I 1 [ 



described had been collected by Hombron off Java, and since that time they had never been 

 recorded in any later collection of marine algae, until our note and figures were published in 

 the Journal of Botany (1. c). 



Montagne (1. c.) described and figured Rliipidosiphou as a fan-shaped thallus composed 

 of dichotomous and anastomosing filaments ; and though in the Siboga collection we found 

 several plants e.xactly like Montagne's figure in size and habit, we were unable to detect in 

 any of them the characteristic anastomosis insisted upon by Montagne. So striking however 

 was the resemblance, that it inevitably suggested the possibility that Montagne had made some 

 error in his observation. And so indeed it proved ; for we discovered at last in one of our 

 plants some instances of "anastomosis", or rather of pseudo-anastomosis. In other words, the 

 so-called anastomosis observed by Montagne was an anastomosis, not of the filaments of the 

 flabellum, but of the lines of calcareous cement which fills the grooves between contiguous 

 filaments and also forms a connecting ring round the constriction at the base of each supra- 

 dichotomial branch. Montagne in fact mistook the opaque lines of cement for filaments, as 

 we endeavoured to shew by figures in Journal of Botany (loc. cit.). Finally, Montagne's type 

 in Herb. Mus. Paris is identical with the Siboga specimens and has no anastomosing 

 filaments. Another synonym is U. glaucescens var. temiis (or tenuior) Grunow in Ferguson's 

 Ceylon Algae (n° 439). 



U.javensis is the simplest form of Udotea, being characterised by a permanently mono- 

 siphonous stipes, simple, uncorticated and translucent, and by its small monostromatic flabellum 

 of filaments destitute of all lateral appendages. 



lts nearest allies are U. papillosa and U. glaucescens. From U. papillosa, which it 

 closely resembles in size, it differs in being entirely destitute of papillae on the filaments of 

 the frond. From U. glaucescens it differs in having a permanently monosiphonous stipes. In 

 U . glaucescens the stipes is monosiphonous m young plants only, and later becomes compound 

 and clothed with a cortex, produced by a multitude of lateral branchlets. Curiously enough 

 there is in the Siboga collection from Noimini Bay, Timor, a composite specimen which 

 in its frond exhibits filaments of U. papillosa chiefly, with a few filaments of U. javensis 

 intercalated side by side. 



U. javensis occurs in the Indian Ocean and on the shores of Japan. 



2. Udotea papillosa n. sp. 



Hab. INDIC. Siboga Expedilion. Stat. 296. Bay of Noimini, Timor reef! — Stat. 16. Kangeang 

 Island, reef! — Stat. 322. Sankapura roads, Bawean, reef! 



Plant usually small, reaching a height of about 2 cm. Stipes (or primary filament), when 

 young, simple, erect, monosiphonous, papillate above, not calcified, 70 — 100 p. in diameter; in 

 plants exceeding 1 cm. in height, this primary stipes becomes more or less concealed by a 

 covering of descendins? rhizoids issuino- from it at different levels. 



Frond thickly calcified, usually about 1 cm. long, and 0.5 — 1.0 cm. wide (4.5 cm. long and 

 2 cm. wide in subsp. suöpapillata), cuneato-flabelliform, monostromatic, striate, not zoned in 

 type, often deeply lacerate, here and there proliferous. 



