ON THE liAMIN AK1ACEAE OF HOKKAIDO 
7 
September on, forming sori on the upper, rarely also on the under 
surface 7 ^ of the blade ; sori extending from the lower portion of 
the median fascia upwards, covering nearly its whole surface within 
a region corresponding to 1/4— 1/3 of the overall length of the blade, 
becoming discontinuous and finally disappearing in areas above that 
region. 
Mucilage canals in the stipe arranged closely in a row in outer 
cortex, sometimes in two rows as in a compressed stipe of a specimen 
from Yamakoshi; medulla of the blade rather thin, composed of 
filamentous cells running generally lengthwise ; mucilage canals in 
a mature blade arranged in two rows in the median fascia (Plate 
29, fig. 1), but in one row in the marginal portion. Zoosporangia 
clavate, with a slight thickening of the membrane at the apex, 
100-112.5 fi long, 11.8-13.2 // broad at the broadest portion ; para- 
physes filiform, 163.3-174.2 n long, 5.9-6. 6 u broad, capped with a 
marked gelatinous thickening of the membrane, 28.3-40.2/7 thick. 
Habitat. Growing in clear sea-water along the coasts facing 
bays and exposed to not very rapid tidal movements, washed by 
a warm current mingled with a faint distal reach of a cold current, 
on rocks lying from the maximum low water mark downwards, 
most abundantly in the depths between 4-5 fathoms and 7-8 fathoms, 
rarely in the depths of 24-25 fathoms in some localities. Distri- 
buted in Hokkaido along the coast from Muroran southwestwards 
as far as Kikonai of Kami-iso Gun. The dried fronds of Laminaria 
produced from the vicinity of Osatsube Village in Kayabe Gun are 
known to be of the best quality. Those produced from the vicinity 
of Shiokubi, Kameda Gun, were once highly estimated in the market 
being called “Shinori-kombu.” However, they are of thinner sub- 
stance and somewhat inferior quality as compared with those from 
Osatsube. The specimens from Muroran, Yamakoshinai, and Kiko- 
nai are often found to have a flattened stipe. The dried fronds 
of Laminaria produced from Mimmaya in Aomori Prefecture belong 
to the present species and bear a close resemblance to “Shinori- 
kombu” in its quality. 
Use. The present species is most rich in the sugar content 
among our Laminarias, and is used for giving flavor to food and 
for manufacturing sweets. 
7) See foot-note no. 6 on page 5. 
