erms used, because I
have often been annoyed at the multitude of new terms lately invented in
all branches of Biology in Germany; and I doubted much whether I was not
quite as great a sinner as those whom I have blamed. When I read your
remarks on the word "purpose" in your "Phytographie," I vowed that I
would not use it again; but it is not easy to cure oneself of a vicious
habit. It is also difficult for any one who tries to make out the use of
a structure to avoid the word purpose. I see that I have probably gone
beyond my depth in discussing plurifoliate and unifoliate leaves; but
in such a case as that of Mimosa albida, where rudiments of additional
leaflets are present, we must believe that they were well developed in
the progenitor of the plant. So again, when the first true leaf differs
widely in shape from the older leaves, and resembles the older leaves in
allied species, is it not the most simple explanation that such leaves
have retained their ancient character, as in the case of the embryos of
so many animals?

Your suggestion of examining the movements of vertical leaves with an
equal number of stomata on both sides, with reference to the light,
seems to me an excellent one, and I hope that my son Francis may follow
it up. But I will not trouble you with any more remarks about our book.
My son will write to you about the diagram.

Let me add that I shall ever remember with pleasure your visit here last
autumn.

LETTER 761. TO J. LUBBOCK (Lord Avebury). Down, April 16th [1881].

Will you be so kind as to send and lend me the Desmodium gyrans by the
bearer who brings this note.

Shortly after you left I found my notice of the seeds in the "Gardeners'
Chronicle," which please return hereafter, as I have no other copy.
(761/1. "Note on the Achenia of Pumilio argyrolepis." "Gardeners'
Chronicle," 1861, page 4.) I do not think that I made enough about the
great power of absorption of water by the corolla-like calyx or pappus.
It seems to me not unlikely that the pappus of other Compositae may be
serviceable to the seeds, whilst lying on the ground, by absorbing the
dew which would be especially apt to condense on the fine points and
filaments of the pappus. Anyhow, this is a point which might be easily
investigated. Seeds of Tussilago, or groundsel (761/2. It is not clear
whether Tussilago or groundsel (Senecio vulgaris) is meant; or whether
he was not sure which of the two plants becomes slimy when wette