VI PREPACE. 



■ 



The low northern half of the island, shut off by the hills from 

 the rains of the south-west monsoon, has a rainy season of very 

 short duration, and is usually extremely dry during the remainder 

 of the year. 



The character of the island vegetation varies, as might be ex- 

 pected, in accordance with this difference of climatal conditions ; 

 for, whilst on the hills the flora resembles very much that of the 

 Neilgherrries, in the humid south it ia more akin to that of 

 Sumatra and the Malay Archipelago; and in the dry north of 

 the island it would seem to be nearly identical with that of the 

 Coromandel coast. 



The indigenous species enumerated in the present work 

 amount to 2832, viz. : 



Dicotyledones .' . 1959 



Monocotyledones 648 



Filices, Lycopodiacea), and Marsileacejo . 225 



Care has been taken not to multiply species unnecessarily, for 

 observation has shown that the amount of variation is often con- 

 siderable in plants affecting a large range of variation, and con- 

 sequently of climate. Insi 

 Mappia, TuTjpinia, Evony 



elevated locality produces a form or variety possessing a stouter 

 habit and larger flowers than are observed in the same species 

 when growing only a little above the level of the sea. These 

 forma or varieties would probably be viewed by some botanists in 

 the light of distinct though closely allied species, and they occupy, 

 in fact, that debatable ground the difficulties and perplexities of 

 wbicli the practical naturalist alone knows, and which, in the 

 opinion of many (and I may include myself among the number), 

 are only to be got rid of by the adoption of the views enunciated 

 by Mr. Darwin as regards the relationship of allied forms or 

 species by descent from a common ancestor. 



From the large extent of forest-land which has been and ia now 

 being appropriated to coffee cultivation, there is little doubt that 

 some of the indigenous plants will in time become exceedingly 

 rare, if not altogether extirpated, or exist only in the botanical 

 garden, into which as many kinds as possible are beifig introduced. 

 The obtrusive character, too. of a plant brought to the island 



Hortonia^ 



a more 



