Evolution / by Patrick Geddes and J. Arthur Thomson.

  • Patrick Geddes
Date:
[1911?]
Catalogue details

Licence: Public Domain Mark

Credit: Evolution / by Patrick Geddes and J. Arthur Thomson. Source: Wellcome Collection.

    29/264 (page 25)
    One of them, Phenacodus, was called by its discoverer, Professor E. D. Cope, a “ five-toed horse,” but this is not to be taken too literally. 44 The first undoubted horse-like animal appearing in the rocks of North America is a little creature not more than eleven inches high, known to science as Eohippus. This interesting animal had already made a long stride in the direction of the modern horse, as the number of toes is now reduced to four in front and three behind, and the bones of the wrist and ankle have shifted so as to interlock, which greatly strengthens the foot.” It seems that Eohippus was also represented in Britain, and it is possible that migrants by way of Asia and what is now the Behring Strait started the American stock. Apparently more primi¬ tive than Eohippus is the 44 coney-like crea¬ ture ” Hyracotherium, but only the skull is known. 44 Commencing with the Hyraco¬ therium,” Dr. Matthew writes, 44 twelve stages have been recognized from as many successive formations, showing the gradual evolution of the race into its modern form; and each stage is characteristic of its particular geological horizon. Besides the main line of descent which led into the modern horses and zebras, there were several collateral branches which have left no descendants.”