[AxxalS N. Y. Acad. Sci., Vol. XXII. pp. 9-112. pll. II-XVI. 31 May. 1912] 



SOME FACTORS OF GEOGRAPHICAL DISTRIBUTTOX IX 

 SOUTH AMERICA 



By Johx D. Haseman 



[Presented in abstract before the Academy, 12 February, 1912] 



CONTENTS 



Page 



Introduction 10 



Part I. Geology and topography of South America 17 



Distribution of geological horizons IT 



Trend lines 22 



Brazilian coast 25 



Piano Alto and the Permian Inland Basin 27 



East Andean Sea 30 



Reversal of Rio Amazonas v 33 



Stream piracy 38 



Barriers to aquatic migration and conditions of environment 42 



Part II. Distribution of the South American fishes and its bearing upon 

 alleged connections between South America and the eastern 



hemisphere 50 



Distribution of the fishes 50 



Introduction 50 



Use of characters 55 



Ichthyological fauual regions 58 



Rio Uruguay and Rio Grande do Sul. including part of the lower La 



Plata 62 



Alta Parana and coastwise streams of eastern Brazil 63 



Sao Francisco and the Secca (dry) region of northeastern Brazil 64 



The Paraguay as part of the Amazonian complex 64 



Rio Amazonas region 66 



Origin of the South American fishes 75 



Summary of the most important data which have been used to support the 

 view that South America and the eastern hemisphere were primitively 



connected 80 



Invertebrates 80 



Crustacea - 80 



Mollusca 80 



Ants 83 



Corals 83 " 



Gondwana flora 84 



Permian reptiles 95 



Mammals 99 



Summary 103 



Bibliography 106 



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