120 PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY 



Page 

 55ession of Tuesday, January 1 130 



Some observations on the osteology of Diplodocus; by William J. 

 Holland 130 



Critical study of fossil leaves from the Dakota sandstone [ab- 

 stract] ; by E. M. Gress 131 



Observations on the skeleton of Moropus cooM in the American 

 Museum [abstract] ; by Henry Fairfield Osborn 131 



A long- jawed mastodon skeleton from South Dakota and phylog- 



eny of the Proboscidea ; by Henry Fairfield Osborn 133 



Continuation of symposium 138 



Mesozoic history of Central America and the West Indies; by 

 T. W. Stanton 138 



Cenozoic history of Central America and the West Indies ; by 

 T. W. Vaughan 138 



Relationships of the Mesozoic reptiles of North and South Amer- 

 ica ; by S. W. Williston 138 



Affinities and origin of the Antillean mammals ; by W. D. Matthew 138 



Fresh-water fish faunas of North and South America; by C. H. 

 Eigenmann 138 



Evidence of recent changes of level in Porto Rico, as shown by 



studies in the Ponce district ; by Graham John Mitchell 138 



Presentation of papers 141 



Generic nomenclature of the Proboscidea [abstract] ; by W. D. 



Matthew 141 



Session of Wednesday, January 2 141 



Report of the Auditing Committee 141 



Presentation of papers 142 



Cretaceous overlaps in northwest Europe and their bearing on the 

 bathymetric distribution of the Cretaceous Silicispongise [ab- 

 stract] ; by Marjorie O'Connell 142 



New bathymetrical map of the West Indies region [abstract] ; by 

 Chester A. Reeds 142 



Isolation as a factor in the development of Paleozoic faunas [ab- 

 stract] ; by Amadeus W. Grabau 148 



An Ordovician fauna from southeastern Alaska [abstract] ; by 

 Edwin Kirk 143 



Affinities and phylogeny of the extinct Camelidse [abstract] ; by 

 W. D. Matthew 144 



Rocky Mountains section in the vicinity of Whitemans Pass [ab- 

 stract] ; by C. W. Drysdale and L. D. Burling 145 



Further light on the earlier stratigraphy of the Canadian Cor- 

 dillera [abstract] ; by Lancaster D. Burling 145 



Evolution of vertebrae ; by S. W. Williston 146 



Diseases of the Mosasaurs [abstract] ; by Roy L. Moodie 147 



Report on a collection of Oligocene plant fossils from Montana 

 [abstract] ; by O. E. Jennings 147 



New Tillodont skull from the Huerfano Basin, Colorado [ab- 

 stract] ; by Walter Granger 147 



