THE BRYOPHYTES 275 
(6) The blade, of thin-walled 
cells containing many chlorophyll 
grains. 
(ec) The border, of strengthening 
cells, some projecting into teeth. 
Draw. 
855. Minute Structure of the Gam- 
etophyte, Reproductive Portion. — 
Dissect with needles, in water, on 
a slide, the tufts of leaves found at 
the tips of some stems.!_ Note: 
(a) The antheridia, oval sacs grow- 
ing from the enlarged tips; tips of 
the stem (see Fig. 201 for a single 
one much magnified). 
(b) The archegonia, flask-shaped 
structures arising from the tip of the 
the stem (Fig. 202). 
(c) The sterile filaments inter- 
mixed with the sex organs (Fig. 
202.) Are the antheridia and arche- 
gonia of Mnium cuspidatum borne in 
the same leaf tuft or separately? 
Draw (a), (0), and (¢) in position. 
356. Minute Structure of the Spo- 
rophyte. — Procure plants showing 
sporophytes in various stages of de- 
velopment. Draw a series of these, 
attached to the tips of the leafy stems 
from which they grow. Boil some 
stems with attached sporophytes in 
five-per-cent potash solution for a 
few minutes, rinse with water, care- 
fully pull out the sporophyte from 
the tip of the gametophyte, and 
1 It will be of decided advantage also 
to study prepared microtome slides of 
longitudinal sections of these tufts. 
Fie. 200. Development of Sporo- 
phyte of a Moss (Funaria). 
A, a very early stage, showing the 
cell-divisions of the egg; B, the 
sporophyte lengthening rapidly 
and about to tear off the arche- 
gonium, which will be carried up 
as the hood of the spore-capsule. 
The base of the sporophyte is fas- 
tened to the tissues of the game- 
tophyte (leafy moss-plant), into 
which it is inserted for a consid- 
erable distance; a, archegonium ; 
g, gametophyte ; s, sporophyte. 
