of studying. I have just
bethought me that for the chance of your noticing it in the "Journal,"
I will point out the new and very remarkable facts. I have paid the poor
fellow's passage out to India, where I hope he will succeed, as he is a
most laborious and able man, with the manners almost of a gentleman.

(653/2. The following is an abstract of the paper which was enclosed in
the letter to Asa Gray.)

Pages 106-8. Red cowslip by variation has become non-dimorphic, and with
this change of structure has become much more productive of seed than
even the heteromorphic union of the common cowslip. Pages 91-2, similar
case with Auricula; on the other hand a non-dimorphic variety of P.
farinosa (page 115) is less fertile. These changes, or variations,
in the generative system seem to me very remarkable. But far more
remarkable is the fact that the red cowslip (pages 106-8) is very
sterile when fertilising, or fertilised by the common cowslip. Here we
have a new "physiological species." Analogous facts given (page 98) on
the crossing of red and white primroses with common primroses. It is
very curious that the two forms of the same species (pages 93, 94, 95,
and 117) hybridise with extremely different degrees of facility with
distinct species.

He shows (page 94) that sometimes a cross with a quite distinct species
yields more seed than a homomorphic union with own pollen. He shows
(page 111) that of the two homomorphic unions possible with each
dimorphic species the short-styled (as I stated) is the most sterile,
and that my explanation is probably true. There is a good summary to the
paper.

LETTER 654. TO J.D. HOOKER.

(654/1. The following letters to Hooker, April 1st, April 5th and May
22nd, refer to Darwin's scheme of employing Scott as an assistant at
Down, and to Scott's appointment to the Botanic Garden at Calcutta.)

Down, April 1st, 1864.

I shall not at present allude to your very interesting letter (which as
yet has been read to me only twice!), for I am full of a project which I
much want you to consider.

You will have seen Scott's note. He tells me he has no plans for
the future. Thinking over all his letters, I believe he is a truly
remarkable man. He is willing to follow suggestions, but has much
originality in varying his experiments. I believe years may pass before
another man appears fitted to investigate certain difficult and tedious
points--viz. relative fertility of varieties of plants, i