NO. 8 DAWSON : A REVIEW OF THE GENUS RHODYMENIA 145 



turn basium laminarum amplexicaulibus; segmentis patentibus, flabella lata for- 

 mantibus, apicibus rotundatis, 4-5 mm. latis; tetrasporangiis cystocarpiisque 

 nondum visis. 



Frond 7 cm. high from a simple discoid holdfast above which branched 

 stolons grow down to form a loose tangle around the base of the stipe; 

 blades irregularly dichotomo-flabellate, terminating each joint of the 

 sympodially branched stipe which arises by branching successively from 

 the surface of the base of each previously developed blade, forming by 

 continued growth an amplexicaul structure in the region of each branch 

 (figs. 21-23) ; segments spreading almost at right angles to the stipe, 

 forming a broad flabellum; apices rounded, 4-5 mm. broad. Tetraspores 

 and cystocarps unknown. 



Type. — Chile, Prov. Concepcion, west shore of Concepcion Bay; 10 

 km. north of Talcahuana; rocks at upper low tide level, Jan. 4, 1936, 

 James West 5078d of Univ. of Calif. Bot. Gard. Exped. to the Andes, 

 1935-1936; Herb. Univ. Calif. 543963. This specimen is apparently 

 identical with Skottsberg's less mature specimens from Valparaiso (St. 

 41,2.9.08). 



It was the best of good fortune that the specimen collected by James 

 West in Chile was available in the Herbarium of the University of Cali- 

 fornia. Without this specimen the confusion which has long surrounded 

 Rhodymenia flabellifolia would undoubtedly have continued. Skottsberg 

 in 1923, working on the Patagonian Rhodophyceae, attempted to clarify 

 the situation, but the material he used for comparison was very young, 

 and his specimens were referred to R. flabellifolia (Bory) Mont. His 

 synonymy is correct in that Howe's specimen, named R. flabellifolia 

 (Mar. Alg. Peru (1914) ), is of the same species as Bory's type, since it 

 corresponds in all essentials with Bory's figure. Careful comparison of 

 West's specimen with Skottsberg's figures shows that it is identical with 

 the material of Skottsberg's own collection which he illustrated as Den- 

 drymenia flabellifolia, but is quite a different plant from the species as 

 re-established by Howe. Close relationship in several morphological 

 characters is to be found between R. Skottsbergii and R. flabellifolia 

 (Plate 21), but the former differs very strikingly in the amplexicauline 

 development of the bases of the blades around each successive branch of 

 the stipe. In R. flabellifolia there is frequently a decurrent growth of stipe 

 and blade at their points of junction but never the amplexicaul character. 

 The specimen at hand has a more coriacious texture to the frond as well. 

 Reproductive bodies are unfortunately absent, but the external mor- 



