From Francis Galton   16 February 1876

42 Rutland Gate

Feb 16. 1876

My dear Darwin

Will the Enclosed be sufficient? if not pray tell me, & I can get you more in a few days. I too am experimenting in the same direction & shall be curious to know hereafter, how far my results may accord with yours.

I send a larger variety than you asked for, as I think the medium produce of medium peas will be found useful as a standard.1

What I send are.

(1) Big seeds,—the produce of big seeds (L)

(a) of L size

(b) of above L size.

(2) Little seeds,—the produce of big seed (L size)

(a) of P size

(b) of below P.

(3) Medium seeds (N)—the produce of medium seeds (N)

(4) Small seeds the produce of small (P) seeds

(a) very small size (much mishapen as nearly all of this lot are) much under Q size.

(b) small. (P size)

By “size” please understand “weight”

Pray excuse their being put up in rather clumsy packets—but I am obliged to go out early & wished to write before I went.

Ever sincerely yrs | Francis Galton

weight of{L—1.58grains2diff. 0.172 gr
1 pea ofN—1.23"←(M. 1.41)
P—0.89"←(0. 1.0)
Q—0.72"

[Enclosure]

Large peas (L)

taken out of moderately sized pods (I have kept for planting all those from large pods)

the produce of large peas (L)

also a few peas larger than L out of same lot

These are heavier than L (nearly K)

Small peas P

the produce of large (L) peas

Also some still smaller from the same lot

Peas lighter than P (P-Q or Q) the produce of L

Medium peas (N) taken out of medium pods the produce of medium peas (N)

Very small seeds, the produce of small (P) seeds

also small P seeds of the same lot

Mem The produce of these generally appear misshapen. I can hardly pick out a single well shaped small pea out of the particular lot from which the enclosed were taken, whereas the produce of the large (L) seeds sown in the same garden are all shapely.

(P) size the produce of P plants

No letter from CD to Galton requesting seeds has been found, but CD was one of several friends assisting Galton in his experiments on sweetpeas (Lathyrus odoratus), planting seeds of different sizes and observing the progeny (see Correspondence vol. 23, letter from Francis Galton, 2 June 1875). Galton’s results were presented at the 9 February 1877 meeting of the Royal Institution of Great Britain and published in the institution’s proceedings and also in Nature (Galton 1877a, 1877b).
A grain (based on the average weight of a seed of wheat) is equivalent to 64.79891 milligrams.

Please cite as “DCP-LETT-10395,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-10395