664 abstracts: technology 



ment are discussed in great detail. The Wilcox flora is one of the most 

 extensive American fossil floras known from a single horizon in a single 

 area, and it includes a large number of types hitherto unknown from 

 North America and more than 200 species new to science. It contains 

 ] arge numbers of figs, lauraceae, and leguminosae and is prevailingly a 

 strand flora, subtropical in character, which invaded southeastern 

 North America from the equatorial region at a time when the Missis- 

 sippi Gulf reached northward to southern Illinois and covered nearly 

 all of the states of Mississippi and Louisiana as well as a large area in 

 Alabama, Tennessee, Arkansas, and Texas. The Wilcox deposits are 

 definitely correlated with the Sparnacian and Ypresian stages of the 

 European lower Eocene section. E. W. B. 



GEOLOGY. — The Catahoula sandstone and its flora. George Charl- 

 ton Matson and Edward Wilber Berry. U. S. Geological 

 Survey Professional Paper 98-M. Pp. 209-259, with 13 plates 

 and 7 figures. 1916. 

 The Catahoula sandstone is redefined and its lithology, topography, 

 structure, thickness, origin, and stratigraphy are discussed. It is 

 shown that in central Louisiana this formation is interbedded with 

 lower Oligocene limestones and marls of the Vicksburg formation, 

 while near the Texas line it replaces all of the marine lower Oligocene. 

 Across Mississippi the Catahoula lies above the Vicksburg, and east- 

 ward in Alabama and western Florida it merges into the marine beds 

 of the Chattahoochee formation. 



TECHNOLOGY. — The density and thermal expansion of American 

 petroleum oils. H. W. Bearce and E. L. Peffer. Bureau of 

 Standards Technologic Paper No. 77. Pp. 26. 1916. 

 This paper gives an account of the experimental work on which are 

 based the expansion tables of Bureau of Standards Circular No. 57, 

 United States standard tables for petroleum oils. It gives a detailed 

 description of the methods and apparatus employed in the determina- 

 tion of the density and thermal expansion of petroleum oils from the 

 various oil fields of the United States. H. W. B. 



