216 TEN YEARS^ PROGRESS IN VERTEBRATE PALEONTOLOGY 



1906 



Andrews (44) in a large volume published, among other things, final 

 descriptions and figures of nine turtles from the Fayum of Egypt. Two 

 of these had not been previously reported. Hay (27) described and fig- 

 ured Xenochelys formosa and Terrapene putnami and proposed the new 

 genus Eclimatemys; also (27) gave the characters which distinguish 

 Chisternon from Baena, and described more fully Anosteira. In another 

 paper (15) he made known five new Miocene species and described a skull 

 of Stylemys nebr ascends, all from materials in Carnegie Musieum. 

 Lambe (32) described Testudo exornata from the Oligocene of Canada 

 and Baena pulchra from the Belly Eiver beds. Later (32) he placed 

 the latter species in the new genus Boremys and furnished notes on 

 several other species. Eiggs (31) described and figured the new species 

 Basehmys sinuosa. Wieland (15) discussed the plastron of Protostega, 

 Later (33) he described at length the osteology of Protostega, giving 

 special attention to the limbs. He placed the genus in the Cheloniidae. 



1907 



Hay (27) described and illustrated seven new species of turtles from 

 the Tertiary of the United States, the most important being, perhaps, a 

 species of Macrochelys from the Pliocene or Pleistocene of Florida and 

 a nearly complete skeleton of a trionychid from the Torre j on of Xew 

 Mexico, Aspideretes singularis. Jaekel (47) published a final thesis on 

 P/acoc7?e/?/s, containing 90 pages, 10 plates, and 50 text figures. To him 

 there appeared to be unmistakable relationships between the turtles and 

 the Placodonts ; that both were to be traced back to a common ancestor; 

 and that, especially, the original condition of the turtle shell becomes 

 intelligible through the homologous structures of PJacochelys. 



1908 



Hay (34) published his monograph, "The Fossil Turtles of North 

 America.^' This is a quarto of 568 pages, with 113 plates and 704 text 

 figures. It purports to describe all the species known at the date of 

 publication. The author divided the order into the suborders AthecaB 

 and Thecophora; the latter with the superfamilies Amphichelydia, 

 Pleurodira, Cryptodira, and Trionychoidea. He was inclined to derive 

 the turtles from the Cotylosauria, and more especially the Otocoelidae. 

 After this was issued another paper was published (35), in which five 

 new species from various levels were described and illustrated; there 

 was also a note on Glyptops plicatulus. Moodie (39) declared that the 



