PLATE XX. 

 [Proc. Wash. Acad. Sci., Vol. Ill, PI. LIII.] 



FIG. i. Alaria lanceolata, Kjellm. ; ^ natural size. 



2. " " " section of blade, natural size. 



3, 4. " " " young plants. 



[468] (2 3 2) 



