274 REVIEWS 



He discusses at some length the evidences of the age and extent of the 

 Permian glaciation, and cites the observations of a number of geologists 

 and travelers upon the occurrence of the strata and fossils by which they 

 have been identified. He distinguishes the Upper and Lower Permian, 

 both in his text and on the map, except that he has not indicated the 

 boundary between the two where its location is not definitely known, on 

 the headwaters of the Rio Sao Francisco. The Upper Permian is de- 

 scribed as unconformable upon the Lower, but the break is marked only 

 by a change in sedimentation. 



The coal beds of Parana, Santa Catharina, and Rio Grande do Sul 

 are economically important, as are also the Permian bituminous shales 

 of the southern states. The limestones will yield materials for the manu- 

 facture of Portland cement. 



The pre-Mesozoic rocks, including the Permian, constitute the 

 mountains and plateaus of all of eastern Brazil, which is thus a great 

 geologic province whose history since the close of the Paleozoic has been 

 that of a continental area subject to erosion. With the exception of 

 small areas of Tertiary rocks along the Atlantic Coast and an embayment 

 of Cretaceous and Tertiary strata in Bahia and Piauhy there are no post- 

 Paleozoic sediments in the area. 



The Mesozoic rocks occur southwest and west of the great Brazilian 

 plateau. They comprise the red sandstones of the Trias, extensive out- 

 flows of pre-Cretaceous igneous rocks, and sandstones and limestones of 

 Cretaceous age. The Trias is most widely represented in western Sao 

 Paulo and southern Goyas. The igneous rocks, erupted through the 

 Trias and spreading out as very extensive lava flows similar to those of 

 the Columbia lavas, occur in Rio Grande do Sul, Santa Catharina, 

 Parana, and Sao Paulo. They occur as interbedded sheets exposed 

 along the canyon of the Parana, where, on account of the small scale, the 

 coloring of the map gives an appearance of a widespread igneous mass 

 under the Trias. 



The Cretaceous is distributed in the form of remnants capping the 

 Triassic plateaus, and extends northwest across Matto Grosso to the 

 Andes and also north to the Amazon Valley. In the northwest and 

 north it appears to rest directly upon the Brazihan complex, the older 

 rocks being absent. 



The Tertiary formations of Brazil are briefly described as comprising 

 freshwater and land deposits of the territory of Acre, brackish water 

 deposits in Amazonas, and marine deposits in Para, Maranhao, and also 

 in Rio Grande do Norte. Marine Tertiary occurs along various sections 



