EE VISED LIST OF MARINE ALG^. 117 



61. Spores in external warts, tetraspores cruciate 



Peyssonnelia 

 Spores in cavities sunk in the frond, tetraspores 

 zonate Hildenhrandtia 



62. Fronds tubular 63 



Fronds filamentous or slightly compressed ... 65 

 Fronds membranaceous ... ... 85 



63. Fronds brownish-purple, thick, soft, hollow, fruit 



immersed in the frond, tetraspores cruciate 



Dumontia 



Fronds more or less gelatinous, compressed or 

 cylindrical, branches much contracted at the 

 base, often constricted at intervals with pseudo- 

 articulations, tetraspores tripartite 64 



Fronds purple or nearly black, constricted at 

 intervals, tetraspores zonate Gatenella 



64. Fronds slender, much contracted at the joints, 



but without diaphragms, tetraspores tripartite 



in depressed cavities Lomentaria 



Fronds slender, nodose, with diaphragms at the 

 nodes, tetraspores tripartite in the cortical 

 layer Champia 



Fronds contracted at the joints, but without 

 diaphragms, tetraspores tripartite in the corti- 

 cal layer Cliylocladia 



65. Fronds formed of a single row of cells (monosi- 



phonous) without proper cortex 66 



Fronds with distinct axial and cortical layers ... 75 



66. Fronds monosiphonous throughout 67 



Fronds composed below of a single row of 



cells, becoming densely cellular above, spores 

 formed by the division of any of the cells, fila- 

 mentous simple, gelatinous, dark purple Bangia 



