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Think of elevation, as known from shells, N. Wales, all Europe (a boulder formation) —

Coast of Chile — Sweden, Sicily, all volcanic islds — oscillations Gibraltar — South Italy, porphyry subsidence as much — known in N. America -

Direction of species of plants not known, nothing to contradict as long as sea-shells perhaps land shells — if so longer than sea-shells.

Then vast difference of capability of migration on newly raised ground not preoccupied —

People [anywhere] from non-migration in fully stocked districts — Then included accidents whirlwinds – buds &c &c – mostly by land — which formerly existed — Then change of climate vary in N. America — cold of ice-period, little warmer then at

[53v]

present, now colder — newer plants may have occupied whole districts & wd be left only in spots, where soil more favourable (as plants live on chalk have only while live on all lands on continents) —

Till we know, whether how any particular plant disseminates, ought not to wonder at certain species not crossing rivers — two groups meeting at central point —

We cannot prove migration, but not improbable —

Perhaps some plants may go back to Eocene time— if so !!! geographical changes mean great changes some monolithic rocks—

(Study inhabitants of coral Islets any species which inhabits several in P. probably aboriginal)