395 
The list is so short that an analysis of it is nnnecessary; it is suffi¬ 
cient to note that the possibility of introduction from Malaya or from 
Indo-China is, so far as its evidence goes, evenly balanced. 
While the two lists probably include all the species usually intro¬ 
duced by being attached externally to birds they do not exhaust all the 
possibilities of the case. For, if the mud of a marsh may fix the seeds 
or fruits of paludine species to the feet or head of wading-birds, other 
substances may fix the seeds of forest species to the bodies of forest-birds. 
There is almost no limit to the number of species that might be suggested 
as introduced in this way, provided their seeds be sufficiently small; this 
very circumstance, combined with the necessarily hypothetical nature of 
the subject, makes it impossible to attempt the suggestion of this mode 
of dispersal in connection with any particular species.* 
The next kind of “ bird-introduced ” species to be considered—those 
introduced in consequence of having been eaten—may also be con¬ 
veniently divided into two sub-groups; one consisting of species where 
dissemination by birds is an every-day process, the other consisting of 
species that can only be occasionally disseminated in this fashion since 
the process implies the destruction of the bird itself. 
The first sub-group corresponds fairly closely with those species 
* The following facts will shew that, though necessarily hypothetical, the sub¬ 
ject is not far-fetched but is, on the contrary, highly deserving of attention. When 
in Narcondam the writer was particularly anxious to obtain the seeds of a species of 
Bombax present there, for sowing at Calcutta; for some days the search was hopeless 
because the capsules as they ripen are broken open and the seeds are eaten by a 
species of Horn-bill that is common in the island, while any seeds that escape the 
birds and fall to the ground are devoured by the rats that swarm in the place. At 
length under one tree, where there happened to be on the under-growth one or two 
large spider’s webs, four seeds were found sticking in these webs ; these were the 
only seeds he was fortunate enough to obtain ; they were brought to Calcutta, 
germinated there, and the four young trees are now alive in the Botanic Garden. 
This will shew that seeds easily may, and at times do, stick in spider’s webs. 
In spring 1890 a Barbet was found lying on the ground in the Botanic Garden 
unable to fly ; on being picked up and examined it was found that its left wing and 
left leg were flxed together by means of a spider’s web; on freeing these it was found 
that the toes of its left foot were further bound up in a ball and the flight-feathers 
were firmly tied together. When finally completely freed from its entanglement the 
bird flew away, frightened, but physically uninjured. This will shew that birds do 
sometimes come in contact with spider’s webs and that these are capable not merely 
of fixing objects to a bird’s feathers but of fixing these feathers so that the bird itself 
cannot move them. 
All that is therefore required in order to establish the truth of the hypothesis 
is direct observation of a bird having come in contact with a spider’s web which 
happened to have seeds lodged in it at the time, and of its carrying away seeds and 
web together. 
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