Darwin's publications--his letter to "Nature" on the "Dispersal of Freshwater Bivalves," April 6th, 1882.)
Down, February 21st, 1882.
Your fact is an interesting one, and I am very much obliged to you for communicating it to me. You speak a little doubtfully about the name of the shell, and it would be indispensable to have this ascertained with certainty. Do you know any good conchologist in Northampton who could name it? If so I should be obliged if you would inform me of the result.
Also the length and breadth of the shell, and how much of leg (which leg?) of the Dytiscus [a large water-beetle] has been caught. If you cannot get the shell named I could take it to the British Museum when I next go to London; but this probably will not occur for about six weeks, and you may object to lend the specimen for so long a time.
I am inclined to think that the case would be worth communicating to "Nature."
P.S.--I suppose that the animal in the shell must have been alive when the Dytiscus was captured, otherwise the adductor muscle of the shell would have relaxed and the shell dropped off.
LETTER 401. TO W.D. CRICK. Down, February 25th, 1882.
I am much obliged for your clear and distinct answers to my questions. I am sorry to trouble you, but there is one point which I do not fully understand. Did the shell remain attached to the beetle's leg from the 18th to the 23rd, and was the beetle kept during this time in the air?
Do I understand rightly that after the shell had dropped off, both being in water, that the beetle's antenna was again temporarily caught by the shell?
I presume that I may keep the specimen till I go to London, which will be about the middle of next month.
I have placed the shell in fresh-water, to see if the valve will open, and whether it is still alive, for this seems to me a very interesting point. As the wretched beetle was still feebly alive, I have put it in a bottle with chopped laurel leaves, that it may die an easy and quicker death. I hope that I shall meet with your approval in doing so.
One of my sons tells me that on the coast of N. Wales the bare fishing hooks often bring up young mussels which have seized hold of the points; but I must make further enquiries on this head.
LETTER 402. TO W.D. CRICK. Down, March 23rd, 1882.
I have had a most unfortunate and extraordinary accident with your shell. I sent it by post in a strong box to Mr. Gwyn Jeffreys to be named, and heard two days afterwards that he had started for Italy. I then wrote to the servant in charge of his house to open the parcel (within which was a cover stamped and directed to myself) and return it to me. This servant, I suppose, opened the box and dropped the glass tube on a stone floor, and perhaps put his foot on it, for the tube and shell were broken into quite small fragments. These were returned to me with no explanation, the box being quite uninjured. I suppose you would not care for the fragments to be returned or the Dytiscus; but if you wish for them they shall be returned. I am very sorry, but it has not been my fault.
It seems to me almost useless to send the fragments of the shell to the British Museum to be named, more especially as the umbo has been lost. It is many years since I have looked at a fresh-water shell, but I should have said that the shell was Cyclas cornea. (402/1. It was Cyclas cornea.) Is Sphaenium corneum a synonym of Cyclas? Perhaps you could tell by looking to Mr. G. Jeffreys' book. If so, may we venture to call it so, or shall I put an (?) to the name?
As soon as I hear from you I will send my letter to "Nature." Do you take in "Nature," or shall I send you a copy?
I. Descent of Man.--II. Sexual Selection.--III. Expression of the Emotions.
2.VIII.I. DESCENT OF MAN, 1860-1882.
LETTER 403. TO C. LYELL. Down, April 27th .
I cannot explain why, but to me it would be an infinite satisfaction to believe that mankind will progress to such a pitch that we should [look] back at [ourselves] as mere Barbarians.