e to go over his [De
Candolle's] book and point out the several subjects in which I fancy he
is original. His remarks on the relations of naturalised plants will be
very useful to me; on the ranges of large families seemed to me good,
though I believe he has made a great blunder in taking families instead
of smaller groups, as I have been delighted to find in A. Gray's last
paper. But it is no use going on.

I do so wish I could understand clearly why you do not at all believe in
accidental means of dispersion of plants. The strongest argument which
I can remember at this instant is A. de C., that very widely ranging
plants are found as commonly on islands as over continents. It is really
provoking to me that the immense contrast in proportion of plants in New
Zealand and Australia seems to me a strong argument for non-continuous
land; and this does not seem to weigh in the least with you. I wish I
could put myself in your frame of mind. In Madeira I find in Wollaston's
books a parallel case with your New Zealand case--viz., the striking
absence of whole genera and orders now common in Europe, and (as I have
just been hunting out) common in Europe in Miocene periods. Of course
I can offer no explanation why this or that group is absent; but if the
means of introduction have been accidental, then one might expect odd
proportions and absences. When we meet, do try and make me see more
clearly than I do, your reasons.

LETTER 340. TO J.D. HOOKER. Down, November 14th [1858].

I am heartily glad to hear that my Lyellian notes have been of the
slightest use to you. (340/1. The Copley Medal was given to Sir Charles
Lyell in 1858. Mr. Darwin supplied Sir J.D. Hooker, who was on the
Council of the Royal Society, with notes for the reasons for the award.
See Letter 69.) I do not think the view is exaggerated...

Your letter and lists have MOST DEEPLY interested me. First for less
important point, about hermaphrodite trees. (340/2. See "Life and
Letters," II., page 89. In the "Origin," Edition I., page 100, the
author quotes Dr. Hooker to the effect that "the rule does not hold in
Australia," i.e., that trees are not more generally unisexual than other
plants. In the 6th edition, page 79, Darwin adds, "but if most of the
Australian trees are dichogamous, the same result would follow as if
they bore flowers with separated sexes.") It is enough to knock me down,
yet I can hardly think that British N. America and New Zealand sho