90 



I find an annual ring corresponding to the growth of the former year. 

 The stem of the first year has a length of 22 — 27 cm with a diameter 

 of ca. 10 mm, while the dimensions of that of the second year are 40 — 50 

 cm by ca. 15 mm. 



Lamina is lanceolate rising from broadly ovate or slightly caneate 

 base with undulated margin. Median portion does not much differ in 

 thickness from the remaining. The shape of lamina does not vary accord- 

 ing to its ages, but the size is very different. The lamina of the first year 

 is 40 — 70 cm long and 15 — 20 cm broad, while that of the second year 

 is 170 — 220 cm by 30 — 40 cm. These measurements have been taken 

 from dried specimens the exact length being unknown, on account of 

 the loss of the terminal portion by erosion. In a cross-section of lamina 

 we find the intermediate layer consisting of several layers of roundish- 

 angular cells, whose diameter gradually diminishes towards the periphery. 

 Muciferous lacunas are present beneath the cortex a little to the outward 

 of half the thickness of the middle layer. 



Sori are produced on both surfaces, forming large and irregular 

 cloud-like patches which are equally spread all over the surface, leaving 

 a narrow intra marginal portion naked. They seem to be produced at first 

 in median portion and gradually to extend afterward toward the margin. 

 Sometimes they are formed far above the base of the frond or in others 

 in the basal portion. In several, specimens, however, the basal portion 

 is left naked for a more or less wider range. In marginal portion of 

 the frond sori are formed in roundish spot-like patches and those becoming 

 confluent with each other form larger patches. 



It seems rather peculiar that such a larger plant as the present 

 remained undescribed up to this day, in spite of earnest and diligent 

 searches of many eminent European botanists who took home huge mass 

 of collections from the Upper Northern Pacific. It is doubtful whether 

 the present plant has hitherto been not taken for Laminaria japonica or 

 L. saecharina, instead of being established as a distinct species. 



The present plant is closely related with Laminaria japonica Aresch. 

 from which however it differs in the length of stem, position of lacunas 

 in stem, and the indistinct median fascia. Moreover, L. japonica is an 

 annual plant, while the present is perennial, — or at least biennial. It 

 is difficult to distinguish the present species from L. japonica by the 

 structure of lamina, its cross-section being pretty much the same in both. 



