your expressing yourself as an unbeliever in the eternal immutability of
species. Your final remarks on my work are too generous, but have given
me not a little pleasure. As for criticisms, I have only small ones.
When you speak of "moderate range of variation" I cannot but think that
you ought to remind your readers (though I daresay previously done) what
the amount is, including the case of the American bog-mammoth. You speak
of these animals as having been exposed to a vast range of climatal
changes from before to after the Glacial period. I should have thought,
from analogy of sea-shells, that by migration (or local extinction when
migration not possible) these animals might and would have kept under
nearly the same climate.

A rather more important consideration, as it seems to me, is that the
whole proboscidean group may, I presume, be looked at as verging towards
extinction: anyhow, the extinction has been complete as far as Europe
and America are concerned. Numerous considerations and facts have led
me in the "Origin" to conclude that it is the flourishing or dominant
members of each order which generally give rise to new races,
sub-species, and species; and under this point of view I am not at all
surprised at the constancy of your species. This leads me to remark that
the sentence at the bottom of page [80] is not applicable to my
views (143/2. See Falconer at the bottom of page 80: it is the old
difficulty--how can variability co-exist with persistence of type? In
our copy of the letter the passage is given as occurring on page 60,
a slip of the pen for page 80.), though quite applicable to those who
attribute modification to the direct action of the conditions of life.
An elephant might be more individually variable than any known quadruped
(from the effects of the conditions of life or other innate unknown
causes), but if these variations did not aid the animal in better
resisting all hostile influences, and therefore making it increase in
numbers, there would be no tendency to the preservation and accumulation
of such variations--i.e. to the formation of a new race. As the
proboscidean group seems to be from utterly unknown causes a failing
group in many parts of the world, I should not have anticipated the
formation of new races.

You make important remarks versus Natural Selection, and you will
perhaps be surprised that I do to a large extent agree with you. I could
show you many passages, written as