XII. On a new Specjes-of Rhipilia (В. Andersonii) from Mergui Archipelago. By 
GEORGE Murray, F.L.S., Assistant, British Museum (Natural History), and 
Lecturer on Botany, St. George’s Hospital Medical School. 
(Plate ХХХТ.) 
Read March 4th, 1886. 
THE Вира which is the subject of this paper was collected by Dr. John 
Anderson in the Mergui Archipelago in February 1882, and presented to the British 
Museum in January of this year; it was found growing on mudflats at low water 
(spring tides) in King’s Island Bay. The genus Rhipilia was established by Kützing 
(‘Tabulz Phycologice,’ Bd. viii. 1858) for the reception of two species (В. tomentosa, 
Kütz. and R. longicaulis, Киа.) collected by Sonder in the Antilles. To these the 
late Professor Dickie added a third species, В. Rawsoni, from Barbadoes (Linn. 
Soc. Journ., Bot. vol. xiv. p. 151), of which the type specimens are now in the 
British Museum. Professor Dickie had, about this time, intended to add another 
species from Mauritius (collected by Colonel Pike) under the name of В. polydactyla: 
and the plant is so labelled by him in the Kew Herbarium. On referring, however, 
to Dickie’s own Herbarium in the British Museum, it was seen that % R. polydactyla, 
n.s.,” had been cancelled by him and the alga placed under its true name, Spongo- 
cladia vaucherieformis, Aresch., and so published in Linn. Soc. Journ., Bot. vol. xiv. 
р- 199. 
To these three species I now propose to add a fourth, bearing the name of Dr. 
Anderson, who found it. 
RHIPILIA ANDERSONII, n. sp.: sessilis, integro-flabelliformis, interdum paulisper lace- 
rata; textura coacta, tomentosa; ccelomata regulariter dichotoma, inferne fulva, 
sursum fulvo-aurantiaca, irregulariter et longis intervallis constricta, apicibus 
obtusis subclavatis ; rhizinze inzequaliter torulosz. 
This species differs from R. longicaulis and В. tomentosa in the frond being completely 
sessile on the mass of rhizoids, and from В. Rawsoni, which has a much lobed sessile 
frond, in having an entire one. It agrees with R. Rawsoni in having obtuse subcla- 
vate apices to the frond-filaments, though in В. Rawsoni these are torulose throughout 
their length. А. longicaulis has hair-like points to its torulose filaments, and 2. tomen- 
(ова has irregularly branching filaments with dilated apices. All the species have 
regularly dichotomous branches, except В. tomentosa, which Kützing describes as 
*jrregulariter ramosissima, subdichotoma.”  Kützing founded the genus on two 
stipitate forms, while both Professor Dickie's В. Вашзот and the present one are 
sessile. 
SECOND SERIES.—BOTANY, VOL. II. 2M 
