the Limits of the Jurassic and Cretaceous Periods. 329 



regions. In one (Provence, Saleve,Wimmis) the stages are nearly 

 conformable to what we find in the rest of France, and terminate 

 in the littoral Neocomian ; the limits of the Jurassic and Creta- 

 ceous appear there to be distinct. In the other, comprised be- 

 tween the Carpathians and Italy (with a portion of the French 

 Alps, of the Department of the Isere, &c), the Tithonian stage 

 rules on the confines of the two great periods. 



It is to this latter form of succession that we have to direct 

 our attention. In this affairs have taken place in a very differ- 

 ent manner from that which characterizes the Anglo-French 

 basin. To be convinced of this, we have only to study the 

 recent investigations of M. Zittel* in the central Apennines, 

 and those of M. Neumayrf in the Carpathians. These works 

 seem to prove that the Tithonian stage must be divided into two, 

 neither of which, indeed, is perfectly identical with the fauna of 

 Terebratula moravica, for both of them are rich in Ammonites. 



In the central Apennines the Tithonian stage is strongly de- 

 veloped and abounds in fossils, but, according to M. Zittel, it 

 presents peculiar palseontological conditions. Of forty-five species, 

 consisting in great part of Cephalopoda, there are thirty-one in 

 common with the Dip hy a-limestone of the Tyrol, and twenty-nine 

 with the breccia of Rogoznik. Its analogy with Stramberg is 

 less, and supported by only thirteen species. 



From this and from different comparisons, M. Zittel infers 

 that the Tithonian stage, as we have just stated, forms two divi- 

 sions. The superior of these is the Stramberg limestone, the 

 fauna of which has more analogy to Cretaceous than to Jurassic 

 forms. It corresponds to the coralline beds of the Wolfgang- 

 lake, and also to the lithographic beds of the Porte-de- France 

 and of Aizy. 



The lower one, which nevertheless evidently forms part of the 

 same whole, includes the greenish marble of the central Apen- 

 nines, the diphya-limestone of the Tyrol, and the Klippenkalk 

 of Rogoznik. The fauna has a more Jurassic character than 

 that of the other division. Out of forty-five species only one is 

 Cretaceous, and at least four are Jurassic. 



M. Neumayr has studied the formations situated between 

 Rogoznik in Galicia and the county of Saros in Upper Hungary, 

 along a long and narrow band. These formations present an 

 interesting and instructive series of faunas, which, like the in- 

 vestigations of M. Zittel just cited, show the extreme difficulty 

 that there is in finding a limit between the Jurassic and Creta- 

 ceous periods in the vicinity of the Tithonian stage. 



* M. Benecke's Geogn.-pal. Beitrage, vol. ii. part 2. Munich, 1869. 

 t " Ueber Dogger und Malm im penninischen Klippenzug," Verhandl. 

 der K. K. geol. Reichsanstalt, 1869, No. 5. 



