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Morphological species, that
is, forms which differ to an amount that would justify their
being considered good species, have been produced in plenty
through selection by man out of variations arising under
domestication or cultivation. The facts just given are therefore
of some scientific importance, for they tend to show that a
physiological species can be and is produced in nature out of the
varieties of a pre-existing closely allied one. This is not an
isolated case, for I observed in the course of my travels a
number of similar instances. But in very few has it happened that
the species which clearly appears to be the parent, co-exists
with one that has been evidently derived from it. Generally the
supposed parent also seems to have been modified, and then the
demonstration is not so clear, for some of the links in the chain
of variation are wanting. The process of origination of a species
in nature as it takes place successively, must be ever, perhaps,
beyond man's power to trace, on account of the great lapse of
time it requires.


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