592 RECORD OF MEETINGS OF THE 



SECTION OF BIOLOGY. 



April io, 1905. 



Section met at 8.15 p.m., Vice-President Wheeler presiding. 



The minutes of the last meeting of the Section were read and 

 approved. 



The following program was then offered : 

 H. F. Osborn, The Ideas and Terms of Modern Philosophical 



Anatomy. 

 0. P. Hay, The Turtles of the Bridger Basin. 



Summary of Papers. 



The abstract of Professor Osborn's paper will be published 

 under its own title in Science. 



Dr. Hay gave a brief description of the extent of the Bridger 

 beds and of the nature of the materials composing them. 

 He expressed the conviction that these deposits had not been 

 made in a lake, but . over the flood-grounds of rivers. The 

 region was probably covered with forests, and teemed with 

 animal life. In the streams were numerous turtles. Many 

 species of these have been described by Dr. Leidy and Professor 

 Cope. In the speaker's hands are materials for the description 

 of about a dozen more species. The American Museum party 

 of 1903 collected many specimens of the genus and these have 

 furnished good skulls, neck, shoulder, and pelvic girdles, and 

 the limbs. These materials confirm the validity of Lydekker's 

 group called Amphichelydia, and show that from it sprang 

 the modern superfamilies Cryptodira and Pleurodira. 



M. A. Bigelow, 



Secretary. 



SECTION OF ASTRONOMY, PHYSICS, AND CHEMISTRY. 

 April 17, 1905. 



Section met at 8.15 p.m., Vice-President von Nardroff pre- 

 siding. 



The minutes of the last meeting of the Section were read 

 and approved. 



The following program was then offered : 



