From John Gwyn Jeffreys 7 September 1851
7th. Septr. 1851
My dear Sir,
I have to return you my thanks for your obliging letter of the 31st ult.1 which I received on my return home.
It will give me much pleasure if the notes & specimens of Cirripedia, which I sent you are of any use to you in the preparation of your work2 which is not only much needed but will by all accounts be far superior to any which has yet been published on the subject both as respects the soft parts and metamorphoses of these interesting creatures as also their shells or calcareo-crustaceous coverings. The notes are entirely at your service as I shall not want them The specimens may be sent to Messrs. Holme & Co.3 No 10 New Inn when you have quite done with them—
I will now endeavour to answer your queries seriatim
1st. I send you a more readable & intelligible label as to what I consider the Balanus Balanoides of Risso.4 The specimens which I sent you form part of Mr. Wm. Clark’s collection,5 mixed with specimens of the Bal. crenatus6 and marked “Exmouth”. I never found the kind myself and I do not think it ought to be introduced as British on such meagre authority.
2nd. The B. Spongicola7 were dredged in the coralline zone at Exmouth on triassic sandstone I have it from the same place on Pecten opercularis as well as from Plymouth: you are welcome to one of my specimens.
3rd. The small Balanus which you name B. Improvisus8 on Rostellaria Pes Pelicani as well as those on Pecten Niveus were dredged by me in about 20 fathoms water in Loch Shieldaig—Rossshire—
5 I have taken B. Sulcatus9 at Exmouth & Plymouth, and believe it to be common to all our coasts.
I agree with you as to the inconvenience of burdening your work with synonymes & the extreme difficulty of making them out but as it will give a fresh starting point I think Naturalists might expect the Synonyms to be elucidated and given although not repeated ie. not to give every synonym in every hitherto published work but only those which are distinct. This however will be left to your better judgment.10
Believe me to remain dear Sir | Yours sincerely | J. G. J. Charles Darwin Esqe. | Down | Farnborough
P.S. I shall feel obliged by your labelling my specimens with the name you intend to adopt or use, if it does not give you too much trouble—
Has sent CD some cirripedes and notes which he hopes will be of use. Gives details of occurrence and source of some of the specimens.