nissolia has been evolved from a form like L. aphaca.)
Under a twining plant you might say that the upper part of the shoot
steadily revolves with or against the sun, and so, when it strikes
against any object it turns to the right or left, as the case may be.
If, again, references were given to the parasitism of Euphrasia,
etc., how likely it would be that some young man would go on with the
investigation; and so with endless other facts. I am quite enthusiastic
about your idea; it is a grand idea to make a "Flora" a guide for
knowledge already acquired and to be acquired. I have amused myself by
speculating what an enormous number of subjects ought to be introduced
into a Eutopian (696/2. A mis-spelling of Utopian.) Flora, on the
quickness of the germination of the seeds, on their means of dispersal;
on the fertilisation of the flower, and on a score of other points,
about almost all of which we are profoundly ignorant. I am glad to read
what you say about Bentham, for my inner consciousness tells me that
he has run too many forms together. Should you care to see an elaborate
German pamphlet by Hermann Muller on the gradation and distinction of
the forms of Epipactis and of Platanthera? (696/3. "Verhand. d. Nat.
Ver. f. Pr. Rh. u. Wesfal." Jahrg. XXV.: see "Fertilisation of Orchids,"
Edition II., pages 74, 102.) It may be absurd in me to suggest, but I
think you would find curious facts and references in Lecoq's enormous
book (696/4. "Geographie Botanique," 9 volumes, 1854-58.), in Vaucher's
four volumes (696/5. "Plantes d'Europe," 4 volumes, 1841.), in
Hildebrand's "Geschlechter Vertheilung" (696/6 "Geschlechter Vertheilung
bei den Pflanzen," 1 volume, Leipzig, 1867.), and perhaps in Fournier's
"De la Fecondation." (696/7. "De la Fecondation dans les Phanerogames,"
par Eugene Fournier: thesis published in Paris in 1863. The facts noted
in Darwin's copy are the explosive stamens of Parietaria, the submerged
flowers of Alisma containing air, the manner of fertilisation of
Lopezia, etc.) I wish you all success in your gigantic undertaking;
but what a pity you did not think of it ten years ago, so as to have
accumulated references on all sorts of subjects. Depend upon it, you
will have started a new era in the floras of various countries. I can
well believe that Mrs. Hooker will be of the greatest possible use to
you in lightening your labours and arranging your materials.

LETTER 697. TO J.D. HOOKER. Down, December 5t