Flora of Narcondam and Barren Island. 
85 
are plants that may have been introduced by the sea. Of inland 
herbaceous species which may have been introduced by fruit-eating or 
marsh birds, or by the wind, the islands do not have one in common. 
In Harcondam there are four Gompositce most probably introduced 
by wind ; a grass, Thsyanolcena, may conceivably have been introduced in 
the same way. The two remaining herbs are the Amorphophallus v^hich, 
even if in this island it has developed into a distinct form, must have 
originally been introduced by some fruit-eating bird, and the Pollia, 
which most probably has been introduced by the same agency. 
In Barren Island, the wind-introduced species are two orchids and 
one grass, Pogonatherum; IscTicemum muticuni has probably been intro¬ 
duced by the sea. The others have been introduced by birds; Physalis 
and Mitreola probably by fruit-eating birds ; Oldenlandia, Vandellia and 
Oplismenus by birds to whose feet or feathers seeds have clung. Except 
Pogonatherum, Ischcemum and Mitreola, the Barren Island herbs are 
scarce. 
The paucity of armed climbers in both islands is striking. The 
proportion of climbers to erect species is considerably higher in ISTarcon- 
dam, where they form one-third of the whole Phanerogamic flora, than 
in Barren Island, where they form only one-fourth, and partly in con¬ 
sequence of this, the jungle in Barren Island is opener than in Nar- 
condam. Of the thirty-seven climbers in ISTarcondam, twelve have 
undoubtedly been introduced by fruit-eating birds, while one has most 
probably been introduced by its fruits having stuck to the feathers of 
some bird ; fourteen have been introduced by the sea; six by winds. 
Of the remaining four species, which are more doubtful, two may be 
safely assumed to be here sea-introduced species also; one may be put 
down to the agency of birds, and only one species, the Dioscorea, is 
quite doubtful; perhaps the sea is on the whole the most likely agency. 
Similarly, of the sixteen climbers on Barren Island, five are clearly 
species introduced by fruit-eating birds ; to these a sixth probably 
should be added. Pour are species cei’tainly sea-introduced ; to these 
another should probably, and two more should perhaps be added ; of 
wind-introduced species there are three. 
Very few of these species are common to both islands, only nine, 
or about half the Barren Island and one-fourth of the Harcondam 
climbers being so ; of these four are again sea-shore species, and the 
Pioscorea found in both islands may be a fifth of the sea-introduced 
class. Two, the Hoyas, are wind-introductions ; one, Capparis sepiaria, is 
certainly; another, the Abrus, is probably, a bird-introduced species. 
Of the thirty-one E'arcondam shrubs, one has been intro¬ 
duced by man ; on the other hand not a single shrub owes its presence 
299 
