HOW TO KNOW THE SEAWEEDS 



165a Terminal portions of fertile dichotomies swollen and broader than 

 region below. Fig. 208 166 



Figure 208 



Fig, 208. Pelvetiopsis limitata (Setchell) Gardner 



Habit of part of a plant, X 0.7, showing the swollen ends of the 

 branches (receptacles) containing the small, simken, fertile cavities 

 (conceptacles). This is a common species of middle and high inter- 

 tidal rocks from central CaHfornia northward. 



Pelvetia fastigiata (J. Agardh) De Toni, which is similar in habit 

 and habitat, but much taller, occurs commonly along the entire Cali- 

 fornia coast to southern Oregon. In southern California it is the only 

 such olive-green, ribless species with swollen branch apices on the 

 high intertidal rocks. 



165b Terminal portions of fertile dichotomies about the same width as 

 lower parts, or, if broader, at least not swollen 167 



166a Thalli short, 4-15 cm. tall; macrosporangia (oogonia) with only 

 one fimctional spore. (See Figs. 208, 209A). . .Pelvetiopsis limitata 



158 



