ON THE KAMIN A III ACE AE OF HOKKAIDO 
31 
Holdfast composed of filiform hapteres arising verticillately, 
branching several times. Stipe circular or elliptical in cross section 
at the lower portion, somewhat compressed upward, variable in 
length, from only 2.3 cm up to more than 15 cm ; a short-stiped 
individual, in general, bears a broad blade and a long-stiped one 
a narrow blade. Blade variable in shape too, elliptical or linear 
oblanceolate, or linear, broad in individuals growing in mild tide, 
but narrow in those growing in rapid tide, in shorter individuals 
up to 33-66 cm in length, but in longer individuals up to 2-3 m 
or more. Reproductive organs maturing in summer season, from 
June to September. 
Habitat and use. Ubiquitous in Hokkaido. Very widely dis- 
tributed in the North Pacific, being distributed on the one hand 
southward as far as Mutsu and Rikuchü in the main island of 
Japan, and on the other northward from the Kurile Islands as far 
as the northwest coast of North America. This kelp grows in 
company with Laminaria spp., and so it often becomes one of the 
competitors of the latter, proving a hindrance to their propagation. 
Juvenile individuals are sometimes utilized as food by people. 
Addenda. In 1819, Turner first published an illustration of the 
present alga based on specimens from the western coast of North 
America and named it Fucus costatus. Grevit/le, in 1824, established 
the genus Costaria for the species concerned, and changed its name 
to Costaria Turneri. This name is still generally accepted as valid 
today/' 0 In 1857, the government of the United States despatched 
Admiral Rodgers to engage in an exploratory expedition to the 
northern part of the Pacific Ocean. The specimens of marine algae 
brought back by this expedition were sent to Harvey for identi- 
fication. Among them were some specimens of Costaria Turneri 
collected at Hakodate Harbor. According to Harvey’s description, 
they differ from the American plant in having four ribs instead 
of five and small perforations on the blade, and are therefore to 
be treated as var. pertusa. However, the author has never met 
with an individual bearing a four-ribbed blade among the specimens 
examined. Harvey’s specimens might have been malformed in- 
dividuals. To make special mention of the perforations which 
31) Setchell and Gardner (1925, pp. 610 611) adopted Costaria costata (Turn.) 
Saunders in place of Costaria, Turneri Grev., and since then that name has generally 
been used in the leterature. 
