



1891.] A Sketch of the Geology of South America. 857 
During the Permian, Triassic, and Jurassic epochs the greatest 
part of the South American continent, in the same manner as the 
North American, was above the sea-level, for according to the 
‘researches made by Brackebusch in the Argentine Republic, by 
myself in Bolivia, and by Derby in the Matto-Grosso region, a great 
if not the greatest, part of the redsandstones generally considered 
to be of Permian or Triassic age seems to belong to the Cretaceous 
formations,—probably to the lower part of it. The flora which 
existed during the Permianand Triassic periods upon the South 
American continent is of high interest. The coal-bearing 
deposits of South Brazil and those of the Argentine and Chilian 
Cordilleras contain many representatives of the so-called “ Glosso- 
pteris flora” known from South India, Australia,and South Africa. 
The age of these coal deposits is not everywhere the same. The 
flora of South Brazil has been referred to the younger Paleozoic, 
because it contains some Paleozoic types of plants; those of the 
Argentine and Chilian Cordilleras belong tothe Rheetic group, 
and are partly covered conformably by marine deposits of the 
Lower Lias. 
Marine deposits of the Triassic and Jurassic formations have 
only been found in the western part of the continent,—namely, in 
the Cordillera between the 5° and 35° of southern latitude. The 
Triassic fossils are of the same type as those found in California 
and Western Canada, the leading fossil being a species of 
Pseudomonotis of the group of Ps. semicircularis Gatt. From 
the Jurassic formation nearly all horizons have been found in 
a fossiliferous state, and the rich collections made in different parts 
ofthe Argentine, Chilian, and Peruvian Cordilleras have enabled 
us to determine that the succession of marine organic life during 
this period was quite the same on the Pacific slope as in Europe 
and East India, and there have existed very intimate faunistic 
relations between these regions. As regards the extension of 
marine deposits of the Triassic and Jurassic epochs, there exists 
a remarkable similiarity between North and South America, 
being themselves confined to a small strip parallel to the Pacific 
coast. 

