HOW TO KNOW THE SEAWEEDS 



25b Thallus with more or less uniform, short, multifarious branchlets 

 borne on percurrent axes. Fig. 42 Heterochordaria abietina 



Fig. 42. Heterochordaria abietina 

 (Ruprecht) Setchell & Gardner 



Part of a group of erect axes, X 1. 

 A common species at middle tide 

 levels from central California north- 

 ward to Alaska. Plants reach 20-25 

 cm. in height. The axes and branch 

 es, which at first are solid, may later 

 become hollow but usually will not 

 give the impression of being hollow 

 unless sectioned. 



Figure 42 



45 



