100 BARON F. NOPCSA ON THE PRIMITIVE REPTILIA [vol. lxxix, 



4. On the Geological Importance of the Primitite Reptilian 

 Fauna in the Uppermost Cretaceous of Hungary ; with 

 a Description of a New Tortoise (Kallokjbotion). 

 By Baron Francis Nopcsa, For. Corresp. G.S. (Read 

 March 8th, 1922.) 



Contents. 



Page 



I. The Age of the Reptiliferous Strata 100 



II. The Vertebrate Fauna 103 



III. Comparison of the Fauna with others 107 



IV. Palaeogeographical Data 109 



V. The Causes of the Extinction of the Upper 



Cretaceous Vertebrates 110 



VI. Bibliography 113 



I. The Age of the Reptiliferous Strata. 



In Eastern Hungary 1 the Upper Cretaceous can be divided into 

 two horizons with an unconformity between them (53, 66 ). 3 The 

 lowest deposits in some places, as near Szaszcsor (53), are red con- 

 glomerates; in other places (as, for example, Ohaba Ponor) they are 

 red laterites filling fissures in the Tithonian limestone (28). Then 

 follow, extending farther than the red deposits, grey marls and 

 sandstones containing at their base seams of coal (28), and some- 

 what higher up several ammonites, such as : 



Acanthoceras neivboldi Kossmat. Acanthoceras mantelli (Sowerby). 



A. cenomanense Pictet. A. morpheus Stoliczka. 



A. harpax Stoliczka. Puzosia planulata (Sowerby). 



A. rhotomagense (Defrance). Crioceras sp. (53). 



These help to fix the age of the marls as Cenomanian. Overlying 

 the ammonitiferous strata are coarser sandstones, crammed with 

 enormous numbers of Actceonella sp. (28, 53) ; then come marls 

 and sandstones containing some rare examples of Actceonella 

 gigantea (53), attaining a diameter of 6 inches and more ; and 

 lastly, a great complex of rough blue and white sandstones is met. 

 with (7), corresponding to the Emscher Sandstone of German 

 geologists or to the zone of Mieraster cor-anguinum in England. 

 These strata are characterized throughout Transylvania by re- 

 markably large Inocerami (53, 65). In Inoceramus gigantens 

 Palfy, for exanrple, each valve attained a length of nearly 2 feet 

 (65). 



1 Under the term Hungary, not the area politically so defined is meant, 

 but that basin which since Upper Senonian times has had for its rim the 

 range of the Carpathians. 



2 Numerals in parentheses refer throughout to the Bibliography, § VI, 

 p. 113. 



