JOURNAL 



OP THE 



ASIATIC SOCIETY OF BENGAL. 



Vol. LXII, Part II.— NATURAL SCIENCE. 

 No. II.— 1893. 



On the Flora of Narcondam and Barren Island. — By D. Prain. 



Plates III and IV. 



[Read May 3rd]. 



§ Introductory Sketch. 



The Indian Ocean is broken on the north by the Indian Peninsula 

 into two roughly triangular seas. The eastern, rather the smaller, forms 

 an area known vaguely as the Bay, Gulf, or Sea of Bengal — the first 

 of these names being that most usually employed — bounded on the west 

 by Ceylon and India, on the east by the Malay Isthmus (Tenasserim) 

 and Indo-China, and on the north by the Gangetic Delta. The ocean- 

 surface thus defined is, however, further differentiated into three distinct 

 bydrographical areas. 



These areas are (a) the Bat op Bengal, a bight limited to the west 

 by the Kistna Delta, to the east by Cape Negrais and situated to the 

 north of an arbitrary line — the parallel of Lat. 16° N. — beyond which 

 it passes into (6) the Sea of Bengal, stretching from Coromandel 

 and Ceylon, on the west, to the Andamans and Nicobars on the east. 

 The Sea of Bengal opens southwards into the Indian Ocean proper, from 

 which it is hydrographically rather definitely limited by the somewhat 

 rapid upward shelving of its floor from the bottom of that ocean to a 

 uniform depth of 2200 fathoms along a line roughly coincident with 

 the parallel of Lat. 6° K Thereafter its floor is a plain and practically 

 J. ii. 6 



