IV.—Note on a Model of the Skull and Mandible of Prozeuglodon atrox, Andrews

Extract

During the last few years several papers have been published which throw much light on the early history of the whales, a matter about which there have been great doubt and difference of opinion. Two important points appear to have been settled: first, that the Zeuglodonts (Archœceti) are descended from the primitive group of land-carnivores, usually known as the Creodonta, and, second, that the Toothed-whales (Odontoceti) are really derived from the Zeuglodonts. On this second point there may still be room for doubt, although in the opinion of the present writer the evidence brought forward by Professor Abel in several papers, is at least sufficient to demonstrate the extreme probability that the Archæoceti are really ancestors of the Odontoceti. The origin of the Baleen-whales (Mystacoceti) is still obscure, but the fact that numerous true teeth are found in the unborn young, points to the probability that these animals also may have originated from the same, or a closely related stock as that from which the Odontoceti have descended.