1856.] Herbarium of the Calcutta Botanic Garden. 415 



sea, but north of the tropic the boundaries of India are traced on 

 land, and are more or less artificial. 



The Indian Peninsula includes two distinct mountain systems. 

 The meridional chain of the Ghats attains in Travancore and Mala- 

 bar an elevation of 8,000 feet, but north of Nagar rarely more than 

 4000. It runs parallel to the western coast, and sends off trans- 

 verse chains running east, which are flattened out into a table-land 

 highest in the south, where the continent is narrow, lower to the 

 north where the continent is wider and the rivers larger. North of 

 the Godavery the transverse range of the Yindhia runs from sea 

 to sea almost on the tropic, sending out on all sides table topped 

 branches and connected by a low ridge with the ghats further south, 

 and with the Himalaya by the curious oblique Arawali range, 

 which forms a water-shed between the Indus and Ganges. 



An extensive plain watered by the Indus on the one hand and by 

 the Ganges on the other, separates the Indian Peninsula from the 

 Himalaya, which rises on the north a stupendous barrier, consti- 

 tuting the Indian portion of the enormous mountain mass of Cen- 

 tral Asia, which presents steep declivities in all directions. 



After the configuration and elevation of the land, the most 

 important element by which the distribution of vegetable forms is 

 regulated, is climate. The climate of India depends mainly on the 

 rain-fall. Situated entirely in the northern hemisphere, and with 

 an enormous mass of land to the north, the summer winds blow 

 strongly from the south, while the winter winds are northerly. The 

 south wind commonly called the S. "W. monsoon is always a sea 

 wind and therefore brings rain. The summer is therefore the rainy 

 season in India. The northern winter wind is generally a land 

 wind, so that the winters are generally dry. To this, there are two 

 exceptions, the coast of the Carnatic and the Malayan Peninsula, in 

 both of which the N. E. monsoon is a sea-breeze and therefore a 

 rain bringing wind. 



The normal climate of India is divided into a cold, hot and rainy 

 season, but the amount of rain depends on the position of each 

 place. The west coast of the Peninsula, which presents to the 

 S. W. wind a lofty range of mountains, is extremely rainy at one 

 season, but the east coast, being sheltered by the higher hills to the 

 westward, is much less so. On the Ghats the rain-fall diminishes as 



3 i 



