370 
only to the Pacific from the Indian Ocean, another only to the Atlantic 
from the Indian Ocean. The Cymodocea, though present in Africa, 
appeal’s not to be recorded from the Mascareue Islands, and Sargassuvi 
ilicifolium though occurring in Malayan Avaters, has not yet been found 
on the coasts of Northern Australia. One species, Dictyota dichotoma, 
is rather more frequent in sub-tropical than in tropical seas and is 
cosmopolitan in both the northern and the southern hemispheres. 
The next group of species to be considered—the “ littoral ”—in¬ 
cludes many plants for which the evidence of introduction by the sea is 
almost as palpable as in the case of the “ marine ” species themselves. 
They gei-minate on the beaches, and grow only near the sea, preferably 
in muddy creeks or on the sand or shingle ; their fruits and seeds are 
found in every “ drift ” and the species themselves occur on every Indian 
or Malayan coast. Such are the true mangroves and the species like 
Avicennia, AEgiceras, Garapa, that are constantly associated with the 
mangi’ove-vegetatiou ; the sand-binding species like Ipomoea biloba, 
Euphorbia Atoto, Sesxivimn Portulacastrum, Vigiia lutea, Thuarea sar- 
mentosa ; the tropical sesb-lence oi Pandanits odoratissimus, Desmodium 
^imhellatum, Sophora tomentosa, Tournefortia argentea, Glerodendron 
inerme, Vitex Negundo, with its concomitant climbing vegetation, Cana- 
valia obtnsifoUa, Ipoyncea digitata, Argyreia tilicefolia; the outer beach- 
forest of Terminalia Gatappa, Hernandia peltata, Erythrina indica, 
Stephegyne diversifoUa ; the inner beach forest of Cycas, Mimusops and 
Pisonia; and even the species of the mud-flats within, like Leea mm- 
bucina, Hibiscus tiliaceus, Cynometra ramiflora, Flagellaria indica and 
many more. The seeds of all these have been observed by the writer 
in the “ drifts ” of these islands and many of them have been noted, either 
in the Andamans and Nicobars, or in Narcondam, germinating on the 
beach. There are others, however, that are more doubtful, and, though 
the whole of the species for which this mode of introduction is con¬ 
ceivable are given below, the species for which any doubt is possible are 
enclosed in brackets and the more equivocal of these are discussed at 
the end of the list.* 
* Since this paper was written and while these pages have been passing through 
the press two papers have appeared that deal with this section of the flora of the 
Malayan countries much more fully than the scope of the present paper permits. 
To these papers, viz :—Schimper : Die Indo-Malayische Strandflora (Jena ; Gustav 
Fischer, 1891) and Karsten : TJeher die Mangrove-Vegetation in Malayischen Archipel ; 
Bibliotheca Botanica, Heft 22 (Cassel: Theodor Fischer, 1891) neither of which had 
appeared when the writer’s remarks were written and which he greatly regrets having 
been unable to refer to in the text, the writer would refer those who are interested 
in the subject of mangrove and coast plants and the influence of ocean-currents and 
their distribution. 
189 
