From Arthur Edward Knox [c. March 1855–7?]1
at an early hour, & I have often witnessed the arrival of birds from the south—2 I hope to be able to do something in this way next month. The contents of the stomachs of graminivorous birds shot in the act of arriving should be preserved (I apprehend by washing them in water and keeping the seeds, if any). These should be forwarded to you I believe without delay? If you have time perhaps you can let me soon have a line to refresh my memory on this point—
Your hint about waterfowl3 may perhaps serve as a clew to unravel a mystery which puzzled me when I was a boy.4 At any rate it strengthens me in the opinion I then formed on the subject. The wild mountainous district in the Western portions of the Counties of Galway & Mayo in Ireland are studded with numerous loughs some very large, & others of smaller size and at various elevations above the level of the sea. At the beginning of the present century I believe there were no pike in any of these waters— The genus salmo in all its varieties lorded it over the lesser tenants of the deep— Into one of the lakes, pike were introduced, (by a short sighted proprietor) where of course they rapidly increased— These “freshwater sharks” a few years afterwards appeared in a distant lough which had no connection by any stream with the former—in fact was at the other side of a ridge of mountains. The pike were at first very small. How did they get there? I always fancied that the cormorants which used to come up from the sea to fish on the lough & used occasionally to visit the lesser ponds & even distant mountain pools, had a hand, or rather a foot, in it. Besides the pike-spawn which might have adhered to their legs and palmated toes, these birds, which have enormous gullets, might easily disgorge the contents of their first stomach on finding more acceptable prey than what it already contained—
I fear that I have tired your patience, but like all enthusiasts I am apt to override my hobby— Ever my dear Sir yrs very faithfully | A. E. Knox
CD annotations
Footnotes
Bibliography
Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 29 vols to date. Cambridge: Cambridge University Press. 1985–.
Knox, Arthur Edward. 1849. Ornithological rambles in Sussex; with a systematic catalogue of the birds of that county, and remarks on their local distribution. London.
Modern English biography: Modern English biography, containing many thousand concise memoirs of persons who have died since the year 1850. By Frederick Boase. 3 vols. and supplement (3 vols.). Truro, Cornwall: the author. 1892–1921.
Natural selection: Charles Darwin’s Natural selection: being the second part of his big species book written from 1856 to 1858. Edited by R. C. Stauffer. Cambridge: Cambridge University Press. 1975.
Origin: On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. By Charles Darwin. London: John Murray. 1859.
Summary
CD has suggested an explanation of how pike were introduced to a remote lake in Ireland by cormorants [carrying pike spawn on their feet or in their gullets].
Letter details
- Letter no.
- DCP-LETT-1624
- From
- Arthur Edward Knox
- To
- Charles Robert Darwin
- Sent from
- unstated
- Source of text
- DAR 205.2: 243
- Physical description
- ALS 2pp inc †
Please cite as
Darwin Correspondence Project, “Letter no. 1624,” accessed on 1 October 2023, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-1624.xml
Also published in The Correspondence of Charles Darwin, vol. 5