CHAP. III. 
MOSSES. 
265 
in Salvinia, to communicate laterally with the case. The 
other involucres, which are supposed to be male organs, have 
a very complex structure, and have been well observed by 
Brown. In Salvinia they contain a great number of spherical 
granules, attached by long pedicles to a central column : these 
granules are much smaller than the grains ; their surface is 
reticulated in like manner, and they do not burst by the 
action of water. All the species are floaters, and their leaves 
are not gyrate when developing, but are more like those of 
Lycopodiaceae. Thus far Brongniart ; see also Martius, 
/c. PL Crypt Bras., for many curious additional observations. 
With respect to the nature of these two kinds of grains or 
granules, it has been thought, as is obvious from the foregoing 
remarks, that the smaller are males and the larger females ; 
which has been supposed to be proved by the experiments of 
Savi of Pisa. This observer introduced into different vessels, 
1. the granules; 2. the grains; and, 3., the two intermixed. 
In the first two nothing germinated ; in the third the grains 
floated to the surface and developed themselves perfectly. 
These observations have, however, been repeated by Duver- 
noy without the same result. But M. Fabre’s observations 
upon Marsilea seem to leave little doubt about this order 
having reproductive organs analogous to sexes. 
5. Mosses and Andrceacece. 
In the structure of these plants neither vessels nor woody 
tissue are employed ; and henceforward those organs dis- 
appear from the structure of all the orders to be noticed. 
Their stem consists of elongated cellular tissue, from which 
arise leaves composed, in like manner, entirely of cellular 
tissue without woody tissue ; the nerves, as they are called, 
or, more properly speaking, ribs, which are found in many 
species, being formed by the approximation of cellules more 
elongated than those which constitute the principal part of 
the leaf. The leaves are usually a simple lamina ; but in 
Poly trichum and a few others they are turnished with little 
plates called lamellae, running parallel with the leaf, and ori- 
ginating in the upper surface. 
