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Chantransia trifila : A New Marine Alga. 

 By T. H. Buffham, A.L.S. 



(Read Feb. 19, JS92.J 



Plate III. 



The genus Chantransia includes some species which li-ve only 

 in fresh water, while others are found in the sea. Those 

 marine species known in Harvey's time as British were in the 

 Phycologia Britamiica included by him in Gallithamnion as he 

 considered they bore tetraspores. This, however, is now 

 known to have been a mistaken observation, as their neutral 

 organs are undivided, i.e., they are monospores. Until recently 

 the antheridia and cystocarps were known in only two species, 

 one fresh water : Ch. investiens Lenorm. ; the other marine : 

 Ch. corymhifera Thur. Mr. G. Murray, F.L.S., and Miss Ethel 

 S. Barton have, however, described and figured all three kinds 

 of reproductive organs in a new British fresh watei' species — 

 Gh. Boweri discovered by Mr. Murray and Prof. Bower in Scot- 

 land in April, 1890. For a full account of this species and of 

 the present position of this genus, which has had a remarkable 

 history, the student should refer to the paper by the authors 

 just named (" On the Structure and Systematic Position of 

 Chantransia'' in Jour. Linnean Soc, Vol. xxviii, p. 209). I 

 need only remind you that all the marine species are epiphytic 

 minute, generally even microscopic ; while the sexual organs 

 are of the simplest character known in the Florideoi. 



The plant I have to describe was found (Aug. 1890) epiphy- 

 tic on an old j)iece of Gladophora (? utriculosa Kiitz.) which, 

 fortunately for the study of the Ghantra7isia, had discharged 

 nearly all its green contents in the form of zoospores. As 

 there were several hundreds of specimens of the Chantransia 

 there was ample material for learning the true characters of 

 the epiphyte in all stages of the neutral or monosporiferous 

 state, there being no sexual organs found. 



