BRYOPHYTA. 189 
cells extending from the leaves to the bundle in the stem. 
It cannot be doubted, then, that the Mosses possess rudi- 
mentary fibro-vascular bundles. As in liverworts, the tis- 
sues of mosses develop from a single apical cell. Breathing- 
pores resembling those of the higher plants occur on the 
spore-fruits; they are not found upon the leaves or stems. 
895. Mosses, for the most part, grow upon moist earth 
or rocks, or upon the sides of trees; : 
comparatively few are aquatic. 
They range in size from less than a 
millimetre to many centimetres in 
length, the most common height 
being from two to four centimetres. 
They are all chlorophyll-bearing 
plants, and are generally of a bright- 
green color; occasionally, however, 
they are whitish or brownish. 
396. The reproduction of mosses 
is mainly sexual, but occasionally 
buds are found resembling those of 
the liverworts. The sexual organs 
develop either upon the end of the 
stem, within flower-like rosettes of 
leaves, or in the axils of the leaves. 
The antherids are club-shaped or 
globose trichomes (Fig. 105), whose , #1¢. 105.4. an antherid of 
a Moss ruptured, showing 
: . . the mass of sperm-cells, a—. 
interior cells (sperm-cells) produce magnified 350 times; "b, a 
. orm - cell, i 
antherozoids. Thesperm-cells, when fines, otis aaibeneeud. 
mature, escape from the antherid “™°?*°'s f°. 
through a rent in its wall. Each sperm-cell contains one 
spirally coiled antherozoid, which, when set free, swims by 
means of its two long cilia (Fig. 105, c). 
