138 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY 



MESOZOIC HISTORY OF CENTRAL AMERICA AND THE WEST INDIES 

 BY T. W. STAIS'TON 



Discussion of this paper was deferred until the last one of the series of 

 invertebrate paleontology was presented by the author, Doctor Vaughan. 



CENOZOIC HISTORY OF CENTRAL AMERICA AND THE WEST INDIES 



BY T. W. VAUGHAN 



A general review of the problems connected with the history offered 

 by invertebrate paleontology was brought out in the discussion of these 

 papers, which occurred at this point. Prominent among the speakers 

 were Messrs. Holland, Osborn, Yaughan, Merriam, Matthew, and Grabau. 



The evidence on this history offered by vertebrate paleontology was 

 given in the two following papers, discussion again being deferred: 



RELATIONSHIPS OF THE MESOZOIC REPTILES OF NORTH AND SOUTH 



AMERICA 



BY S. W. WILLISTON 



AFFINITIES AND ORIGIN OF THE ANTILLEAN MAMMALS 

 BY W. D. MATTHEW 



This portion of the symposium called forth still more discussion, in 

 which Messrs. Merriam, Matthew, Osborn, Eigenmann, Grabau, Willis- 

 ton, and Price participated. During this discussion. Doctor Eigenmann 

 was requested to give the evidence afforded by the fishes. His remarks 

 entitled as below were highly interesting and appreciated. 



FRESH-WATER FISH FAUNAS OF NORTH AND SOUTH AMERICA 

 BY C. H. EIGEXilAXN 



In this discussion Doctor Grabau mentioned the work and results of 

 Graham J. Mitchell on recent changes of level in Porto Eico. 



EVIDENCE OF RECENT CHANGES OF LEVEL IN PORTO RICO, AS SHOWN BY 

 STUDIES IN THE PONCE DISTRICT^ 



BY GRAHAM JOHN MITCHELL^ 



(Abstract) 



With the inauguration of the Natural History Survey of Porto Rico, under 

 the joint auspices of the New York Academy of Sciences and the Insular Gov- 



1 By permission of the Porto Rico Committee of the New York Academy of Sciences. 

 Report on the geology of the Ponce district in preparation, 

 - Introduced by A. W. Grabau. 



