146 BOTANY. 
sult of their coming together is the fertilization of the germ- 
cells, and their transformation into resting spores by the 
secretion of a wall of cellulose on each one. 
300. In germination the resting spore lengthens and un- 
Fic. 73.—Sexual organs of Rockweed (F. vesiculosis). A, antherids; B, an- 
therozoids; I, odgone and hairs; IJ, escape of germ-cells; IZ, germ-cell sur- 
Tpunted. oy palherozcids; IV, V, germination of resting spore. Magnified 160: 
Imes; B, . ai 
dergoes division into numerous cells; at the same time it: 
elongates below into root-like processes, which serve to: 
hold fast the new plant (V, IV). 
Practical Studies.—(a) Secure specimens of Rockweeds, fresh or 
dry. Fresh ones may easily be found along the beach of the ocean: 
after a storm. Dry specimens can easily be procured by purchase or 
exchange. Make thin cross-sections through the conceptacles in the- 
thickened ends of the branchlets. When mounted in water, even: 
the sections from the dry specimens will frequently show the sexual! 
organs quite well. It must be remembered that some species are: 
dicecious, i.e., have the antherids on one plant and the odgones on: 
another, 
