My dear Sir,

I have received a wonderful nest from the R. Uraguay in S. America.² It is a wonderful structure appearing to be made of horse hair but really of some vegetable fibre. The bird is called “El boyero” & is said to be black or almost so, & about the size of our black-bird.³ No doubt Azara describes so wonderful a nest.⁴ I write all this because if you would like to present it to the British Museum, I will send it to you. I may just add that the bird is said often to perch on the back of cattle & horses & the sender supposes the material is horse-hair

My dear Sir | Yours sincerely | Ch. Darwin