NO. 8 DAWSON : A REVIEW OF THE GENUS RHODYMENIA 127 



Blades mostly as broad at apex or broader than be- 

 low ; type : — Australia R. foliifera 



Blades attenuated toward apex; type: — New Zea- 

 land R. novazelandica 



IV. Tetraspores in rounded sori as in Sec. Palmettae; cortical layers 

 modified in tetrasporic areas to give a more or less nemathecioid 

 structure ; some modification is present, though it may be obscure 



Sec. 4. CLINOPHORA 



Stipes prominent, long 



Tetraspores in sori below apices of fronds; type: — "in 



mari australi" R. linearis 



Tetraspores largely covering lobulate proliferations of 

 the upper frond-segments ; type : — California .... 



. . . R. lobulifera 



Stipes neither long nor absent 



Habit erect; segments narrow, little branched, not 

 spreading; type: — Australia . . . . R. stenoglossa 

 Habit spreading; branches variously dichotomous 



Branches adhering to each other at places of contact 

 by rootlike disks or by fusion ; type : — Japan . . . 



R. intricata 



Branches not adhering or fusing 



Foliations, when present, submarginal, often al- 

 most superficial ; type : — So. Africa R. capensis 

 Foliations, when present, marginal 

 Segments with blunt apices 



Frond-apices proliferating again and 

 again; type: — Tasmania R. prolificans 

 Frond-apices nonproliferous 



Segments 2-3 cm. broad ; base of blade 

 broad, cuneate; type: — Falkland Isl. 



R. Schmittii 



Segments usually less than 1 cm. 

 broad; base of blade narrow; type: — 

 East Indies . . . . R. australis 

 Segments narrowed at apices and acute ex- 

 cept in cases of lobing of tetrasporic blades; 

 type: — California . . . . R. attenuata 



