i8o REVIEWS 



These new forms appeared at higher and higher horizons as the Permo- 



Carboniferous conditions spread slowly westward and "to correlate 



widely separated groups of beds as synchronous in deposition because 



of a similarity, even approaching identity, in the fauna or flora would 



be a serious error." 



M. G. M. 



Upper Cretaceous Floras of the Eastern Gulf Region in Tennessee. 

 Mississippi, Alabama, and Geor-gia. By E. W. Berry. U.S. 

 Geological Survey, Professional Paper 112, 1919. Pp. 177, 

 pis. 33, figs. 12. 



Another publication is added to the already considerable list which 

 is making fossil plants such an important part of our geological knowl- 

 edge of the southeastern United States. 



The Upper Cretaceous of the eastern Gulf region extends in a lunate 

 outcrop around the southern end of the Appalachians. It is subdivided 

 into the Tuscaloosa formation, the Eutaw formation, the Selma chalk, 

 and the Ripley formation. These formations, with the exception of 

 the Selma, are made up largely of cross-bedded sands, with associated 

 clays. 



The most extensive flora is that of the basal Tuscaloosa formation, 

 comprising 151 species of which the majority are dicotyledonous angio- 

 sperms. The place of origin of this dominant element is left unsettled, 

 but the idea of their dispersal from an Arctic area is consistent with 

 the evidence offered by this and other Cretaceous floras. This flora 

 is made up largely of lowland coastal types, and its ecological character 

 is in accord with other evidence of the delta origin of the formation. 

 The plants make up an assemblage which most nearly resembles the 

 modern warm-temperate rain forest. In view of their northward 

 range into Greenland, they may be said to indicate a climate mild over 

 wide areas. 



The Eutaw flora comprises 43 species, most of which come from 

 the basal portion of the formation and closely resemble those from the 

 Tuscaloosa formation. The physical conditions suggested by this 

 flora are similar to those for the Tuscaloosa. 



The Selma chalk, which is described as a lithologic rather than a 

 chronologic unit, is entirely marine and contains no plant remains. 

 The Ripley formation contains a few poorly preserved plant fossils. 



The Tuscaloosa formation may be correlated, on the basis of its 

 contained flora, with the upper part of the Raritan and with the Magothy 



