1 1 1 o Ward . — Some Plant Formations from Western China. 
trenches where flow the Salween and Mekong rivers in the real semi-desert 
regions. On the whole perhaps the arid regions of Western China present 
features more interesting to the geologist than to the botanist, since we And 
practically the same adaptations to combat the hostile conditions here 
as are found in waterless regions elsewhere ; nevertheless, a comprehensive 
survey of the flora and its various morphological peculiarities, with a know- 
ledge of all the physical conditions which react on the vegetation, would be 
most instructive when we come to deal with distribution. For it is just 
these deep semi-desert valleys which intervene between the Himalayan 
flora and the flora of Western China. 
