FAUNA AND FLORA 2l)U 



Having brought the charge against the earth-movement tlieory that 

 no evidence has been adduced that at the close of Jnrassic time similar 

 great diastrophic movements took place in America and Europe, but 

 that, on the contrary, there is a striking discordance in the periods of. 

 •diastrophism, I now desire to bring the charge against the paleontologists 

 that those who have sought to solve this important and interesting ques- 

 tion of the age of the Morrison through paleontology have never done 

 their work thoroughly; most of the paleontologists, myself included, 

 have made hasty conclusions, based on incomplete examination and com- 

 parison of material which is very rich and certainly affords ample basis 

 for more exact correlation than has yet been made.^ From the Morrison 

 alone (the Jurassic or Lower Cretaceous age of which is in dispute) 151* 

 species of animals and plants have been named as follows : 



Mammals, 25 Rhynchocepbaliau.s, 1 



Birds, 1 Crocodiles, 3 (-}- 1 in Arundel of 



Sauropodous dinosaurs, 31 (4- 8 in Maryland) 

 Arundel of Maryland) Turtles, 1 



Carnivorous dinosaurs, 13 (+ 3 in Pterosaurs, 1 

 Arundel of Maryland) Fish, 3 



Armored dinosaurs, 10-11 (-|- 1 in Species of invertebrates, 24 (+ 4 in 

 Arundel of Maryland! Arundel of Maryland) 



Isuanodont dinosaurs, 11 (Campto- Species of plants, 23 



saurs) (+ 1 ill Arundel of Mary- 

 land) 



EeSUME of CONCLSIONS OF PALEONTOLOGISTS, GEOLOGISTS, AND 



Paleobotanists 



A vast literature has accumulated. In preparation for the geologic 

 section alone of my monograph on the Sauropoda for the United States 

 (Jeological Survey, my research assistant. Dr. Charles C. Mook, has listed 

 2;59 titles in the bibliography of the Morrison formation, the greater part 

 of which deal with the geologic structure of the formation itself in dif- 

 ferent regions. There arc, besides, a large number of papers on the 

 Morrison fauna, and Hora, for we have over 300 titles on the Sauropoda 

 alone. The conclusions which have been reached by the authors of these 

 various contributions and of the papers in the following symposium are 

 as follows : 



' An exception to this statement may be made in favor of Prof. S. W. WilMston's ex- 

 cellent paper in the .Tournal of Geology for 1005 (vol. xili. May-.Tune, pp. 338-350). in 

 which he discusses the faunal relations of the Morrison. 



••The actual number of species is probably less than this as many of (he si)ecles have 

 been founded mi fragmentary material and [irobably are synonyms. 



