Dear Sir

I venture to trouble you once again, in accordance with the very kind permission given in your former note.¹ Though I did not then at all anticipate that I sh^d. so soon have had occasion to take advantage of it.— It is quite likely that you may not be able to give me the desired information & it will depend on your having a collection of skins of Madeira Birds.— M^r. Wollaston insists very strongly on those insects which are common ⁠⟨⁠in⁠⟩⁠ Europe, being generally of ⁠⟨⁠a⁠⟩⁠ smaller size in Madeira²

This point interests me much, & reminds me that the few non-endemic B⁠⟨⁠irds⁠⟩⁠ of the Galapagos Arch. w⁠⟨⁠ere⁠⟩⁠ of a smaller size than the same species elswhere. Have you any reason to think that this is so, even in ⁠⟨⁠a⁠⟩⁠ slight degree, at Madeira⁠⟨⁠?⁠⟩⁠ I have looked to your paper & to an abstract which I made of your Book, but cannot find any remark on this head;³ so that in all probability my question is superfluous, but yet I have thought that you would excuse me making it.—

Secondly, M^r Wollaston quotes on M^r Gould’s authority that certain races of Swallows, which migrate viâ Malta have certainly rather shorter wings, than have the same species which migrate by a longer route.—⁴ I think it would be an interesting point, if you have the means, carefully to compare the length of wing of the non-migratory swallows of Madeira with the skins of the same species from Europe.—

Lastly I am taking great trouble in collecting skins (& live birds) of all the many domestic varieties of Columba livia from all parts of the world: and I have written to a M^r. Mason, a professional collector now at Madeira to collect skins of the rock Pigeons for me; but I suspect that he is so little of an ornithologist, that he will collect for me perhaps only the other species.⁵ I see that you mention the C. livia, & a darker variety, as found at Madeira.⁶ Have you skins of these? & if I fail in getting specimens through M^r. Mason, would you have the great kindness to let me sometime look at your specimens?

I fear that you will repent of your kindness, & think that you have got a very troublesome correspondent. | I beg to remain | Dear Sir | Your obliged servant | Charles Darwin