THE YEAR'S VERTEBRATE PALEONTOLOGY 503 



between that epoch and the Miocene. A similar service has 

 been accomplished by Mr. F. Roman {Comm. Geo/. Portugal, 

 1907) in regard to the mammalian fauna of the later Tertiary 

 strata on the right bank of the lower part of the Tagus valley. 

 In addition to remains of Mastodon, Hippariou, etc., the author 

 has described those of an apparently new species of rhinoceros, 

 Notices of later Tertiary mammals from Hungary will be found 

 in a paper by Mr. W. Gull, and others, published in the 

 Mitteilungen Ungar. geol. Anstalt, vol. xiv. p. 283. Similar brief 

 mention will suffice for a paper by Mr. A. Zdarsky on the 

 Tertiary mammal fauna of Eibiswald, published in the Jahrbuch 

 of the Austrian Geological Survey (vol. lvii. p. 437). 



A work of an altogether unique type is Mr. Charles Deperet's 

 Les Transformations dn Monde Animal (Paris, 1907). Its main 

 object is to discuss our present knowledge of the laws regu- 

 lating the modifications of animals, from the date of the first 

 appearance of life on the globe to the present day. After a 

 preliminary review of the rise of modern ideas with regard 

 to evolution, the author discusses the variability of species 

 in space and time, the constituent elements of phylogenetic 

 " trees," the causes of the extinction of species, the formation 

 of new types, and, finally, the important role played by migration 

 in the evolution of faunas. 



During the year the vertebrate fossils of the Fayum district 

 of Egypt have attracted American collectors ; and to the October 

 number of The Century Magazine Prof. H. F. Osborn contributes 

 an illustrated article describing his experiences while in search 

 of such remains, with remarks on the nature and origin of the 

 fauna and their bearing on the geographical distribution of 

 mammals. Among the illustrations, attention may be directed 

 to restorations of Arsinoithcrium, Hyeeuodon, and Zeuglodon. 

 In Eocene times the Fayum, in the author's opinion, was a 

 savanna-country, partly open, partly covered with scrub, and 

 partly with forest ; the temperature being much the same as 

 at the present day. That Africa (then much less extended to 

 the north than at the present day) was the home of the 

 ancestral proboscideans, sea-cows, hyraxes, and probably 

 hyaenodonts, Prof. Osborn is convinced ; but the absence in 

 the Eocene deposits of remains of primitive hippopotamuses, 

 ruminants, horses, and rhinoceroses, leads to the further 

 inference that " none of these quadrupeds had as yet reached 



