32 RELATION BETWEEN CLIMATE AND VEGETATION. 



those wlio have sviperintended it have done nothing almost, either 

 for their own credit or the honour of the establisliment. Since 

 tlie publication of the little book of Linnaeus, the only work 

 which has been produced on Ceylon Botany is the ' Catalogue 

 of Plants growing in Ceylon,' published in 1824, by Mr. Moon, 

 who was then Superintendent of the Botanical Gardens — a work 

 which never was of nuich use, and which is now quite obsolete, 

 as, being merely a catalogue, there are no characters by which to 

 recognize the species he has enumerated. As connected with 

 these observations, I may remark that I am at present engaged 

 in preparing a work which will contain descriptions of all the 

 vegetable productions indigenous to Ceylon, at least so far as I 

 can obtain them, illustrated with coloured figures of some of the 

 more rare, beautiful, or useful species. This, however, will be 

 a labour of several years to come, as I have still to explore dif- 

 ferent parts of the island, the productions of which are totally 

 unknown. 



The vegetation of all countries has its general character 

 determined by two great principal causes — physical aspect and 

 clhiiate. The former having already been detailed in the preced- 

 ing geological sketch of the island, I shall here ofler a few 

 remarks on the latter. The two monsoons which occupy the 

 greater part of the year materially influence the climate. That 

 from the south-west lasts generally from April to September, 

 while the north-east prevails from November to February, the 

 intervening periods being subject to variable winds and calms. 

 The western side of the island, which is exposed to the south- 

 west monsoon, has a humid and temperate climate similar to that 

 of the Malabar coast, while the eastern, which is open to the 

 north-east monsoon, has a hot and dry climate similar to that of 

 the Coromandel coast. The seasons and climates of the south- 

 west and north-east portions of the island are therefore very 

 different. While on one side of the island the rains are falling 

 in torrents, the other is suffering from drought ; and it not unfre- 

 quently happens that the opposite sides of a single mountain 

 exhibit at the same time these opposite states of climate. 



The great variety of surface and of climate, then, which the 

 island possesses, are favourable not only to a varied, but to a 

 luxuriant vegetation, especially in its central and southern dis- 

 tricts. From the study of plants taken in connection with these 

 circumstances and their various other physical conditions, has 

 originated the science of Botanical Geography, one of the most 

 interesting branches of Botany, and one wliich some day will no 

 xloubt throw nuich light on the laws which have regulated the 

 production and dispersion of species. It is only of late years 

 that attention has been given to this subject, for, till the natural 



