280 



Puget Sound Marine Sta. Pub. 



Vol. 1. No. 25 



p. 426, says the stipe of Alaria cordata is fifteen em. long. These varia- 

 tions show that the plants vary under different conditions and in different 

 localities. These variations must first be determined before definite lim- 

 itations can be set for the different species. 



33. PTERYGOPHORA Ruprecht 



1. Pterygophora californica Rupr. Algenstamme, p. 64. Fig. 45 



Holdfast composed of stout dichotomously branching hapteres ; stipe 

 erect, stout, two to seven cm. in diameter, solid, "woody," showing rings 

 in cross section, without mucilage ducts ; blades smooth and leathery, one 

 terminal and three or more pairs lateral ; terminal blade with mucilage 

 ducts and midrib-like thickening; lateral blades or sporophylls without 

 midrib ; sori on lateral blades, rarely on terminal blade, forming irregular 

 patches on both surfaces. 



Pterygophora californica 



Dilophus flabellatus 



PLATE 65 



Fig. 45. a. Cross section of solid "woody" stipe showing rings; 

 X 0.25. b, Sketch of plant; X about 0.03. 



Fig. 46. Sketch of plant. X 0.33. Drawn from Collins (1), 

 P. B. A., No. 843. 



