I write to ask you what you think of the following idea as to a possible method of attacking Pangenesis. Why not, I mean, inarch, at an early period of their growth, the seed-vessels or ovaries of plants belonging to different varieties? If adhesion takes place, the ovary might then be severed from its parent plant, and left to develop upon the foreign one. If you think this a possible experiment, now would be the time of year to try it. Therefore I write to ask whether you do think it possible, and if so, what plants you may think it would be best to try it with. All the cats[31] I have hitherto let out of their respective bags have shown themselves exceedingly stupid, not one having found her way back. Very sincerely and most respectfully yours, GEO. J. ROMANES. _From C. Darwin, Esq., to G. J. Romanes._ Down, Beckenham, Kent: March 26, 1881. You are very plucky about Pangenesis, and I much wish that you could have any success. I do not understand your scheme. Do you intend to operate on an ovarium with a single ovule, and to bisect it after being fertilised? I should fear that this was quite hopeless. If you intend to operate on ovaria with many seeds, whether before or after fertilisation, I do not see how you could possibly distinguish any effect from the union of the two ovaria. Any operation before fertilisation would, I presume, quite prevent the act; for very few flowers can be fertilised if the stem is cut and placed in water. Gärtner, however, says, that some Liliaceæ can be fertilised under these circumstances. If Hooker is correct, he found that cutting off or making a hole into the summit of the ovarium and then inserting pollen caused the fertilisation of the ovules. This has always stretched my belief to the cracking point. I think he has published a notice on this experiment, but forget where, and I think it was on 'Papaver.' Dyer could probably tell you about it. Perhaps your plan is to remove one half of the ovarium of a one-seeded plant and join it on to the ovary of another of a distinct var., with its ovule removed; but this would be a frightfully difficult operation. I am very sorry to hear about your ill success with cats, and I wish you could get some detailed account of the Belgium trials. Yours very sincerely, C. DARWIN. April 16, 1881. My manuscript on Worms has been sent to printers, so I am going to amuse myself by scribbling to you on a few points; but you must not waste your time in answering at any length this scribble. Firstly, your letter on intelligence was very useful to me, and I tore up and rewrote what I sent you. I have not attempted to define intelligence, but have quoted your remarks on experience, and have shown how far they apply to worms. It seems to me, that they must be said to work with some intelligence, anyhow, they are not guided by a blind instinct.