1893.] D. Prain — Flora q/"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 JSTarcondani 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 Amorphopliallus which, 

 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 ; Isclicemum muticum 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, Isclicemum 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 Narcon- 

 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 Narcondam, 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. Four are species certainly 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 Narcondam 

 climbers being so ; of these four are again sea-shore species, and the 

 Dioscorea found in both islands may be a fifth of the sea-introduced 

 class. Two, the Soyas, are wind-introductions ; one, Capparis sepiaria, is 

 certainly; another, the Abrus, is probably, a bird-introduced species. 



Of the thirty-one Narcondam shrubs, one (Musa) has been intro- 

 duced by man ; on the other hand not a single shrub owes its presence 



