and am thoroughly ashamed of my inaccuracy.
(695/1. See "Fertilisation of Orchids," Edition II., page 46, where
Lord Farrer's observations on the movement of the pollinia in Ophrys
muscifera are given.) I find that the pollinia do not move if kept in a
very damp atmosphere under a glass; so that it is just possible, though
very improbable, that I may have observed them during a very damp day.

I am not much surprised that I overlooked the movement in Habenaria, as
it takes so long. (695/2. This refers to Peristylus viridis, sometimes
known as Habenaria viridis. Lord Farrer's observations are given in
"Fertilisation of Orchids," Edition II., page 63.)

I am glad you have seen Listera; it requires to be seen to believe in
the co-ordination in the position of the parts, the irritability,
and the chemical nature of the viscid fluid. This reminds me that
I carefully described to Huxley the shooting out of the pollinia in
Catasetum, and received for an answer, "Do you really think that I can
believe all that!" (695/3. See Letter 665.)

LETTER 696. TO J.D. HOOKER. Down, December 2nd, 1868.

It is a splendid scheme, and if you make only a beginning on a "Flora,"
which shall serve as an index to all papers on curious points in the
life-history of plants, you will do an inestimable good service. Quite
recently I was asked by a man how he could find out what was known on
various biological points in our plants, and I answered that I knew of
no such book, and that he might ask half a dozen botanists before one
would chance to remember what had been published on this or that point.
Not long ago another man, who had been experimenting on the quasi-bulbs
on the leaves of Cardamine, wrote to me to complain that he could not
find out what was known on the subject. It is almost certain that some
early or even advanced students, if they found in their "Flora" a
line or two on various curious points, with references for further
investigation, would be led to make further observations. For instance,
a reference to the viscid threads emitted by the seeds of Compositae, to
the apparatus (if it has been described) by which Oxalis spurts out its
seeds, to the sensitiveness of the young leaves of Oxalis acetosella
with reference to O. sensitiva. Under Lathyrus nissolia it would [be]
better to refer to my hypothetical explanation of the grass-like leaves
than to nothing. (696/1. No doubt the view given in "Climbing Plants,"
page 201, that L.