382 
This list includes 94 species for which sea-introduction is conceivable, 
and for the presence of most of the species it contains this mode of intro¬ 
duction is almost certainly responsible. The list might even be made more 
extensive than it is, for if StercuUa ruhiginosa, which is a purely “ litto¬ 
ral ” species here as it is elsewhere throughout the Andaman and Nicobar 
groups—to which area the variety found in the Coco Islands is strictly 
confined,—be sea-introduced, there is no reason why some of the other 
species of Sterculia should not bo added. As a matter of fact the writer 
has collected specimens of species of StercuUa in Nai-condam and in Batti 
Malv, the first island a locality where certainly, the second one where 
probably, every species present has been somehow or other introduced. 
But no StercuUa seeds were recognised in the “ drifts ” and therefore 
the whole of the species have been left out except this purely ‘ littoral ’ 
one, while even it has been omitted from consideration in the analysis 
of the table which follows. Again, Leea hirta might well be sea-intro¬ 
duced if Leea sambucina is ; their fruits are very similar and Leea fruits are 
common in the “drifts.” All the fruits found, however, were precisely 
the same and seemed to be undoubtedly those of Leea sambucina, which 
is a very common species in the mud flats that skirt the mangrove- 
swamps, where it occurs as a considerable shrub or small tree with 
stilted roots that imitate the style and appearance of those of the man- 
groves. Both species, however, may have been introduced by fruit¬ 
eating birds ; only one therefore, owing to its habitat, is taken as an 
example of this mode of introduction, the other being relegated to the list 
of species that are bird-introduced. Another species to which the same 
remarks apply is Ardisia htimilis, which is a purely beach-forest species 
and, as such, is equally common here, on Narcondam, in the Andamans, 
and in the Nicobars; perhaps it is, on the whole, more likely to have been 
introduced owing to birds having eaten its purple-berried fruit. Allophy- 
lus Cobbe, which is almost cei'tainly bird-introduced, may be quoted in 
support of this, for though it also occurs in the interior it is a common 
tree in the Pandanus fence and in the beach-forest. Bracontomelum man- 
gif erum might be a sea-introduced species, for Mr. Hemsley records a 
Bracontomelum ? fruit from the New Guinea “drift”, with empty seed- 
cells however {Challenger Reports ; Botany, vol. i, part 3, p. 290). And 
if Bracontomelum be included so might Spondias and Canarium, for 
though birds and bats eat the pulpy fruits of these species they cannot 
swallow the stone and, as in the case of Terminalia Catappa, can hardly 
do more than assist in dispersing them locally. Besmodium triquetrum 
and Besmodium polycarpum are both very common on the rocky parts of 
the coast just above the spray-line and their fruits therefore are extremely 
common in the “ drifts.” But it is not at all clear that they must therefore 
192 
