282 



The Ohio Naturalist. 



[Vol. XI, No. 4, 



The following section gives the general relations and more 

 important subdivisions of the Triassic of Brazil: 



fSerra Geral eruptives 600 m. 



Sao Bento sandstones, cliffs 

 of red gray and cream 

 colored sandstones 200 m. |-900 m. 



Rio do Rasto red beds with 

 fossil Reptiles and fossil 

 trees 100 m.. 



Sao Bento series 

 (Triassic) 



Santa^^ 

 Catharina ■ 

 System 



Passa Dois series 223 m. 



(Permian) 



, ISO m. 



Tubarao series 



(Permo-Carboniferous) 



The Rio do Rasto beds are composed of loosely consolidated 

 red sands and conglomerates, while the Sao Bento beds consist of 

 massive red, gray, and cream-colored sandstones which are some- 

 times conglomeratic and "often baked and vitrified by contact 

 with the great sills of diabase which are so frequently intercalated 

 between the massive layers as well as piled on top of the same/^^ 

 The lower part of these beds (Sao Bento) are mostly red sandstone 

 flags and the whole is apparently unfossihferous. The hard 

 vitrified rocks of the upper part of the series frequently form 

 walls, towers, and buttes near the summits of the elevated peaks. 

 The top of the section is made up of a great series of lava flows and 

 the beds beneath are affected by numerous dikes and intrusive 

 sheets. 



The coal-bearing strata of southern Brazil is late Paleozoic, 

 while that of Argentine and the Chilian Cordilleras belongs to the 

 Rhaetic group and is partly covered by conformable marine 

 deposits of lower Lias.'*'' 



The Triassic fossils of the Cordilleran region are of the same 

 type as those found in California and western Canada, the leading 

 fossil being Pseudomonotis semicircularis (?) Graft. 



Nearly all horizons of the Jurassic have been found to be 

 fossihferous and "the rich collections made in different parts of" 

 the Argentinian, Chilian and Perrtvian Cordilleras have enabled 

 us to detennine 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. "^^ 



38. White, I. C, Commissao de Estudos das Minas de Carvao de 

 Pedra do Brazil. Relatio Final, 1908, p. 33. 



39. White, I. C, loc. cit., p. 211. 



40. Steinmann, Gustav, loc. cit., p. 857. 



41. Steinmann, Gustav, loc. cit. p. 857. 



