218 FLORA INDTCA. 



and are hence gradually drying up. This diminution of many 

 of the lakes is no doubt entirely attributable to a change of 

 climate, which is extremely interesting in a botanical point of 



view, from its favouring the immigration of many saline types 

 of the Caspian flora. 



Where the surface is covered with salt-marshes, are found 

 Glaux maritima, Eurotia, Corispermum, Caroxylon, Suceda, 

 Salsola, Chenopodium, Ambrina, Christolea, Triglochin ; and a 

 large Nostoc, of a species eaten in China, floats on the surface 

 of the pools. The carbonate of soda again appears to have 

 no appreciable effect on the vegetation of the dry soil it en- 



tufted 



with 



Cultivation in Tibet 



is luxuriant below 12,000 feet, barley and wheat being the 



with 



The 



indigenous vegetation is everywhere scanty. Though there is 

 no forest, the banks of the rivers and streams are skirted by 



balsamift 



Myricaria, Hipj 



rar 



does Pinus eoccelsa, which is only found towards the confines 



and can hardlv be considered a Tibetan tree. My- 



Hasora 



Hippophae 



feet. 



balsamifi 



seen up to 12,000 feet ; apples, walnut, the black poplar, and 

 Elaagnus up to 11,000 feet, pears to 10,000 feet, and grapes 

 and white poplar and plane-trees to 9000 feet. 



Subtropical types ascend along the course of the Indus 



far 



Nubra 



amples : 





Capparis. Echinops. 



Peganum. Tamarix Gallica. 



Tribulus. Lycium. 



Sophora. Vincetoxicuni. 



