514 HISTORY OF GEOLOGY AND PALEONTOLOGY. 



the Jurassic Cephalopods in several excellent monographs. 

 He also followed Marcou's method of discovering the biologi- 

 cal provinces of the Jurassic epoch. In Europe three pro- 

 vinces were distinguished by Neumayr a Mediterranean 

 (Alpine), a Central European, and a Russian or boreal pro- 

 vince. These were supposed by Neumayr to correspond to 

 three climatic zones which entirely girded the earth's surface, 

 and were probably repeated in the southern hemisphere. In 

 evidence of this theory Neumayr cited the fact that the 

 Jurassic fossils from South America, New Zealand, South 

 Australia, and South Africa strongly resemble those of 

 the corresponding deposits in Swabia, France, and England, 

 but differ completely from the Alpine type. Neumayr 

 (1885) likewise gave sketch-maps of the Jurassic seas and 

 continents, and pointed out the far wider distribution of 

 the Upper Jurassic deposits than of the Liassic. From this 

 he concluded that there had been an extensive Liassic conti- 

 nent which gradually became submerged by the advance of 

 the Jurassic ocean. 



According to the more recent investigations of Pompeckj 

 (1897), however, the assumed non-occurrence of the Lias in 

 the south-east of Europe, in Asia Minor, and Persia is rather 

 due to the scanty information regarding the geological con- 

 stitution of those lands than to an actual absence of the 

 Liassic deposits in those lands; in his opinion, the signifi- 

 cance of the Jurassic transgression has been over-estimated. 



H. Cretaceous System. The deposits which are now com- 

 prised under the name of the Cretaceous system were first 

 studied in the Anglo-Parisian basin. But the examination of 

 the rocks in this area provided no general systematic type, 

 according to which the contemporaneous developments in 

 other areas could readily be arranged. The remarkable differ- 

 ences in the local lithological and palaeontological facies made 

 it extremely difficult to recognise the contemporaneity of Cre- 

 taceous sediments, even in areas at no great distance from one 

 another. Hence the geological knowledge of this system 

 advanced slowly and in a fragmentary way. The sequence of 

 rocks and organic types had to be independently elucidated in 

 each locality. And it has been found impossible to determine 

 any constant succession of faunal zones applicable over larger 

 tracts of country, such as geologists have established for the 



