Plate XXIX. 



Fig. 108. Selaginopsis triserialis. 



A. Natural size. 



B. C. Portions of branches showing arrangement of hydrothecse. 



Fig. 109. Sertularella albida. 



A. Natural size. 



B. Portion of branch showing hydrothecœ. 



C. Gonangium (After Nutting). 



Fig. 110. Sertularella conica. 



A. Natural size. 



B. Portion of stem showing hydrethecse. 



C. Gonophores 



Fig. 111. Sertularella pedrensis. 



A. Natural size. 



B. Portion of stem showing hydrothecse. 



C. Gonangium (After Torrey). 



