To W. E. Darwin 4 February [1881]
Down, | Beckenham, Kent. | (Railway Station | Orpington. S.E.R.)
Feb. 4th
My dear W.
Many thanks. Do not trouble about Acacia, as yours seems a bad place, & Frank has just collected almost 60 at Mr Teesdale’s place: they also prove ill-adapted for my purpose, as I cannot decide positively, whether basal end, when drawn in, has been gnawed.1 The little leaves sent, were so crumpled, partly from drying that I could make out nothing, & I have got a good body of facts showing that as a general rule leaves are drawn by their apices. Therefore the case of your rhododendron leaves interested me, as 7 were drawn in by base & 2 by apex. The case is all the better in relation to intelligence that the plant is not a native.2 Like a big ass I thought at first that these leaves had been rolled up by the worms, & placed them in water, so that they have expanded somewhat. On reflexion I was almost convinced that they are first rolled up from drying & are afterwards dragged into holes. I find that the shape of the fresh leaves here differs considerably in the different vars., being sometimes much narrower near the base than near apex. I also found many dead leaves somewhat curled up, & I think that in this state their basal end is generally narrower than their apical end, & this wd account for their being generally drawn in by base.
Now will you endeavour to find a good many more drawn-in leaves, & count how many are drawn in by base & how many by apex.— Also look to shape of fresh leaves of neighbouring bushes, & more especially to dead withered leaves & observe whether the curling in is more at base than apex, so that it is best for the worm to drag them in by base.—
I can find as yet here none dragged in.—
I have collected many dead leaves & shall look at them tomorrow & collect still more. But you will see that as the vars. differ I dare not trust to my observations here for the leaves, (perhaps of other vars.) drawn in near you.—
The interest is that worms should apparently be able by touch of ant. end3 of body to judge of shape, so as to draw in objects in the most favourable manner.—
I am now trying triangles of card of this shape,— only 3 as yet have been drawn in & all 3 by apex.—4
We heard from George this morning just arrived at Madeira after rather stormy passage.—5
Yours affect. | C. Darwin
Footnotes
Bibliography
Darwin, Francis. 1916. Memoir of Sir George Darwin. In Scientific papers, by George Howard Darwin. Vol. 5. Cambridge: Cambridge University Press.
Earthworms: The formation of vegetable mould through the action of worms: with observations on their habits. By Charles Darwin. London: John Murray. 1881.
Summary
Discusses earthworms and their ability to perceive narrowest points of leaves to draw them into their burrows.
Letter details
- Letter no.
- DCP-LETT-13036
- From
- Charles Robert Darwin
- To
- William Erasmus Darwin
- Sent from
- Down
- Postmark
- FE 4 81
- Source of text
- DAR 210.6: 174
- Physical description
- ALS 6pp & cov
Please cite as
Darwin Correspondence Project, “Letter no. 13036,” accessed on 30 May 2024, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-13036.xml