Artiodactyle

Finally, it appears that this very recently extinct beast presents a highly generalized type of structure, uniting in one organic form both artiodactyle and perissodactyle characters, and that in a manner not similarly found in any other known creature living, or fossil. ❋ St. George Mivart (N/A)

Others again inclined the balance of probability towards the artiodactyle. ❋ St. George Mivart (N/A)

At the same time the differentiation of artiodactyle and perissodactyle forms existed as long ago as in the period of the Eocene ungulata, and that in a marked degree, as has been before observed. ❋ St. George Mivart (N/A)

The former of these has the toes odd (perissodactyle), the other has them even (artiodactyle). ❋ St. George Mivart (N/A)

The mammalia, for example, were long thought to have first appeared in Tertiary times, where they are represented in some of the earlier deposits by all the great divisions of the class fully developed -- carnivora, rodents, insectivora, marsupials, and even the perissodactyle and artiodactyle divisions of the ungulata -- as clearly defined as at the present day. ❋ Alfred Russel Wallace (1868)