THE 
LoOwnN A OF GEOLOGY 
OCTOBER-NOVEMBER, 1907 
PERMO-CARBONIFEROUS CLIMATIC CHANGES IN 
SOUTH AMERICA 
DAVID WHITE 
INTRODUCTION 
The presence in Argentina and Brazil of representatives of the 
Lower Gondwana, or Gangamopteris flora has for some years been 
definitely recognized through the small collections examined by 
Professors Zeillert and Kurtz.? More recently, however, the Coal 
Commission of Brazil has placed in the writer’s hands a number of 
fossil plant collections which, though lacking much both in quantity 
and preservation, are definitely fixed stratigraphically, while embra- 
cing a considerable vertical range. 
The new material, from the coalfields, chiefly of the states of 
Santa Catharina and Rio Grande do Sul, in Brazil, not only confirms 
the presence in that country of the Lower Gondwana flora, but it 
also throws new light on the geographical relations and climatic 
changes in this quarter of the earth during Permo-Carboniferous 
time. The purpose of this paper is particularly to call attention to. 
some of the physical conditions indicated with more or less distinct- 
ness by the fossil floras, and briefly to state the conclusions drawn or 
opinions entertained by the writer in an attempt to account for certain 
changes in climate. 
t Comptes Rendus, Vol. CXXI, 1895, p. 961; Bull. Soc. géol. Fr. (3), Vol. XXIII, 
1896, p. 601. 
2 Rev. Mus. de la Plata, Vol. V1, 1894, p. 125; Bull. Soc. géol. Fr. (3), Vol. XXIV, 
1896, p. 466. 
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