380 PERCY SLADEN TRUST EXPEDITION. 
arrangement of the ramenta along the stem. Through a lens they sometimes appear to 
be distichous, as if forming single rows on the two opposite sides of the stem or 
branch (fig. 11), but a more careful examination shows that they form in reality two 
rows of alternating ramuli, instead of a single one, on each side. The ramenta emerge 
each singly from the stem, and do not bifurcate at the base as in Bryopsis gemellipara, 
Besides this simple arrangement of two double rows of ramenta, there are occasionally 
either one or two single or double rows of ramenta arising in the intermediate space 
between the original rows; and such plants have the appearance of bearing ramenta all 
round the stem until microscopically examined. This distribution of the ramenta is 
easily seen by a study of the scars left on the bare stem by the fallen ramenta. 
This mode of ramification separates our plant from the truly distichous group repre- 
sented by B. plumosa and also from the group including B. hypnoides, in which the 
ramenta arise all round the stem. 
The nearest ally to our plant is B. australis, which bears two double or triple rows of 
alternating ramenta. The difference between B. australis and our plant is found in the 
habit—B. australis having long bare branched stems, with short plumes at the top, 
3-5 mm. long; while in B. éndica the stems are much shorter and the plumes extend 
twice as far downwards from the apex (about 10 mm.) as in B. australis. In the latter 
species the ramenta, in fact, appear to be much more deciduous. 
B. australis was discovered by Preiss in West Australia, and, so far as we know, has 
never been recorded since. Authentic specimens are preserved in the Herbaria of the 
British Museum and Kew, which witness to the truthfulness of Kiitzing’s plate (Tab. 
Phye. vi. tab. 81, i.) so far as concerns the general habit of the plant. The Kew 
specimen, for instance, consists of some half-dozen long bare stems, arising from a 
fragment of main stem and having at their base the clasping rhizoids so often present 
in Bryopsis. At the summit of each branch is a short lanceolate plume of unbranched 
ramenta, which were described by Sonder in Lehmann’s ‘ Plantz Preissiane,’ ii. (1846-7) 
p- 152, as arising in a subhexastichous order. It is strange that J. G. Agardh, in 
his ‘Till Alg. Syst.’ viii. (1887) p. 27, states that he has not observed this mode 
of arrangement, and describes the ramenta as ‘ quoquoversum egredientibus,” 
without further detail. Kiitzing (loc. cit.) is unsuccessful in portraying the terminal 
plume and the arrangement of the ramenta. ‘hese latter are far too few in the 
figure, and are represented as emerging all round the stem, as indicated by the scars 
below. 
While examining other species of Bryopsis in the Herbaria of the British Museum 
and Kew, we have been able to identify several as B. indica, and thus add to the 
area of its distribution. Among these is Harvey’s unnamed specimen issued in his 
‘ Exsiccatee’ as Bryopsis sp., Ceylon, no. 99. Col. N. Pike also collected this species in 
Mauritius. 
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