Ecklonia stolonifera Okam. 



Norrii Jam. : Tmru-arauu. 

 PL. CXL. 



Ecklonia stolonifera Okam. In the Marine Algae of Chosen (Report o 

 Imp. Bureau of Fisheries, Scientific Investigations, Vol. II, 1913; 



P2:85 = -iiir, i-/ M/g^^mmm) p. -<>, PL. vi. 



The fronds are broadly linear or lanceolate, 50-83 x 1 5-30 

 cm. simple or simple-pinnately branched, densely rugulose, roughly 

 toothed at margins, cuneate or roundish- ovate at base. The stem 

 is cylindrical, 13-23 cm. long, 3-5 mm. in diameter, solid, furnished 

 with more or less irregularly set double rows of mucilaginous 

 lacunae. The root fibres are verticillately arising, some of which 

 elongate into stolon, at whose apex a young leaflet is formed and 

 grows up into a new frond. The primary frond decays down 

 during autumn more or less toward the base of lamina, where a 

 new lamina grows up during the winter, which takes the place of 

 the lamina of the preceeding year after the manner of Laminaria 

 saccharina or L. Clousfoni. From the existence of double modes 

 of the vegetative reproduction, the formation of zoosporangial sori 

 seems to be suppressed. 



In the cross-section of stem a ring of mucilaginous lacunae is 

 seen half-way between the cortical portion and medullary layer 

 and another ring of smaller and more irregularly scattered lacunae 

 is situated just beneath the epidermal layer. Besides these two 

 rings, there is often present a portion of another ring near the 

 medullary layer. In lamina a layer of small roundish lacunae is 

 situated near the epidermal layer of both surfaces and the thickness 

 of the medullary layer is just the same as the breadth of cortical 



