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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. Ilarriman Exp., 1901, p. 429, pi. 51 ; Setchell and Gardner, Alg.
X.W. Amer., 1903, p. 262; Setchell, Post-emb. Stages, 1905, pp. 119-
12::. pi. 12, Kelps of the U. S. and Alaska, 1912a, p. 152. Latjiinaria
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.
Hedophyllwm sessile is the type of the genus. It is the Laminaria
sessilis of Agardh {lor. 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 (lac. 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
;