EAST NEPAL AND THE SIKKIM HIMALAYA MOUNTAINS. 117 



I have here taken the Darjiling elevation of 7000 feet as the 

 standard of comparison between the Himalaya and London, and 

 of course it is understood that I here speak of the cultivation of 

 species of that zone ; but as most of the Himalayan plants have 

 a range of fully 3000 feet, which equals a mean annual diti'erence 

 of temp, of about 10°, it follows that localities with a mean 

 annual temp, of 46° to 56° are in that one respect suited to the 

 cultivation of species of the lower zone. It must also be borne in 

 mind, that the temperatures are less uniform above 7000 feet in 

 Sikkim, than at that particular elevation where the maximum 

 of moisture prevails. 



Seasons, general remarks on. — These, throughout the Hima- 

 laya, partake more or less markedly of the hot and cold, or wet 

 and dry of the plains of Bengal, with this exception, that the 

 dry westerly wind which sweeps across the plains during many 

 of the winter months is scarcely felt in Sikkim, or in the after- 

 noon only in occasional puffs from the S.AV. The southerly 

 wind blows steadily from May till November, but is not uni- 

 formly moist at all seasons; it attains its maximum of humidity 

 in July and August, when, being warmest, its capacity for trans- 

 porting moisture is also greatest. From November till April, 

 calms and light winds prevail, with occasional gales. Electric 

 disturbances are most frequent from March to May, and again 

 at the end of the rains ; they are however almost wholly con- 

 fined to the foot of the hills and outer ranges. 



The rainy season commences with a spring fall in April or 

 May, which is the flowering seasons of all the rhododendrons, 

 and of most of the magnolias of the lower zone (7000 to 10,000 

 feet). A I'emarkable uniformity of humidity and temperature 

 now prevails at all elevations, till the fruiting season, which 

 occurs in September at the upper zone, in October in the middle, 

 and November and December in the lower zone. The rains 

 have fairly " set in" by the middle or end of May, and the rho- 

 dodendron flowers are withered within a month of their flower- 

 ing, that is, by the beginning of June in both lower and middle 

 zone, and but little later above 14,000 feet ; for though they bud 

 so late in the alpine regions, vegetation proceeds there much 

 more rapidly. 



In the upper zone May is the budding month, and the resinous 

 scales that envelop the rhododendron flowers are no sooner thrown 

 off than the leaves are expanded, and the flowers follow with that 

 rapidity which is so characteristic of an arctic spring, and indeed 

 of all excessive climates. 



The distribution of the seasons in the three zones is very pecu- 

 liar, and gives rise to some anomalies that have puzzled natu- 

 ralists. From the middle of October to that of May, vegetation 



VOL. VII. K 



