. With respect to the seeds, I suppose that
one is a Carex; the other looks like that of Rumex, but is enclosed in a
globular capsule. The Pinguicula grew on marshy, low, mountainous land.

I hope you will think this subject sufficiently interesting to make you
willing to aid me as far as you can. Anyhow, forgive me for being so
very troublesome.

LETTER 726. TO J.D. HOOKER. Down, August 30th [1874].

I am particularly obliged for your address. (726/1. Presidential address
(Biological Section) at the Belfast meeting of the British Association,
1874.) It strikes me as quite excellent, and has interested me in the
highest degree. Nor is this due to my having worked at the subject, for
I feel sure that I should have been just as much struck, perhaps more
so, if I had known nothing about it. You could not, in my opinion, have
put the case better. There are several lights (besides the facts) in
your essay new to me, and you have greatly honoured me. I heartily
congratulate you on so splendid a piece of work. There is a misprint at
page 7, Mitschke for Nitschke. There is a partial error at page 8, where
you say that Drosera is nearly indifferent to organic substances. This
is much too strong, though they do act less efficiently than organic
with soluble nitrogenous matter; but the chief difference is in the
widely different period of subsequent re-expansion. Thirdly, I did not
suggest to Sanderson his electrical experiments, though, no doubt, my
remarks led to his thinking of them.

Now for your letter: you are very generous about Dionoea, but some of
my experiments will require cutting off leaves, and therefore injuring
plants. I could not write to Lady Dorothy [Nevill]. Rollisson says that
they expect soon a lot from America. If Dionoea is not despatched, have
marked on address, "to be forwarded by foot-messenger."

Mrs. Barber's paper is very curious, and ought to be published (726/2.
Mrs. Barber's paper on the pupa of Papilio Nireus assuming different
tints corresponding to the objects to which it was attached, was
communicated by Mr. Darwin to the "Trans. Entomolog. Soc." 1874.); but
when you come here (and REMEMBER YOU OFFERED TO COME) we will consult
where to send it. Let me hear when you recommence on Cephalotus or
Sarracenia, as I think I am now on right track about Utricularia, after
wasting several weeks in fruitless trials and observations. The negative
work takes five times more time than the positive.