270 THE BOTANICAL MAGAZINE. . [Vol. xxix. No. 346. 



which, however, is not the ease in matured frond. Though the 

 wings of stem in Hirome remain in the most cases sterile, yet 

 cases are not rare where they become fertile and then the fertile 

 wings may safely be called sporophvlls, though they are less 

 significant than those of Undaria pinnatifida. Then, Hirome 

 has sporophyllic sori and at the same time laminal ones, both 

 in continuation, which become confluent covering the costal 

 area mostly at the basal portion of frond. Undaria pinnatifida 

 has also soriferous area, though in a less extent, at the base 

 of the lamina running continued from the sporophylls ; but in 

 it sori on both sides of the costa are always free from one an- 

 other. Thus, the difference between Hirome and Undaria now is 

 reduced, the remaining characters being common, to the broader 

 or narrower extent of the soriferous area of lamina, its spread- 

 ing or not spreading over costa and greater or less development 

 of the wings of stem into sporophylls. To retain a plant in a 

 different genus by such a few and relatively subordinate char- 

 acters seem to be incorrect. 



Secondly we will consider Laminaria Peterseniana. This 

 plant differs widety from Laminaria, amongst others in the 

 characters of paraphyses, in which mucilaginous mass is cap- 

 ping their apices, while in Laminaria it is present on all round. 

 The capping of paraphyses with mucilaginous mass in Alaria, 

 Undaria and Laminaria Peterseniana has for the first time been 

 noted by Prof. Miyabe. 1} Moreover this alga has mucilaginous 

 glands which are very characteristic to this plant and the 

 related species, and of the development of which Prof. Yendo 

 made a careful study. They have been noted at first by the 

 writer 2 -* in Laminaria Peterseniana and afterward by Prof. 

 Miyabe in U. pinnatifida and var. distans and lately by Prof. 

 Yendo 3) in Hirome. Thus, the presence of cryptostomata, of 

 the characteristic mucilaginous glands, and of paraphyses cap- 



1) Miyabe : Laminaria Industry. Eeport on Fisheries of Hokkaido, Vol. Ill, 

 1889, p. 8 in Japanese. (Vid. Yendo, Three ntw mar. alg. fr. Jap., PI. Ill f. 7-8.) 



2) Okam. : On Laminar of Jap. (Bot. Mag. Tokyo, 1896, Vol. X), p. 97, pi. VII, 

 f. 13-14. 



3) Yendo : Three new mar. alg. fr. Jap. p. 102, PI III, f. 6. 



