1 1 



obtained from deep water (23 fathoms). It is more than twice as large as the type, has a delicate 

 thin frond, and differs in having in its upper filaments (tig. 42) much less prominent papillae 

 which are more widely spaced out, and in having the base of the rlabellum beset with fibulae 

 (fig. 40). Possibly its differences are due to the depth at which it grew. At first sight it is 

 remarkably like U. glaucescens. Having only the one specimen and that from deep water only, 

 we hesitate at present to carry out our intention of publishing this plant as a new species under 

 the name - ■ Udotea subpapillata. We have however placed it as a species in the table 

 of affinities (p. 7). 



As mentioned under U. javensis^ we have found among the specimens from Noimini 

 Bay, Timor, a frond of U. papil Vosa containing a fortuitous intercalation of filaments of 

 U. javensis, growing amicably side by side. The geographical distribution, as at present 

 known, is confined to the Malay Archipelago, where it is found with U. javensis. 



3. Udotea glaucescens Harv. 



List of Friendly Islands Algae, n° 82 (nomen tantum). 

 Syn. Udotea glaucescens J. G. Agardh Till Alg. Syst. V. 1887. p. 70. 

 Udotea glaucescens De Toni Syll. Alg. vol. I. 1889. p. 505. 



Hab. INDIC. Cargados Carajos, 30 fathoms, J. Stanley Gardinerl — Sumatra, Wray, in Herb. Kew! 



Siboga Expedition. Lirung! with monosiphonous stipes. 



PACIFIC. In the lagoon, Tongatabu, Friendly Islands Algae, Harvey n" 82 ! - - Rawa, Feejee 

 Islands, 1850, Harvey in Herb. Kew! — Cape York, North Australia, " Challenger" Expe- 

 dition! — Torres Straits, "Challenger" Expedition! 



Plants varying in length to about 8 cm., encrusted with lime, radicelliferous below. 

 Stipes simple, sometimes once branched, sometimes sparingly divided at apex, up to 4 cm. 

 long, monosiphonous at first, subsequently becoming covered with descending branches and a 

 thick cortex of fibulae or lateral appendages. 



Frond from a cuneate or rounded base, flabellate, typically monostromatic (except 

 sometimes at base), sometimes consisting of two or more loosely superposed lamellae arising 

 from the inconspicuously divided top of the stipes, glaucescent, not zoned, not corticated. 



Main filaments of the frond more or less calcified, 65 — 105 a in diameter, radiating 

 from the stipes to the margin, parallel, dichotomously or rarely trichotomously branched, 

 unequally constricted above the dichotomies, laterally adherent, not flexuose. 



Filaments of stipes of mature plant bearing lateral appendages which terminate in short, 

 simple or lobed, truncate capitula, botryoidally arranged, and form an irregular cortex to the 

 stipes. [Figs. 3, 5, 7, 8, 43]. 



Udotea glaucescens Harvey existed first only as a herbarium-name to denote plants 

 found by Harvey in the Friendly Islands, and distributed as n" 82 in bis List of Friendly 

 Islands Algae (fig. 3). It was first described by Prof. J. G. Agardh (Till Alg. Syst. 1. c), who 

 likens the thallus to the frond of Rhipocephalus. Its chief characteristic is the monostromatic 

 frond composed of parallel, closely adherent filaments (fig. 5), which branch dichotomously 



SIBOGA EXPEDITIE LXLI. 15 



