390 
It will be seen that the majority of the species in this table are 
actually present in one or other of the two volcanic islands of the An¬ 
daman Sea, Narcondam and Barren Island, and even in these cases where 
they are not present allied species are. There is a Bonibax in Narcon- 
dam and though its specific identity or otherwise with the Andamans 
one cannot be here discussed, it is evident that any Bomlax may be 
wind-introduced. And whatever agency explains the presence of Boni- 
hax will, part passu, explain that of Eriodendron. 
Not a single orchid was found on Narcondam thoirgh on Barren 
Island two were found—a species of Bendrobium on trees on the outer 
cone, and PhoUdota imbricata, which occurs at the top of the inner 
cone within the crater-cup where the ground is kept moist by the con¬ 
densation of escaping steam. Then the Hoyas are both present in great 
abundance on the exposed rocks and tall trees of both islands. The 
most doubtful species uudoubtly ax-e Aristolochia tagala, Oloriosa superba, 
and, especially, the two species of Dioscorea. Tet these must all be 
immigrant. The writer has collected Aristolochia tagala on Batti 
Malv, a small outlying uninhabited fragment of the Nicobar Group, 
on Bai’ren Island, and on Nax’condam. And even if it be claimed that 
on Batti Malv the species may be a remanent one on the other two 
islands it, like every other species, must be immigrant. The case of 
Gloriosa superba has already been discussed when dealing with the 
species iuti-oduced by the sea. The Dioscoreas ai’e still more difficult 
to explain, but it hai’dly seems as if they could be bird-introduced, and 
it is almost as difficult to think that they have been introduced by the 
sea. They are never littoi’al, being even in these islands strictly con¬ 
fined to the higher diy ridges. Yet they are certainly not necessarily 
remanent, for the winter has collected not these only but a third 
species, Bioscorea bulbifera, or at all events a bulbifei’ous one, which is 
present along with these two in great quantity in Narcondam and 
especially in Barren Island. In both these islands the species must 
all be immigrant and from the physiographical history of Bainen 
Island should there be, biologically speaking, extremely x’ecently so. 
Though no Strophanthus occurs in Barren Island, an Aganosma is 
common there. The distribution of the Cryptogams of this class calls 
for little remark, the peculiarities displayed in this respect by the 
Fungi being probably altogether owing to this class being imperfectly 
known in most floi’as. The jxresence, for instance, of two species here 
that ai’e I’ecorded only from North America probably implies that they 
ai’e both in reality cosmopolitan or nearly so. 
To the 58 species enumei’ated above should be added six imperfectly 
represented Cryptogams, giving a total of 64 species ; the following table 
contains an analysis of their distribution. 
200 
