406 ^V. D. MATTHEW PROGKESS IN VERTEBRATE PALEONTOLOGY 



judge from the record maps of the Jensen quarry, which I had the 

 privilege of inspecting through the courtesy of Mr. Douglass, the material 

 secured there is greater in quantity and finer in quality than the sum of 

 all that has been obtained hitherto in America. The preparation of this 

 huge collection will be a labor of many years, however it be arranged; 

 but as a result we may look forward confidently to more than doubling 

 our present knowledge of Morrison dinosaurs. 



The memoirs by Gilmore^^ on the carnivorous and armored dinosaurs 

 in the National Museum, chiefly of the Morrison fauna, are of the highest 

 authority and importance and his restudy of the Potomac fauna^^ of 

 Lower Cretaceous age shows that it is not the Morrison, as formerly sup- 

 posed, but of decidedly later age. The Tendaguru collection is likewise 

 an immense task in preparation, and when I saw it in Berlin, two years 

 ago, it was far from being completed, after more than ten years' work. 

 It provides a fairly complete skeletal knowledge of some half-dozen types 

 of dinosaurs^* and fragments of a few others, representing a fauna similar 

 in broad lines to the Morrison fauna, nearly similar in its adaptive f acies, 

 and approximately of the same age, but inhabiting a different continent, 

 and of the highest importance in giving some really adequate data as to 

 the faunal distribution at that epoch. It is too early yet to draw conclu- 

 sions, but my impression from a superficial review was that the Tenda- 

 guru and Morrison faunas showed a very close adaptive similarity, but 

 were not so closely related as they seemed. It is, fortunately, possible to 

 correlate the Tendaguru dinosaurs exactly through marine faunas in 

 interdigitating formations. This in turn aids greatly in the correlation 

 of the Morrison fauna, and Schuchert has shown^^ that there is strong 

 reason to place it rather at the end of the Jurassic than at the beginning 

 of the Cretaceous. This .conclusion is further supported by Gilmore's 

 new evidence as to the relations of the Potomac fauna. 



^- C. W. Gilmore : (1920.) Osteology of the carnivorous dinosauria in the U. S. Nat. 

 Mus., Bull. 110, U. S. Nat. Mus. ; 1914, Osteology of the armored dinosauria in the U. S. 

 Nat. Mus., Bull. 89, U. S. Nat. Mus.; see also 1909, Osteology of Camptosaunis ; 1915, 

 Osteology of Thescclosaurus, and other articles in Proc. U. S. Nat. Mus. 



13 C. W. Gilmore: (1921.) Fauna of the Arundel formation of Maryland. Proc. U S. 

 Nat. Mus., vol. lix, pp. 581-594, pis. cx-cxiv. 



iMV. .Janensch : (1914.) Uebersicht ueber die Wirbelthierfauna der Tendaguru-Schich- 

 ten. Archiv. f. Biontologie, III, 79-lJ.O ; also pp. 217-261. Ueber Elaphrosaurus u. s. w., 

 Sitzber. Gesell, naturf. Freunde, 1920, pp. 225-235. 



W. Branca : (1914.) Die Riesengrobe sauropoder Dinosaurier vom Tendaguru, u. s. w. 

 Archiv. f. Biontologie, vol. iii, pp. 71-78. 



Pompeckj : (1920-1923.) Personal communications. 



E. Hennig: (1912.) Am Tendaguru; also various articles in Sitzber. Gesell. naturf. 

 Freunde, 1912-1922. 



1^ C. Schuchert: (1918.) Bull. Geol. Soc. Am., vol. 29, pp. 245-280. 



