DEVELOPMENT OF PLANTS 



213 



Fig. 127. Features in the reproduction of Polysiphonia: A, branch off 

 the plant bearing clusters of male gametangia, an. B, one of the clusters- 

 enlarged, showing the numerous small gametangia. C, branch on which the' 

 spores derived from the garaetospores are enveloped by a sac. From one 

 of these bodies, called cystocarps, the spores are escaping. 



of the plant, or they may be associated in conspicuous groups. 

 The spores escape from the mother cell as naked bodies and 



Fig. 128. 



A branching filament of Callithamnion, showing the spore 

 mother cells forming tetraspores. 



