| → views 1859 1860 1861 1866 |
| considerations 1869 |
| considerations to be 1872 |
|
| → whilst in this incipient state 1859 1860 1861 1866 |
| OMIT 1869 1872 |
|
| → Madeira. 1859 1860 1861 1866 |
| Madeira, and with plants by Gaston de Saporta. 1869 1872 |
|
| →
much-diffused,
1866 1869 |
|
,
much diffused
,
1872 |
|
|
species; but whether this belief
justifiable must be judged
by the
weight of the
facts and
→views
given throughout this work. |
|
| It need not be supposed that all varieties or incipient species
attain the rank of species. They may
→whilst in this incipient state
become extinct, or they may endure as varieties for very long periods, as has been shown to be the case by Mr. Wollaston with the varieties of certain fossil land-shells in
→Madeira. If a variety were to flourish so as to exceed in numbers the parent species, it would
rank as the species, and the species as the variety; or it might come to supplant and exterminate the parent species; or both might co-exist, and both rank as independent species. But we shall hereafter
to
this subject. |
|
| From these remarks it will be seen that I look at the term
as one arbitrarily
for the sake of
to a set of individuals closely resembling each other, and that it does not essentially differ from the term variety, which is given to less distinct and more fluctuating forms. The term variety, again, in comparison with mere individual differences, is also applied arbitrarily,
for
sake. |
|
→
much-diffused,
and
common
Species
vary
most.
|
| Guided by theoretical considerations, I thought that some interesting results might be obtained in regard to the nature and relations of the species which vary most, by tabulating all the varieties in several well-worked floras. At first this seemed a simple task; but Mr. H. C.
to whom I am much indebted for valuable advice and assistance on this subject, soon convinced me that there were many difficulties, as did subsequently Dr. Hooker, even in stronger terms. I
|
