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Darwin Correspondence Project

From John Scott   22 March 1872

Royal Botanic Gardens [Calcutta]

22 March 1872

Dear Sir,

I have delayed writing in the hope that I might add to my own scraps of information on the habits of worms that from friends which I have written to in the hills and Central India. I fancy however from their silence as yet that they have nothing to tell me of those just now and this I can understand if they are as inactive on the surface there as here. I shall thus delay no longer in sending my own moiety.—1

Worms are indeed abundant everywhere here: in the jungles (dry and grass clad) lawns & rice fields (when the rains are over they could not live in them I fancy during the growing season when all is covered with water. As regards our lawns I indeed am mistaken if they are not even more troublesome than they are in Britain. At the close of the rains they are most inactive: the finest of our lawns is then only kept in anything like order by almost daily rolling. If left to work undisturbed then for a very few days they would have it studded with large castings: their activity has often surprised me. I can give you no exact information as to how the castings disappear, as they annually and naturally do: but I shall be careful to afford you it when the time comes round again for making the observations. This I know however that the casts do attain a considerable size on unrolled grassy surfaces during the early part of the cold season when the upper soil is moist and easily bored in by them: these as a rule remain nearly intact until the following rainy season, when you find them gradually disappearing and unless the soil is of a very tenacious character all becomes again fairly well levelled down by the end of the rains, when the operation of up casting is resumed. I cannot tell you the worms fend in the low rice lands during the rains, the soil being always less or more submerged. Still when the crops are cut and the surface clear of water, then do you again find worms at work.

In the gardens here you then see them on the surface amongst the grass and their paths. I have never observed them making fresh castings there; but I shall see to this as the rains return. Any work they could do of this sort then would be quickly levelled I think.— In the cold season we do not as a rule find the worms boring much under the surface: I do not think much beyond ten inches or a foot. In the hot season they go deeper. I cannot actually say how much; I have heard of them boring down to about four feet; but I have never actually seen them more than 212 feet: at 2 feet they are not infrequent.2 In this season you will rarely observe any fresh castings in any open lawns: in dense woods or any shady and moist place you may find a few; but anywhere they then lay and seemingly pass the hot season in a quasi dormant state.

The period for active work is thus with the rainy and hot seasons confined to little over two months annually, but really during that time the alteration they effect in the surface of our lawns &c, is by no means trifling, and as I have said (and as I think subsequent observations will prove) greater than on parity at home.

It will I assure you be a very great pleasure to me to work up this matter in the coming rainy and cold seasons, and I only beg that you will tell me of any observations that you wish made and that I may be competent to and it shall not be a lack of time which will interfere with my making them.

You asked in one of your letters lately about the Leersia,3 I had seeds of this from you in

CD annotations

2.1 abundant everywhere] underl red crayon
2.1 jungles] underl red crayon
2.5 the finest … castings: 2.7] scored red crayon
2.10 the casts … size 2.11] underl red crayon
2.15 by … operation] underl red crayon
2.17 crops are cut] underl red crayon
2.18 clear of water,] underl red crayon
3.4 cold … deeper. 3.6] scored red crayon
3.9 find a few;] underl red crayon
3.10 hot] underl red crayon
3.10 quasi dormant] underl red crayon
4.1 rainy … annually, 4.2] underl red crayon
4.4 greater … home] underl red crayon
6.1 You … in 6.2] crossed ink

Footnotes

CD had asked Scott for observations on wormcastings in his letter of 15 January 1872.
CD cited Scott for his information on the depth of worm burrows in Earthworms, pp. 125–6.
In a letter to Scott of 3 June 1868 (Correspondence vol. 16), CD had asked whether Leersia produced perfect (that is, open or non-cleistogamic) flowers in India.

Summary

Describes habits of worms.

Discusses Leersia experiments.

Letter details

Letter no.
DCP-LETT-8249
From
John Scott
To
Charles Robert Darwin
Sent from
R. Bot. Gard., Calcutta
Source of text
DAR 177: 120
Physical description

Please cite as

Darwin Correspondence Project, “Letter no. 8249,” accessed on 19 February 2019, http://www.darwinproject.ac.uk/DCP-LETT-8249

Also published in The Correspondence of Charles Darwin, vol. 20

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