INTEODUCTION. xxv 



spread to their present habitats, the genus becoming extinct elsewhere, though it 

 persisted in Egypt till the Miocene. 



The Ophidia are represented by two genera only : one GigantopMs, a Python of very 

 large size, the other Pterosphenus, of which one species, F schweinfurthi, is found in 

 the Fayum, while another, P. schucherti, occurs in the Eocene of Alabama ; in both 

 localities remains of Zeuglodonts are abundant in the same beds, a circumstance which, 

 coupled with the peculiar structure of the vertebrae, shows that these Snakes were 

 aquatic and probably marine. Nevertheless, it does not seem likely that they would 

 cross oceans of great width, and their presence in Egypt and in Alabama seems to be 

 an argument in favour of the presence of a shore-line across what is now the Atlantic 

 Ocean, probably lying somewhat to the south. The presence of primitive Sirenians in 

 Egypt (Eotherium) and the West Indies [Prorastomus) is explicable on the same 

 grounds. 



No Amphibia have yet been found, and the Fishes are of no great interest, being all 

 either Elasmobranchs or Siluroids : among the former occur several types of Sawfish, 

 while the latter are chiefly remarkable for their great similarity to forms now living in 

 the Birket-el-Qurun and the Nile. 



From the above summary of the contents of this Catalogue, it will be seen that 

 a very considerable number of early Tertiary Vertebrates, especially Mammals, are 

 already known from Egypt, and that practically all of them have been discovered 

 since the beginning of 1900, so that, although Professor Osborn writing in that 

 year could say of Africa with truth, "It is the dark continent of Palaeontology, for 

 it has practically no fossil mammal history," this reproach is at least in a fair 

 way to be removed. At present, of course, the species known must be a mere 

 fraction of the faunas inhabiting the Ethiopian region during the Middle and 

 Upper Eocene periods, but the proportion of peculiar types included in them 

 is great enough -ttr~3how how fully justified the writers above referred to were in 

 their assumption that the Ethiopian continent in early Tertiary (and perhaps 

 pre-Tertiary) times was a very important centre of mammalian evolution. 



The question of the relations of this Ethiopian region to the rest of the world is one 

 of very great interest. The probability of a series of temporary land-connections 

 between it and the Palsearctic continent has already been referred to above and has 

 been fully discussed by Osborn, Stehlin, Tullberg, &c. ; in all cases so far as known 

 these connections occurred during the Tertiary period. Furthermore, the probability 

 of a former land-connection with South America has been argued with much force by 



