STRATIGRAPHICAL GEOLOGY. 513 



the Kimmeridge group. Similar results were afterwards ob- 

 tained by Stache, Mojsisovics, and Neumayr in an examination 

 of the " Klippen " limestones in the Carpathians. These 

 geologists placed the Ammonite acanthicus strata with the 

 Upper Jurassic, the DipJiya limestones with Oppel's Tithonian 

 horizon. 



The premature death of Oppel prevented the completion of 

 the series of investigations by means of which he had intended 

 to establish the Tithonian horizon on a secure palaeontological 

 basis. The material was afterwards examined and described 

 in a series of special monographs by Zittel, Bohm, Cotteau, 

 Miss Ogilvie, and Zeise. Zittel limited the term " Tithonian " 

 to formations of Alpine facies, excluding therefore the litho- 

 graphic shale and Portland limestone, and he regarded the 

 Tithonian complex of strata as the equivalent of the Purbeck 

 and Wealden strata. 



Whereas Oppel, Zittel, and Benecke expressed themselves 

 more in favour of the Jurassic age of the Tithonian hori- 

 zon, Hebert attributed great weight to its affinities with .the 

 lowest Cretaceous deposits in the south of France (Berrias 

 strata), and even went so far as to place the Stramberg strata 

 in the Lower Cretaceous. Many eminent geologists have 

 taken part in the discussion within recent years, and the 

 opinion now most generally held is that the lower portion of 

 the Tithonian group is the equivalent of the Upper Kimmer- 

 idge horizon, while the higher portion of the Tithonian group 

 is parallel with the Purbeck and Portland strata. 



New discoveries by the Russian geologists have lately en- 

 riched the knowledge of Upper Jurassic faunas. In Central 

 Russia, marine deposits of Lower Cretaceous age succeed dark 

 argillaceous strata which represent the whole Upper Jurassic 

 series from the Kellaways zone upward. The fossils of the 

 Moscow and South Russian Jurassic deposits are now being 

 carefully examined by Trautschold, Pavlow, Sinzow, Lahusen, 

 and Nikitin, and the so-called Volga group has been identified 

 as an equivalent of the Tithonian Alpine formations. Oppel's 

 students, Neumayr and Waagen, tried to develop the zonal 

 aspect of geology more and more, and to apply it in foreign 

 parts of the world. Waagen's attempt to demonstrate almost 

 all the Upper Jurassic zones of Oppel in the Jurassic strata of 

 ditch has been contested by Kitchin and Notling. 



Neumayr advanced the paheontological knowledge of 



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