Personal Narrative Of Travels To The Equinoctial Regions Of America During The Years 1799-1804 - Volume 1 - By Alexander Von Humboldt And Aime Bonpland.
- Page 658 of 779 - First - Home
(See The Nova Genera Et Species
Plantarum Volume 1 Page 25.)) How Can We Conceive The Migration Of
Plants Through Regions Now Covered By The Ocean?
How have the germs
of organic life, which resemble each other in their appearance, and
even in their internal
Structure, unfolded themselves at unequal
distances from the poles and from the surface of the seas, wherever
places so distant present any analogy of temperature?
Notwithstanding the influence exercised on the vital functions of
plants by the pressure of the air, and the greater or less
extinction of light, heat, unequally distributed in different
seasons of the year, must doubtless be considered as the most
powerful stimulus of vegetation.
The number of identical species in the two continents and in the
two hemispheres is far less than the statements of early travellers
would lead us to believe. The lofty mountains of equinoctial
America have certainly plantains, valerians, arenarias,
ranunculuses, medlars, oaks, and pines, which from their
physiognomy we might confound with those of Europe; but they are
all specifically different. When nature does not present the same
species, she loves to repeat the same genera. Neighbouring species
are often placed at enormous distances from each other, in the low
regions of the temperate zone, and on the alpine heights of the
equator. At other times (and the Silla of Caracas affords a
striking example of this phenomenon), they are not the European
genera, which have sent species to people like colonists the
mountains of the torrid zone, but genera of the same tribe,
difficult to be distinguished by their appearance, which take the
place of each other in different latitudes.
Enter page number
PreviousNext
Page 658 of 779
Words from 178811 to 179085
of 211363
