# To Charles Lyell   31 October [1867]1

Down. | Bromley. | Kent. S.E.

Oct 31st.

My dear Lyell

Emma2 has got a bad-headach, so I write direct to you— Mr. Weale sent to me from Natal a small packet of dry locust-dung, under $\frac{1}{2}$ oz, with the statement that it is believed that they introduce new plants into a district. This statement, however, must be very doubtful. From this packet, 7 (seven) plants have germinated, belonging to at least two kinds of grasses. There is no error, for I dissected some of the seeds out of the middle of the pellets.3 It deserves notice that Locusts are sometimes blown far out to sea; I caught one 370 miles from Africa, & I have heard of much greater differences.

You might like to hear the following case as it relates to a migratory bird, belonging to the most wandering of all orders, viz. the Woodcock. The tarsus was firmly coated with mud weighing when dry nine grains, & from this the Juncus bufonius or Toad-rush germinated.4 By the way the Locust case verifies what I said in the ‘Origin’ that many possible means of distribution would be hereafter discovered.5 I quite agree about the extreme difficulty of the distrib: of land Mollusca. You will have seen in the last edit: of ‘Origin’ that my observations on the effect of sea water have been confirmed.6 I still suspect that the legs of birds which roost on the ground may be an efficient means; but I was interrupted when going to make trials on this subject & have never resumed it.7

We shall be in London in the middle or latter part of Novr. when I shall much enjoy seeing you. Emma sends her love & many thanks for Lady Lyell’s note.8

Yours very sincerely | Ch. Darwin

P.S. My brother is at home now— You can of course, use anything in this note.9

## Footnotes

The year is established by the relationship between this letter and the letter from J. P. M. Weale, 7 July 1867.
James Philip Mansel Weale had enclosed a packet of locust dung with his letter of 7 July 1867. In his Experimental notebook (DAR 157a: 83), CD recorded that ‘the dung was put on burnt sand’ on 27 August 1867, and by 6 September two grass seeds had germinated. Further germinations were recorded on 7, 9, and 24 September, and on 17 October, CD concluded that seven seeds had germinated altogether.
The woodcock (Scolopax rusticola) belonged to the Grallae or Grallatores, an order of birds that included all the waders. It now belongs to the order Charadriiformes, which includes gulls and shorebirds. Herbert George Henry Norman sent CD the foot of a woodcock with some earth attached, from which seeds of Juncus bufonius (toadrush) were germinated (see Correspondence vol. 14, letter from H. G. H. Norman, 30 November 1866 and n. 2). CD added the information to Origin 5th ed., p. 440.
CD had long maintained that seeds might be dispersed over long distances by various means including being transported by birds, and predicted that other means of dispersal would be discovered (see Origin 4th ed., pp. 432–3; see also Correspondence vol. 14 for some of CD’s more recent discussions on dispersal). CD added the information on the seeds germinated from locust dung to Origin 5th ed., p. 439.
Lyell’s letter has not been found, but CD had puzzled over the means of distribution of land molluscs on oceanic islands for a long time (see Correspondence vol. 6, letter to P. H. Gosse, 28 September 1856 and n. 4). In Origin 4th ed., pp. 471–2, CD added information on recent experiments confirming his view that hibernating land molluscs could resist immersion in sea-water.
CD had been unable to obtain the eggs of land molluscs to test their resistance to sea-water (see Correspondence vol. 6, letter to W. D. Fox, 3 October [1856]).
According to CD’s ‘Journal’ (see Correspondence vol. 15, Appendix II), CD went to London on 28 November 1867. The reference is to Mary Elizabeth Lyell.
Lyell added the information about seeds in locust dung and in mud on the foot of a woodcock to the tenth edition of Principles of geology (C. Lyell 1867–8, 2: 420–1), but did not refer to CD’s information in his discussion of the distribution of land shells (ibid., pp. 421–32). Erasmus Alvey Darwin lived at 6 Queen Anne Street, London.

## Bibliography

Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 29 vols to date. Cambridge: Cambridge University Press. 1985–.

Lyell, Charles. 1867–8. Principles of geology or the modern changes of the earth and its inhabitants considered as illustrative of geology. 10th edition. 2 vols. London: John Murray.

Origin 4th ed.: On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. 4th edition, with additions and corrections. By Charles Darwin. London: John Murray. 1866.

Origin 5th ed.: On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. 5th edition, with additions and corrections. By Charles Darwin. London: John Murray. 1869.

## Summary

Describes seeds transported in locust dung. Discusses other cases of transport and migration.

## Letter details

Letter no.
DCP-LETT-5659
From
Charles Robert Darwin
To
Charles Lyell, 1st baronet
Sent from
Down
Source of text
American Philosophical Society (Mss.B.D25.336)
Physical description
LS(A) 4pp