And now I have done my jottings, and once again congratulate you on having
brought out so grand a work. I have been a little disappointed at the
review in "Nature." (392/4. June 22nd, 1876, pages 165 et seq.)


LETTER 393. A.R. WALLACE TO CHARLES DARWIN.
Rosehill, Dorking, July 23rd, 1876.

I should have replied sooner to your last kind and interesting letters, but
they reached me in the midst of my packing previous to removal here, and I
have only just now got my books and papers in a get-at-able state.

And first, many thanks for your close observation in detecting the two
absurd mistakes in the tabular headings.

As to the former greater distinction of the North and South American
faunas, I think I am right. The edentata being proved (as I hold) to have
been mere temporary migrants into North America in the post-Pliocene epoch,
form no part of its Tertiary fauna. Yet in South America they were so
enormously developed in the Pliocene epoch that we know, if there is any
such thing as evolution, etc., that strange ancestral forms must have
preceded them in Miocene times.

Mastodon, on the other hand, represented by one or two species only,
appears to have been a late immigrant into South America from the north.

The immense development of ungulates (in varied families, genera, and
species) in North America during the whole Tertiary epoch is, however, the
great feature which assimilates it to Europe, and contrasts it with South
America. True camels, hosts of hog-like animals, true rhinoceroses, and