618 University of California Publications in Botany [Vol. 8 



Setchell, in Collins, Holden and Setchell, Phyc. Bor.-Amer. 

 (Exsicc), no. VIII, Notes on Algae, I, Zoe, 1901, p. 121; Saunders, 

 Alg. Harriman Exp., 1901, p. 429, pi. 51 ; Setchell and Gardner, Alg. 

 N.W. Amer., 1903, p. 262 ; Setchell, Post-emb. Stages, 1905, pp. 119- 

 123, pi. 12, Kelps of the U. S. and Alaska, 1912a, p. 152. Laminaria 

 sessilis Agardh, Syst. Alg., 1824, p. 270; Tilden, Amer. Alg. (Exsicc), 

 no. 344. Laminaria apoda Harvey, Notice of a collection of algae, 1862, 

 p. 167. 



Hedophyllum sessile is the type of the genus. It is the Laminaria 

 sessilis of Agardh (lo'C. cit.), said to have come from "Mari Australi. " 

 The type specimen of L. sessilis is in the herbarium of J. G. Agardh 

 under number 1730. Also in the same herbarium under number 1731 

 is a plant marked "Laminaria apoda Harv., Esquimalt. " This was 

 probably contributed by Harvey, 



Both of these specimens have been carefully examined by one of 

 us (Setchell) and found to be our plant, H. sessile. It was next col- 

 lected by Dr. David Lyall in the "Fuca Straits" and later classified 

 as Laminaria apoda by Harvey {loc. cit.). There are six specimens 

 in the herbarium of Harvey at Dublin, probably of this collection, 

 which have been examined by one of us (Setchell) and found to be 

 good H. sessile. 



The size of the plant and the amount of bullations depend largely 

 upon the habitat in which they grow. On exposed coasts, e.g., at 

 Fort Ross, California, they are short, scarcely over three decimeters 

 long and practically the whole blade is much bullated. At Neah Bay, 

 Washington, in a sheltered location, where they grow in great pro- 

 fusion at and below extreme low water level, the blade frequently 

 becomes fifteen decimeters long and eight decimeters wide, folding 

 back and forth as it widens and becoming attached at the base. The 

 blades may be entirely smooth or only the lower parts bullate. 



2. Hedophyllum subsessile (Aresch.) Setchell 



Young fronds provided with a normal holdfast, attached by a few 

 branched hapteres ; stipe short, stout, somewhat flattened ; blade of the 

 young plant at first narrow and simple, later becoming broader than 

 long and divided, with a cordate base and marginal rows of bullae ; 

 at maturity the base becomes deeply cordate or even reniform, the 

 basal margins are much thickened and give rise to hapteres which 

 attach the thickened bases to the substratum ; the central portion of 



