REVIEWS 
Geology and Paleontology of the Raton Mesa and Other Regions in 
Colorado and New Mexico. By Wits T. LEE and F. H. 
Know ton. U.S. Geological Survey, Professional Paper 
IN; WO; MON7e 1e\Os AUK, JOS, EAA, WIGS, a0), 
This interesting paper presents many details concerning the geology 
of the areas indicated by the title. To the general reader the large 
interest of the paper centers in the correlation of disputed formations 
in the several regions discussed, and in the attempt to establish their 
time-relations to formations elsewhere. Some of the significant con- 
clusions are the following: 
“The coal-bearing rocks of the Raton Mesa region which have 
formerly been referred to the Laramie constitute two distinct formations 
separated in time by a period of erosion.” The lower of these two 
formations (Vermejo) contains a Montana flora, and ‘‘is more closely 
related to the Mesa Verde of western New Mexico than to any other 
formation we have examined.” The coal-bearing rocks of the Canyon 
City field are correlated with the Vermejo, which is thought to be 
approximately equivalent in age to the Fox Hills formation of the 
Denver basin. 
“The upper coal-bearing formation of the Raton Mesa region, to 
which the name Raton is here applied, is Eocene in age and contains a 
flora distinct from that of the Laramie of the Denver basin, but similar 
to that of the post-Laramie formations of that basin and to that of the 
Eocene Wilcox group of the Gulf coast.” 
“The unconformity between the Vermejo and Raton formations 
represents a time interval comparable to that ... . separating the 
Laramie from the Arapahoe of the Denver basin.” 
“The coal-bearing rocks of the Cerrillos, Hagan, Tijeras, and Rio 
Puerco fields are essentially equivalent in age to the Mesa Verde of the 
San Juan basin.” 
The plants of the formations described in this paper are discussed by 
Mr. F. H. Knowlton, who indicates that the flora of the Raton formation 
indicate “‘a relatively moist, warm situation, whose temperature did 
not fall much if any below 42°F,” and that the floral hiatus between the 
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