PALEONTOLOGY. 361 



PALEONTOLOGY. 



Case, E. C, University of Michigan, Ann Arbor, Michigan. Study of the 

 vertebrate fauna and paleogeography of North America in the Permian 

 period, with especial reference to world relations. (For previous reports see 

 Year Books Nos. 2, 4, 8-17.) 



Since submitting the last report, Dr. Case has devoted his time to 

 the preparation of the manuscript of Publication No. 283, on the 

 "Environment of vertebrate life in the late Paleozoic of North Amer- 

 ica." Since the completion of this work he has begun the compilation 

 of material which, it is hoped, will show the environment in which the 

 vertebrate animals of other parts of the world developed during the 

 same period of time as is covered by this publication. In the summer 

 of 1919 Dr. Case spent several weeks studying the Permo-Triassic 

 boundary-Une in the southwestern part of the United States. 



Hay, Oliver P., U. S. National Museum, Washington, D. C. Associate in 

 Paleontology. (For previous reports see Year Books Nos. 11-17.) 



The greater part of the past year has been devoted to a study of the 

 Pleistocene vertebrates and to the Pleistocene geology of Quebec, 

 Ontario, the New England States, West Virginia, Ohio, Kentucky, 

 and Tennessee. The regions lying on each side of the St. Lawrence 

 River and lakes Ontario and Erie are covered by the deposits laid 

 down by the last ice sheet, the Wisconsin. In the loose deposits over- 

 lying the Wisconsin drift are buried remains of animals which survived 

 the last period of cold or which entered the country after this geologic 

 stage had ended. In comparison with that of the early Pleistocene 

 an impoverished fauna is indicated. For New York, the publications 

 of Dr. H. L. Fairchild were of great service to the present writer. As the 

 Wisconsin ice sheet retired, the water of the Great Lakes stood at suc- 

 cessively lower levels. In deposits made at nearly the present level of 

 these lakes in the region now reported on, as well as that along lakes 

 Huron and Michigan, have been found teeth and bones of mastodons, 

 two species of elephants, and extinct peccaries, proofs that these 

 animals existed there until only a few thousand years ago. 



In the limestones of the Alleghany region, from central Pennsyl- 

 vania to northern Alabama, are found numerous caves and fissures. 

 These have furnished and are still furnishing abundant remains of 

 vertebrated animals, mostly mammals. These belong principally to 

 extinct species, and appear to have existed during the middle or early 

 Pleistocene. Every effort ought to be made to preserve all such 

 remains, often met with accidentally. 



Some weeks have been devoted to the study and description of the 

 species of several small but valuable collections. Some of these, as 

 two from caves in Tennessee, one made at Alton, Illinois, and another 

 made at Afton, Oklahoma, have lain undescribed for many years. 

 They are furnishing much new and interesting information. Another 



