 
but instead of seeds, they form reproductive bodies called 
spores, Which in most cases consist of one cell, or rarely, two 
or more, with commonly one or two coats, and enclosing 
granular and other matters. The term spore is, however, 
used in a very varied sense, as our sketch of the Reproductive 
Organs of the Cryptogamia will show. As used above, it is 
intended to apply to asexwal reproductive cells. A spore having 
no embryo can have no cotyledonary body, which is an essential 
part of the embryo, consequently flowerless plants have also 
been called Acotyledonous. In germination again, as the spores 
have no rudimentary stem or root, they have commonly no de- 
finite growth, but this takes place by an indifferent extension of 
one or both of their membranes. But some exceptions are 
afforded to this latter peculiarity by certain spores which have 
on their outer membrane certain spots or pores, through which, 
in germination, little threads are protruded from an extension 
of their inner membrane. This is exactly analogous to the pro- 
duction of the tubes from pollen-cells ; indeed, in their general 
structure, spores (especially those of the Fungi, which exhibit 
the above growth) have a striking similarity to pollen-cells. It 
should be noticed, however, that spores, although so similar 
in structure to pollen, perform essentially differen’ functions. 
The threads which are thus produced by the germination of 
spores may either reproduce the plant directly, or give rise to 
an intermediate body of varying form, called the prothalliwm or 
prothallus (figs. 806 and 809), from which the fructiferous or 
fruit-bearing frond or stem ultimately springs. 
Such are a few of the chief distinctive characters of the re- 
productive organs of Cryptogamous plants. The nature of these 
organs in the different orders of flowerless plants is, however, 
so remarkable, that, in order to become acquainted with them, 
it will be necessary for us to describe the peculiarities of each 
separately. 
The Cryptogamia have been arranged, as already noticed (see 
page 11), in two great divisions, called Cormophytes and Thallo- 
phytes, under which heads we shall therefore give a sketch of 
the reproductive organs of the different natural orders or groups 
which are comprised respectively within them. 
Section 1. REPRODUCTIVE ORGANS OF CORMOPHYTES. 
CORMOPHYTES, or, as they have been also termed, Acrogens, 
have been divided into several sub-divisions, which are com- 
monly called Natwral Orders or Orders: these are the Filices, 
Lquisetacex, Lycopodiacer, Selaginellacexr, Marsileacer, Musci, 
and the Hepaticacex. These orders are differently arranged and 
defined by botanists ; but as our object is only to give a general 
sketch of their reproductive organs, we have adopted the above 
