126 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 3 



glyphic sori; margins entire; type: — East Indies . . . 



R. Setchellii 



Fronds expanded palmately or flabellately, not strictly di- 

 chotomous, sometimes various in R. palmata and R. palmati- 

 f or mis 



Frond-margins more or less undulate-crisped or folded 

 Frond-margins bearing spinules ; type : — Japan . . 



R. spinulosa 



Frond-margins entire 



Fronds broadly membranaceous, erect; type: — 



Japan R. punctata 



Fronds linear, irregularly lobed, crenulated, de- 

 cumbent; type: — Japan R. coacta 



Fronds plane throughout 



Blade in cross section showing a distinct line between 

 cortex and medulla; type: — Patagonia . . . . 



R. pabnatiformis 



Blade in cross section showing a more gradual change 

 in cell size from cortex to medulla; type: — Atlantic 

 coast of Europe R. palmata 



III. Tetraspores in rounded sori usually confined to frond-apices or 

 proliferations; cortical layer not distinctly modified by tetra- 

 spores Sec. 3. PALMETTAE 



Atlantic and Mediterranean species 

 Fronds dichotomo-flabellate 



Fronds with prominent stipe; type: — England . . 



R. palmetta 



Fronds largely sessile; type: — Mediterranean . . 



R. corallicola 



Fronds dichotomous but not flabellate, the segments 

 linear, not spreading; type: — Mediterranean R. ligulata 

 Eastern Pacific species 



Plants large, 10-25 cm. high; segments 3-6 mm. broad; 



type: — Peru R. Howeana 



Plants smaller, 4-12 cm. high; segments 2-3 mm. broad; 



type: — California R. calif ornica 



Western Pacific species 



Segments very narrow; type: — Japan . R. liniformis 

 Segments not strikingly narrow 



