386 



D. Praia — The Vegetation of the Coco Group. 



[No, 4, 



fire. The effects of actual ctarring were, however, observed in the 

 hollow trunk of a large Mimusojos near the shelter huts at the south end 

 of Great Coco ; closer comparison shows that the product of the Fungus 

 has a facies of its own unlike that of true charcoal. This difference is 

 difficult to express in words, but is very recognisable when the two things 

 are placed side by side. The phenomenon was not noticed in the case 

 of Erythrina, Heritiera, Stephegyne, or other dead trees on the beach. 



Excluding from consideration all the doubtful species enclosed, in 

 brackets we find that there are 80 unequivocally sea-introduced plants, or 

 more than one-fourth of the phanerogamic species and over 22 per cent, of 

 the entire flora. On consulting the distribution it is seen how greatly the 

 coast flora is one characteristic of the Indian Ocean and of Malayan Seas, 

 particularly the latter, since 76 species, or 97 per cent., occur on the shores 

 of the Malay Islands, whereas only 66, or 83 percent., occur on the Indian 

 coasts of the Sea of Bengal. Moreover one of these, Sarcolobus globosus, 

 might almost be omitted, its only Indian locality being the Sunderbuns, at 

 the head of the Bay of Bengal. Another, Ipomcea denticulata, though ex- 

 tending up the eastern side of the Bay to the coast of Arracan, is, on the 

 western side, confined to Ceylon. This indication of a tendency to ex- 

 tension eastward is borne out by the features of the further distribution 

 of these species, for 60 species, or 76 per cent., extend south-eastward 

 to the shores of northern Australia, while only 47, or 59 per cent., extend 

 south-west to the Mascarene Islands ; and 51 species, or 64 per cent., 

 occur in one or other of the Polynesian groups, while only 36, or 46 per 

 cent, reach continental East Africa. But, while this is the case, it is inter- 

 estino-to note that 21 species, or 24 per cent., occur on the AfricauAtlantio 

 coast, and 15 species, or 19 per cent., cross the Atlantic to the Eastern 

 coasts of America, whereas only 1 3 species, or 16 per cent., extend across 

 the Pacific from Polynesia to the Western American coasts. These fea- 

 tures of the littoral floi'a are given more compactly in the subjoined table. 



Table XV. Extension of " littoral " species present in the Coco Group. 



Species 

 extending westward to 



Species 

 present in the 



Species 

 extending eastward to 



-♦J 

 ai 

 cS 

 O 



a 



ca.2 



CO 

 03 



IS .2 



o 



< 



W 



CO 



a3 



a 



1 



o 



a 



c3 



c3 

 .1-1 



1— 1 



Coco Group. 



6 



I 



1 



Is 



1 



02 



P 



'S 



'o 



0-1 



m 



o 



o o 



« 3 



15 



21 



36 



47 



66 



80 



76 



60 



51 



13 



19% 



24% 



46% 



59% 



83% 



100% 



977o 



767o 



64.% 



i67o 



