322 SUMMARY OF CUKEENT KESEARCHES RELATING TO 



is a reduction-division. All individuals are therefore alike, monoecious 

 haploid sexual plants with monosporangia. Tetraspores are entirely want- 

 ing. Carpospores of this stage are haploid. Floridege of this type are 

 here called haplobiontic Florideas (Scinaia, NemaUon ?), in contradis- 

 tinction to the diplobiontic Florideai {Folyslphonki, Griffifhsia, Delesseria, 

 Nitophyllum, Rhodoniela), which have haploid sexual individuals and 

 diploid tetrasporic ones. The carpospores in this stage are diploid. 

 The author gives his reasons for considering the haplobiontic type as 

 older than the diplobiontic. 



Oceanic Algology.* — A. Mazza, continuing his study of the family 

 DumontiaceaB, describes the structure and morphology of the following 

 genera : — Weekxia (2 species), DiJsea (2), Constantinea (3) ; and, passing 

 on to the Xemastomaceas, describes Caloslphonia (2 species), Flatoma (3), 

 Schizymenia (4). In addition to the account of the vegetative structure 

 of the holdfast, stipes, frond, prolifications, &c., notes on the 

 reproductive organs are given. 



Marine Algae of the Caroline and Marianne Islands. f — 

 K. Okamura publishes a list of species from these islands, consisting of 

 28 species of Chlorophycefe, 11 Phaeophyceje, and 22 Rhodophycefe ; 

 among which are 3 new species, DUophiis repens, HaJiseris repens, and 

 Halarachnion calcareum. The latter is the only species of the genus 

 known to be impregnated with lime in the inner tissue of the frond. 

 The geographical distribution shows that a great resemblance exists 

 between the marine flora of the Caroline Islands and that of the Indian 

 Ocean and the Malay Archipelago, as well as that of Ryukyu. 



Marine Algae of Chosen. :j: — K. Okamura publishes a list of the 

 marine algae of Chosen, in which he records 102 species, including a 

 new species of EckJonia, E. stolonifera. When the plant is quite simple 

 it is difficult to distinguish from Laminaria but for the marginal teeth 

 which are characteristic of EckJonia. Later it develops the usual lateral 

 branches or lobes and net-like rugosities. The primary frond decays 

 down during the autumn, more or less toward the base of the lamina ; 

 and a new lamina grows up during the winter replacing that of the 

 previous year, in the manner of Laminaria Cloustoni. The author 

 discusses the variety of temperature along the coast, due to cold and 

 warm currents, and its effect on the distribution of the algte. 



* La Nuova Notarisia, xxvii. (1916) pp. 1-53. 



t Bot. Mag. Tokyo, XXX. (1915) pp. 1-14 (1 pi.). 



X Rep. Imp. Bureau Fisheries, Tokyo, Sci. luvest., ii. (1913) pp. 17-80 (1 pi.). 



