956 PRINCIPLES OF STRATIGRAPHY 



phins, etc., are aquatic (mostly marine) mammals, and occur as far 

 back as the Miocenic. Squalodon and Zeuglodon are fossil repre- 

 sentatives. The Sirenia are herbivorous aquatic mammals repre- 

 sented by the living manatee and dugongs, and the recently extinct 

 sea-cow (Rhytina), etc. The Ungulates, or hoofed mammals, com- 

 prise: (i) the Eocenic Amblypoda (Coryphodon. Tinoceras, etc.), 

 large, heavy creatures; (2) the Prohoscidea, or elephants (Dino- 

 therium. Mastodon. Stegodon, Elephas, etc.) ; (3) the Condilarthra 

 (Phenacodus) ; (4) the Perissodactyla, or unevenly-toed ungulates 

 (Tapir, Rhinoceros. Titanothere, and the horse family) ; (5) the 

 Artiodactyla, or even-toed ungulates, divided into the Bunodontia 

 (pigs, hippopotamus, Anthracotherium, etc.) ; and Sclenodontia, 

 (Oreodon [Tertiary], camels, deer, etc.; giraffes, antelopes, goats, 

 sheep, cattle, etc.) ; (6) Toxodontia — Tertiary forms, including 

 Toxodon. Typotherium, etc. 



The final order of the mammals is that of the primates, which 

 includes Quadrumana (apes, monkeys, etc.), and the Bimana, or 

 man. 



BIBLIOGRAPHY XXIV. 



(Text-books of Palaeontology, etc.) 



BERNARD, FfiLIX. 1895. Elements de Pal^ontologie. Bailliere et 



Fils, Paris. 

 GRABAU, A. W., and vSHIMER, H. W. 1909-1910. North American 



Index Fossils. 2 vols. A. G. Seiler and Company, New York. 

 GURICH, GEORG. 1908-09. Leitfossilien. 2 parts. Gebriider Born- 



traeger, Berlin. 

 KOKEN, ERNEvST. 1896. Die Leitfossilien. Hermann Tauchnitz, 



Leipzig. 

 NICHOLSON, ALLEYNE, and LYDEKKER, RICHARD. 1889. A 



Manual of Palaeontology. 2 vols. W. Blackwood and Sons, Edinburgh 



and London. 

 OSBORN, HENRY F. 1910. The Age of Mammals. Macmillan Com- 

 pany, New York. 

 STEINMANN, GUSTAV. 1903. Einfiihrung in die Palaeontologie. 



Wilhelm Engelmann, Leipzig. 2nd edition, 1907. 

 STROMER, ERNST. 1909,1912. Lehrbuch der Palaeozoologie. 2 parts. 

 ZITTEL, KARLA. VON. 1881-85. Handbuch der Palaeontologie. French 



translation, Traite de Paleontologie, by Charles Barrois, Paris. 

 ZITTEL, K. A. VON. 1895. Grundziige der Palaeontologie . 2nd Edi- 

 tion, 1910-11. 2 vols. Munich. 

 ZITTEL, K. A., VON. 1900. Text-book of Palaeontology. Translated by 



Charles R. Eastman with collaboration by many specialists. 2 vols. 



Macmillan Company, New York. 



(Classification, etc.) 

 ALLEN, J. A. 1906. The "EHmination" and "First Species" Methods of 



Fixing the Types of Genera. Science, N. S., Vol. XXIV, pp. 773-779. 



