THE KARROO SYSTEM 237 



these three countries boulder-beds, supposed to be of 

 glacial origin, lie at or near the base of a group of rocks 

 which contain typical genera and species of the Glos- 

 sopteris flora. 



The most complete account of any of these rocks is 

 that published by the Brazilian Government, 1 and there- 

 fore more will be said here about that region than the 

 others. The Brazilian formation is called the Santa 

 Catharina system, which is over 4,000 feet thick, and is 

 subdivided as follows : 



~ ~ . 



Sao Bento series 



Volcanic rocks (basalts, etc. ) 

 Sao Bento sandstone 

 I Rio do Rasto red beds (Sca- 

 phionyx) 



f Estrada Nova beds 



Passa Dois series \ T , , , ,,, x 



I Iraty shales (Mesosaurus) 



Palermo shales 



Rio Bonito beds (Glossopteris, 

 Rio Tubarao . -77-7, -, , N 



Sigillana brardi etc.) 



Orleans conglomerate 



Sta. Catharina 

 system 



(glacial) 



The Orleans conglomerate is in many respects like 

 the Dwyka ; it lies either directly and unconformably 

 upon beds containing Leptocoelia flabellites and other 

 Lower Devonian fossils, or upon granite, or there may 

 be some sandstone and shale below the conglomerate. 



1 Final Keport of the Coal Commission presented to Dr. L. Miiller ; by 

 I. C. White ; Kio Janeiro, 1908. This contains not only an account of 

 the Geology of Southern Brazil with regard to the coal supply, but de- 

 scriptions of Mesosaurus by J. H. Macgregor, of Scaphionyx by A. Smith- 

 Woodward, and of the fossil plants by D. White, who also gives a valu- 

 able discussion on the correlation and climatic questions raised by the 

 work of the Commission. See also D. White, Journal of Geology, xv., 

 1907, p. 615. 



