1M OUTLINE OF PLANT GEOGRAPHY 



jungle belt Bkirting the foot of the great range of the Himalaya. 

 This jungle is composed for the most part of stunted scrubby trees 

 and shrubs, with coarse tall grass between. The commonest trees 

 art 1 species of Acacia, Dalbergia, Sterculia, and several others. 

 This region is notoriously malarial, and the haunt of tigers and 

 other big game. 



The change in the vegetation as one ascends from Siliguri, 

 at the base of the mountains to Darjiling, about 7,000 feet eleva- 

 tion, is very marked, and as the tiny train makes very slow prog- 

 resa along the steep and crooked track, one has ample time to 

 study the character of the forest along the railway. 



Up to an altitude of about 3,000 feet, the forest has a decidedly 

 tropical aspect, although it lies beyond the northern tropic; but 

 the southern slopes of the great mountains have abundant mois- 

 ture, arid an equable climate. 



A lofty forest replaces the scrub of the Terai and includes some 

 very large and valuable trees. Of these the most important is 

 the "Sal" (Shorea robusta), a gregarious species, and a very im- 

 portant timber-tree belonging to the peculiarly Indo-Malayan 

 family. Dipterocarpaceae. Other notable trees are the "cedar" 

 (Cedrda Toona), a wide-spread species reaching to Northern 

 Australia, and several species of Terminalia which like the cedar, 

 shed their leaves in the dry season, as many other Indian trees 

 do; Gordonia WaUichii, belonging to the Camellia family, and 

 a genus also represented in the southern United States is a common 

 tree of the sub-Himalayan forest, and several species of Ficus are 

 also characteristic of this tropical zone. 



The tropical character of this forest is most pronounced at the 

 lower levels, especially in the deep, very wet lower valleys of the 

 streams descending from the mountains. Palms, bananas, bam- 

 boos, screw-pines, huge Aroids, and other characteristic tropical 

 types abound. Few of these extend above 3,000 feet, where there 

 begins an intermingling of the temperate types characteristic 

 of the upper Himalayan forest region. Thus a pine (Pinus longi- 

 folia) occurs as low as 1,500 feet, although most of the vegetation 

 at this elevation is tropical. 



The abundant moisture, especially in the sheltered valleys 

 and gorges, favors a luxuriant growth of climbing plants and 

 epiphytes. 



