482 BOTANICAL GAZETTE [December 



observed in the present work, for the reason that so many soils have a greater 

 degree of acidity than existed in these experiments, and it is doubtful if they 

 will ever be limed sufficiently to maintain them in a neutral condition." 



This work should be of great interest to the ecologist and the physiologist, 

 as well as to the agriculturist. — Wm. Crocker. 



Upper Cretaceous floras. — The eastern gulf region in Tennessee, Alabama, 

 and Georgia, discussed by Berry^ with reference to the Upper Cretaceous 

 jfloras, includes that part of the Atlantic coastal plain bordering on the Gulf of 

 Mexico and lying south and west of the southern Appalachian province and 

 east of the Mississippi River. An excellent map in colors shows the exact 

 geographic location of the difTerent geological formations which contain 

 determinable plant fossils, and it appears that the bulk of the fossil floras 

 belong to the Tuscaloosa formation, with those of the Eutaw and Ripley floras 

 meagerly represented. 



The author gives a systematic arrangement of the plants found in the 

 Upper Cretaceous of the Gulf region, with a historical sketch, an account of 

 the lithologic characters of the materials associated with the fossils, and a 

 discussion of the localities with plant remains. Photographs and diagram- 

 matic sections help to elucidate the account arranged according to the different 

 localities where plant fossils have been found. After a thorough analysis of 

 the field observations made separately for the Eutaw, Ripley, and Tuscaloosa 

 formations, the composition, origin, and evolution of these different Upper 

 Cretaceous floras follow. The 151 described species from the Tuscaloosa 

 formation represent 87 genera segregated into 48 families. The pteridophytes 

 are represented meagerly, while the cycad-Hke plants, abundant in the Lower 

 Cretaceous, are represented by a single species of Podozamites and Cycadino- 

 carpus. Sixteen species of Coniferales of modern types, as Pinus, Dammara, 

 Sequoia, occur with the curious extinct phylloclad type, Andcovettia, etc. The 

 angiosperms constitute the bulk of the Tuscaloosa flora. The author explains 

 the scarcity of the monocotyledons as largely due to the fact that the lack of 

 differentiation of the leaf lamina and petiole precludes the regular shedding of 

 their leaves, which are torn to shreds by the wind, and therefore unrecognizable. 

 The dicotyledons of the Upper Cretaceous are of great interest as to their 

 origin, for they appeared with great suddenness at the close of the Lower 

 Cretaceous in America, Europe, and the Arctic region. The author beUeves 

 that North America was near their center of radiation, with the facts in accord 

 ^ith their Arctic origin and with successive waves of migration sweeping 

 southward. 



Dealing specifically with the Tuscaloosa formation. Berry emphasizes its 

 delta character with its flora of a lowland coastal type, including a number of 

 ■distinctly strand types, such as the species of Murica, the figs, and several 



7 Berry, E. W., Upper Cretaceous floras of the eastern gulf region in Tennessee, 

 Mississippi, Alabama, and Georgia. U.S. Geol. Survey, Professional Paper no. 112. 

 pp. 117. pis. 1-33. 1919. 



