Japanese Botanical Work

Abstract

THE Journal of the CollegeS of Science of. the Imperial University of Tokyo, vol. xliii., contains (article 1) an admirably illustrated monograph (in. English) of the genus of brown seaweeds, Alaria, by Prof. K. Yendo. The author has studied the various species on the west coast of Vancouver Island, along the coast of the Kurile Islands and of Kamtschatka as well as in Japan, and also the material in some of the important European herbaria. The descriptive portion is preceded by a general account of the morphology, structure, and development. The vexed question of the cryptostomata in the brown seaweeds is discussed at some length, and the author concludes that these tufts of hairs, at any rate in the Laminarias, may be regarded as absorptive organs. A r ©sum © is also given of the differing views held as to the life-history, especially as to evi4enoe on the manner of renewal of. the blades, of Alaria, which, the author considers, “may be either gradual or sudden, according to the conditions of the place where the plant grows.” As regards the economic uses of Alaria, though A. esculenta was extensively, used for food in earlier times in North-West EuroDe, and this and other species are still eaten in various sub-Arctic areas, the author concludes that the genus has very little value as human food or for kelp-ash. For manure it may be used equally well with other brown seaweeds. The species inhabit the colder northern seas, the greatest number being found within a range from about 42° N. up to the Arctic Circle. Fifteen species are recognised. Of these full descriptions are given, variations in form and synonymy are discussed, and a list of localities is cited. The form and structure of the species are illustrated in nineteen excellent double-page plates.