To F. B. Goodacre   13 August [1879]¹

Dear Sir

I am much obliged for your note. With respect to my own success, it has only been moderate, but has sufficed to shew that the hybrids are fertile inter se.² I was not aware that geese will not copulate except on the water, & I kept the birds enclosed in a large wire enclosure.— As soon as I discovered about the copulation, I sent them to a pond, & afterwards reared 2 young birds, one of which unfortunately killed itself. In a second hatch I reared 3 fine young Birds—so that I now have 4 young birds.— I found it quite necessary to keep my birds enclosed, as they w^d wander off to a pond quarter of a mile distant where there were other geeses; but this was discovered before the breeding season.

I shall return home in 2 or 3 weeks & sh^d. be glad to hear whether you would like to have all the geese returned to you, as under the circumstances just stated, it is too troublesome to keep them any longer. What had I better do with respect to D^r. Meadows?³ is it possible to distinguish males & females whilst the birds are young? Shall I send him the two old Birds?

I sh^d. like to publish a notice of a few lines in length in the Proc. Zoolog. Soc. on the fertility of the hybrids; & if so may I use your results?⁴ With respect to the windpipe I think that Yarrell gives figures; but I daresay I could find out when in London later in the autumn.—⁵

Thanking you very sincerely for all your kindness, I remain | Dear Sir | Yours faithfully | Ch. Darwin