28 



Inxkoduction 



ment of the species. x\d early colony arrived in New York in Genesee 

 time while the main body appeared in Portage time. The accompanying 

 map (fig. 1) shows the conditions in New York as interpreted by Clarke. 

 The Naples fauna inhabited the Genesee province in the west and the Ithaca 

 fauna dwelt in the Ithaca province in the central part of the state, while 



Fig. 1. — Sketch map showing the biologic provinces of the Upper Devonian 

 sea in the New York area. (After Clarke.) = Oneonta Province; I =: Ithaca 

 Province; Gn == Genesee Province, Naples subprovince; Gc = Genesee Province, 

 Chautauqua subprovince. 



an embayment, closed in the northeast, existed in the vicinity of Albany 

 in which lived fresh and brackish water species. The last is termed the 

 Oneonta province by Clarke. As the level of the sea oscillated, leading to 

 the interleaving of the two types of containing sediments in central New 

 York, the Naples and Ithaca faunas migrated back and forth. That these 



