[E59]

Glacial

Nov. 21/57/

Falconer tells me Bot. garden of Saharanpur is 1000 ft in height & though about 7° N. of Tropics is as hot as within Tropics, & excessively humid - does not believe that one perennial British or even S. Spanish Plant cd survive there. Even of Australia, Proteaceæe some of which were Tropical & of which about 200 have been tried only 1 single species cd survive.

I think this very important for in the humid Tropical district cd be islands where old Equatorial plant might survive & in dozen districts colder plant might migrate

over

[in margin:] Humidity clearly great cause of destruction.

 

[E59v]

Hooker told me something about natural distribution of temperate plants descending much lower or higher on dry or damp mountains.