226 ELEMENTS OF BOTANY. 
tained in the expanded portions, f. In these expansions 
there are produced somewhat spherical bodies, A, Fig. 197, 
which may be called egg-cells (odspheres), and ciliated fertil- 
izing cells, or antherozoids, G. After the bursting of the 
thin membrane, shown at A, by which the egg-spheres are 
confined, they become covered with multitudes of the fertiliz- 
ing cells, as seen at F# and H, and are often whirled about 
by the motion of the cilia of these cells. At length, the sub- 
Fie. 197. — Production of Spores of Rockweed. (Much magnified.) 1 
A,abundle of egg-spheres, or odjspheres (from interior of f, Fig. 196); G, ciliated 
fertilizing cells, or antherozoids (from interior of f, Fig. 196); F, H, egg-spheres 
changing to spores by union of fertilizing cells with their contents. (G is magni- 
fied more than twice as much as the other parts of the figure.) 
stance of one of the ciliated cells becomes mingled with that 
of the naked protoplasmic egg-sphere, and the latter soon 
proceeds to develop a cell wall and begins at once to grow 
into a new plant of rockweed. 
THE STUDY OF YEAST. 
276. Growth of Yeast in Dilute Syrup. — Mix about an eighth of a 
cake of compressed yeast with about a teaspoonful of water and stir until 
a smooth thin mixture is formed. Add this to about half a pint of water 
in which a tablespoonful of molasses has been dissolved. Place this mix- 
1A and F of this figure represent the spore-producing apparatus from Fucus 
platycarpus. Fig. 196 is Fucus vesiculosus. The principle of spore-formation is very 
similar in the two species. 
