ILLUSTRATIONS OF THE DEVONIC FOSSILS OF 

 SOUTHERN BRAZIL AND THE FALKLAND ISLANDS 



BY JOHN M. CLARKE 



Three years ago the writer completed a protracted series of 

 studies on the Devonic faunas of South America, especially 

 those of southern Brazil in the state of Sao Paulo, and of the 

 Falkland islands, incidentally also of the Cordilleras of western 

 Argentina. These studies Avere authorized by the director of 

 the Geological Service of Brazil, and the full discussion of these 

 austral faunas is in course of printing as a memoir of that or- 

 ganization. Meanwhile, because of the delays attendant on pub- 

 lication in Brazil, and by permission of the director of the Brazil- 

 ian Survey, occasion is here taken to present illustrations of the 

 leading species of the Brazilian and Falkland faunas which are 

 with propriety incorporated in this report on account of their 

 intimate but contrasting relations to the Devonic faunas of New 

 York. 



While no other purpose is here sought than to set forth, as 

 well as may be by illustration, the distinctive fossil characters 

 of this southern Devonic and the whole estimate of the real 

 significance of the fauna must be reserved for its more complete 

 presentation and discussion, it is well to intimate that these 

 Devonic faunas of the south and of the north, though united by 

 general characters, are keenly and widely separated in the analy- 

 sis of their specific and superspecific structures. This fact makes 

 itself so clear that it is evident the northern and southern faunas 

 developed in separated basins with but restricted intercommuni- 

 cation during the Devonic. These illustrations also indicate the 

 continuity of the strand line and of the Devonic continents from 

 southern South America to the Falkland islands and thence to 

 South Africa. 



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