Page:Popular Science Monthly Volume 41.djvu/842

822 preliminary descriptions, must have stood near the source from which both ungulates and rodents have taken their origin.

Very many interesting Edentata and rodents have been met with in the same beds, but it is the marsupial group which surpasses all others in interest. One carnivorous animal of this group (Prothylacinus) is almost identical with the now existing pouched wolf (Thylacine) of Tasmania; while another fossil genus (Protoproviverra) is quite akin to the most characteristic carnivorous marsupial, the Tasmanian Devil. Although F. Ameghino's descriptions are not yet complete, the best authorities on this subject in this country and Germany do not hesitate to recognize a purely Australian type in these South American forms, which, on the other side, can safely be connected with the group of primitive carnivors (Hyænodon, Pterodon, etc.) which appeared at a later epoch in Europe. Moreover, the same beds contain fossil remains of primates (Homunculus, Anthropops, Homocentrus, Eudiastatus) which seem to represent ancestors of all the subsequent apes, but stand also in connection with the lemurs, and also with the ungulates, or, rather, with their Toxodon ancestors. They seem to represent the most ancient primates known, and indicate that the first representatives of the whole group must be sought for as far back as the end of the Secondary period. Finally, we must mention the discovery of remains of man which are considered by F. Ameghino as belonging to the Pliocene and Miocene ages.

The "missing links" are coming, as we see, in such abundance that it will take several years before anatomists, in whose hands this rich material will now be put, have disentangled the numerous and striking affinities between so many different types which we have briefly enumerated. But geologists will also have a word to say about these discoveries, which raise again the very great question as to the long-since noticed affinities between the faunas of all southern continents and the presumed previous connection between those continents. Apart from all other considerations, the resemblance between the fossil marsupials of South America and the marsupials now living in Australia is so great that it is not possible to admit that forms so near to each other (and both so abnormal) might have developed independently upon two remote continents. It seems almost unavoidable to admit that some direct land connection has existed between South America and Australia, although all we know about the