My dear Hooker

I never for a moment dreamed of your deferring the publication of your paper, & it would be a pity. But of course I shall be very glad to mention any of the facts which illustrate my work, & this will be of the highest value to me, as others will believe far more readily what you have also seen, than what I have alone, who am no botanist.— I do not suppose I shall begin printing for 3 or 4 months, as my matter is spreading out.² But the time will largely depend on health.

I think from my own trials that the colour of litmus paper would show you whether the fluid was rendered more acid (1) by mechanical irritation, in comparison to what it was before & (2^d) by the addition of a few drops of the infusion of raw meat, but you w^d have to observe how far this addition by itself at once affected the litmus paper.— If you knew before hand the appearance of the glands in a virgin pitcher, you w^d be able to learn after giving the infusion of raw meat— whether this caused aggregation like that from C. of Ammonia. It ought to do so judging from Drosera, & this w^d be an important fact to learn.³

It is precious easy to suggest experiments, & often most difficult, as I know to my cost, to carry them out. But I would in your case cut out a rather large square hole (or fistula) on one side of pitcher, (I did this with Dionæa & it not prevent leaf acting)

Empty fluid & dry with blotting paper opposite side of pitcher, & then after a time I sh^d. think you would see beads of secretion on the glands.— I enclose some fibrin which must be kept in glycerine, & can easily be washed before being used. I would at the same time stick on a bit (after pressing it a little between blotting paper) on opposite side of Pitcher & see if this does not increase or quicken the secretion & its acid reaction. I sh^d not be surprised if it made secretion in 10′ or 15′. As a control experiment you could stick on a bit of equally damp cotton or moss on another point.— Possibly fibrin as it decays may become feebly acid, so look out for this.—

It was much better for me to receive leaves of Eucalyptus & Acacia selected by hazard

Let me have Lathyrus nissolia seeds, as soon as you have any

I will settle about Mimosa albida, when I have examined, on my return from London, Aca. farnesiana.⁴

You understand that any plant of any Family with a terminal or any lateral leaflets greatly reduced in size would be very interesting to me for studying its spontaneous movement; but Leguminoseæ w^d. be best—

I have not received from Rollisson the Eucalyptic & Australian Acacias:⁵ perhaps he has none, & puts the names in his list for ornament. I must try & come to Kew.— What an evil it is to be so easily knocked up; but I am sure that D^r Clarke is doing me good, though I am tired enough this evening⁶

Yours affect | Ch Darwin.

Very many thanks for the names, including so many specific names!!⁷ Hurrah.—

P.S. Even little cube of the hardest cartilage from raw joint of sheep is completely softened & partly dissolved in 48^o by Drosera: whereas cold water of course effects nothing.— This is a very striking, but not really more remarkable experiment than the same with roast meat or albumen.