Page:Journal of botany, British and foreign, Volume 34 (1896).djvu/199

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177 A NEW SPECIES OF CAULERPA. By George Murray, F.R.S.Ed. Among the numerous interesting seaweeds collected by Mr. H. G. Flanagan, and sent to Miss Barton, there has occurred a very pretty Caulerpa of simple structure, which I find to be new. I have named it with much pleasure after Miss Barton, who has done so much to advance our knowledge of the seaweeds of South Africa. Caulerpa Bartoniae, sp. n. Frondibus a surculo repente glabro ramoso erectis, nudis (ramentis nullis) complanatis, ligu- latis, 2-4 centim. longis, 1-1|- millim. latis, supra petiolum brevem identidem dichotomis, interdum fastigiatis, parce constrictis, mar- gine integro, apice obtuso ; rhizinis brevibus, tenerrimis. Hab. In rupibus submersis ad oras Africae austr. (Kaffraria Brit.). The species falls into the section ZosteroidecB of Agardh's classifi- cation of Caulerpa, and particularly near C. ligulata, from which it differs mainly in the very frequently repeated dichotomous branching of the fronds, the absence of a rugulose petiole, so characteristic of C. ligulata, and of course very greatly in stature. In many ways there is a resemblance to C. Freycinetli (sect. ThuyoidecB), but the fronds do not possess the beautiful regular dentate margin of this species, nor the regular strongly-marked petiole. C. BartonicB is a much smaller and slighter species altogether. Zanardini (Plant, in mari rubro, &c., in Mem. dell. Istituto Veneto. vii. 1857, p. 283, tab. xiv. fig. 2) has described and figured a var. integernma of C. Freycinetli with an entire margin. The figure, however, is of a much larger plant with yellow-tipped fronds, and in fact very little indication that it is a Caulerpa at all. Moreover, its occurrence at Suez scarcely encourages one to regard this variety as identical with the well-marked species I now describe. I may say that if Zanardini's plant be a Caulerpa, it is exceedingly unlikely to be a variety of C. Freycinetii, which displays with un- varying constancy the same characters whether it occurs in the Journal of Botany. — Vol. 34. [April, 1896.] n