To Charles Lyell   30 July 1837

I believe there are 27 land birds from the Galapagos, all new except one, (a species of very wide range) yet all of an American form, some north, some south, Now as the Galapos is on the Equator is not this curious— Reptiles the same— Has your late work at shells startled you about the existence of species?¹ I have been attending a very little to species of birds, & the passages of forms, do appear frightful—every thing is arbitrary;² no two naturalists agree on any fundamental idea that I can see. I had a most interesting morning with Owen (who is gone to rest for a month in the N. of England) at the Coll. of Surgeons—³ We made out the rem^s. of 11 or 12 great animals, besides these some rodents, one of wh. is a distinct species, but most strictly S. American genus. At Bahia Blanca there were no less than five great Edentatas! what could these monsters have fed upon— I am well convinced like the present Armadillos they lived on land nearly desert— I have worked out the non relation of bulk of animals & luxuriance of vegetation, & I have been perfectly astonished at some of the facts given me by D^r. Smith.⁴ If it would be any satisfaction to you I think it could be proved rhinoceroses live upon air, certain it is they must be light feeders. What will you say to the tusk of a boar like the African species being imbedded with the Edentata. Lastly I am sure when you read my evidence (& see the tooth) you will be as much convinced as I am that a horse was formerly common on the Pampas as at the present day.⁵ What an extraordin^y. mystery it is, the cause of the death of these numerous animals, so recently, & with so little physical change.—⁶