190 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Growth of Crustaceous Algae.* —Madame Lemoine publishes a 

 preliminary paper on the growth of marine alsra? at Roscoff. She finds 

 that in crustaceous algae, Melobesieae, Ralfsiaceae, and Squamariaceae, 

 the rate of growth is much slower than in other algae. In general, it is 

 at the rate of less than 1 cm. a year and often only a few millimetres. 

 Most other marine algae, on the contrary, grow at least 1 cm. a month, 

 often 2-3 cm. The maximum observed was 5 cm. a month for certain 

 individuals of Fucus and Laminaria. The author gives details of her 

 experiments and tables of results, with a chart. She considers that two 

 factors influence rate of growth, viz. exterior conditions and substratum. 



Melobesiese of Ireland.f — Madame Lemoine reports on the species 

 of Melobesieae collected by A. D. Cotton at Clare Island and in the 

 neighbouring district. The number of species recorded is fifteen, one 

 of which is new to Ireland. Valuable critical notes are appended to 

 each record, treating of structure, distribution, etc. The author finds 

 that Lithophyllum agariciforme is merely a local form (L. lichenoides 

 Phil.), and that Epilithon corticiforme isa synonym for E. membranaceum. 

 Hitherto this latter species has always been found growing on other 

 algae.. In this collection it is growing on a shell of Trochus. The 

 paper closes with a comparison of the Melobesieae of the east and west 

 coasts of Ireland. 



Rhodophycese of the ' Sealark.'J — A. Weber van Bosse reports 

 on the Rhodophyceae collected during the ' Sealark ' Expedition by 

 Professor J. Stanley Gardiner in the Indian Ocean. A certain number 

 of novelties are described and figured. The critical notes appended to 

 many of the records give important details of structure. 



Sargassum.§ — F. Borgesen writes on the species of Sargassum, 

 found along the coasts of the Danish West Indies, four in number, and 

 the two floating Sargasso, found in the Sargasso sea, S. natans and S. 

 hystrix var. fiuitans, a new variety. He then discusses the biology, 

 affinities, and origin of the gulf -weed, reviewing previous work and 

 views on the subject. He proves very convincingly that the gulf-weed 

 is a true pelagic alga, that it is a perennial, and lives and dies at sea. 

 As to its origin, he presumes that it has most probably descended from 

 forms living on the shores of the West Indies and neighbouring coast 

 of America, and he discusses the points of similarity between it and 

 S. vulgare and S. Filipendula. He considers that the amount of organic 

 detritus produced by the pelagic Sargassum may be of great importance 

 to the economy of the sea, especially in the tropics where plankton is 

 not very rich. 



* Bull. Inst. Oceanograph. Monaco, No. 277 (1913) 19 pp. 



t Nouv. Arch. Mus Hist. Nat. Paris, ser. 5, v. (1913) pp. 121-45 (figs, in text). 

 % Trans. Linn. Soc. Bot., viii. (1913) pp. 105-42 (3 pis. and 1 fig. in text). 

 § Mindeskrift for Japetus Steenstrup. Copenhagen : 1914, No. xxxii., 20 pp. 

 (figs, in text). 



