TABLE OF CONTENTS. 



ARTICLE V. PALiEONTOLOGY OF THE IJPPER MISSOURI: A REPORT UPON COLLECTIONS MADE 

 PRINCIPALLY BY THE EXPEDITIONS UNDER COMMAND OF LlEUT. G. K. WaR- 



REN, U. S. Top. Engrs., in 1855 and 1856. Invertebrates. By F. B 

 Meek and F. V. IIayden, M. D. Part I. Pp. 158, and five Plates 

 (Published April, 1865.) 

 Introductory Remarks 

 I. Silurian Age. Potsdam Period 

 II. Carboniferous Age. Carboniferous Period 

 III. Carboniferous Age. Permian Period 

 lY. Reptilian Age. Jurassic Period 



Inde.^ .... 



Explanations of Plates. 



Vll 



1 



11 



48 



66 



129 



ARTICLE VI. Cretaceous Reptiles of the United States. By Joseph Leidy, M. D., 

 Professor of Anatomy in the University of Pennsylvania, Curator of the 

 Academy of Natural Sciences of Philadelphia. Pp. 140 and twenty plates. 

 (Published May, 1865.) 

 Introduction ........ 1 



Sauria ......... 5 



Chelonia . . . . . . . . .104 



A Synopsis, in which an attempt is made to define more closely the Genera 



and Species of Reptiles whose remains are described in the preceding pages 115 

 Index ......... 121 



References to the Plates . . . . . . .123 



