THE 



AMERICAN JOURNAL OF SCIENCE 



[FOURTH SERIES.] 



Art. I. — Dinosaurian Distribution/ by Richard S. Lull. 



[Contribution from the Paleontological Laboratory, Peabody Museum, 

 Yale University.] 



I. Introductory. 



II. Classification. 



III. Habitats and adaptations. 



IV. Geological distribution. 

 V. Geographical distribution. 



VI. Summary of migrations and paleeogeography. 

 VII. Bibliography. 



Dinosaurian Distribution. 



I. Introductory. 



The significance of terrestrial vertebrates of bygone days 

 as aids to geological interpretation, and especially in throwing 

 light upon the isolation and connection of continents, is becom- 

 ing more and more appreciated. 



The dinosaurs, with their known geological range through- 

 out nearly the entire Mesozoic period, and of almost world- 

 wide distribution, are the most significant vertebrates of 

 Secondary times. Add to this their great numbers both of 

 individuals and kinds and the amazing range in their adapta- 

 tions and one can appreciate the importance of the line of 

 research of which this paper is the first fruit. It constitutes 

 the further elaboration of a presidential address delivered 

 before the American Society of Vertebrate Paleontologists 

 at Baltimore, December, 1908. 



As such a work is of necessity to a certain extent a compila- 

 tion, I can but express my indebtedness to the various authors 

 listed in the Bibliography, of whom my confrere, Professor 

 v. Huene, is the one to whom I owe the most. I am also 



Am. Jour. Sci. — Fourth Series, Vol. XXIX, No. 169.— January, 1910. 

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