THE INDIGENE AND ALIEN FAUNAS OF THE NEW YORK 



DEVONIC 



BY JOHN M. CLARKE 



This paper has been suggested by the important propositions 

 presented in the preceding article which was prepared by 

 Messrs Ulrich and Schuchert at the urgent solicitation of the 

 state paleontologist. The existence of a Paleozoic Appalachian 

 channel parallel to the orographic features of the eastern 

 border is recognized by the writer as an indispensable factor to 

 the proper apprehension of the sequence and geographic rela- 

 tions of the New York faunas. The full value of the considera- 

 tions set forth by the accomplished authors will be better 

 measured when time has permitted an adjustment of contend- 

 ing evidence by a more complete array of facts. In the follow- 

 ing, however, it is in part intended to show, irrespective of the 

 finer analysis of the shore topography, in what manner the 

 Devonic faunas of New York indicate the influence of such 

 Appalachian channel. 



By an indigene fauna is meant, in this paper, one which, tak- 

 ing possession of the marine province at an early date, held the 

 ground (subject to variations in its species combination) for a 

 long period, during which may have occurred various minor in- 

 vasions. This is the correct significance of the term, as every 

 indigene fauna is alien in its inception. 



The Appalachian gulf, or marine water of the New York 

 Devonic, had its northern coast line at the opening of this 

 period probably not far south of the present south line of 

 Lake Ontario and the course of the Mohawk river. This state- 

 ment is made assumptively, as the northern shoreward edges 

 of the sediments of the period have been removed. We may 

 say with some assurance that this continent line was 

 no farther south; it may however have been situated 



