THE MARINE BOTANIST. 191 



GENERA OF THE CRYPTONEMIA 

 TRIBE. 



Grateloupia. Frond pinnated, flat, narrow, between 

 membranaceous and cartilaginous. Structure 

 very dense. Favellidia in the branches. Tetra- 

 spores scattered. 



Gelidium, Frond pinnated, compressed, narrow, 

 horny. Favellidia in swollen ramuli. 



Gigartina. Frond cartilaginous, cylindrical, or 

 compressed. Favellidia in external tubercles. 

 Tetraspores sunk in the frond. 



Chondrus. Frond fan-shaped, dichotomously cleft, 

 cartilaginous. Tetraspores in sori immersed in 

 the frond. 



Fhyllophora. Frond stalked, rigid, membra- 

 naceous, proliferous from the disk. Tetraspores 

 in sori or in proper leaflets. 



Peyssonelia, Frond depressed, expanded, rooting 

 by the under surface. 



