102 E. M. KINDLE 



evidence already briefly cited in pointing to the Onondaga age of 

 the fauna. We may now consider the bearing of the data which 

 have been cited on the modification of the current conception of 

 the eastern shoreline of the Onondaga sea in the eastern United 

 States. 



The Onondaga formation extends scarcely south of the Dela- 

 ware River according to most of the papers dealing with the stratig- 

 raphy of the Devonian in the Allegheny region, thus giving it a 

 north-south extension of scarcely 200 miles. This comparatively 

 insignificant southerly extension of a fauna which is so persistent 

 in a westerly direction seems more surprising when it is recalled 

 that all of the other faunas characterizing the major divisions of 

 the New York Devonian section have with one or two exceptions 

 been traced southward from New York entirely across Pennsyl- 

 vania. Thus it* is seen that the prevailing conception of the 

 Onondaga formation and fauna, which presumes their absence 

 south of New York, gives to it an anomalous position as compared 

 with the other important formations of the Devonian section of 

 New York. The evidence which the writer has gathered during 

 three seasons of field work in the Allegheny region indicates that 

 the southerly extension of the Onondaga fauna is quite comparable 

 in distance with its westerly extension. The field studies of the 

 writer have shown that the Onondaga fauna in the Allegheny region 

 extends far to the southward of the area in which nearly pure 

 limestones were deposited during Onondaga time into a region where 

 shale-forming sediments partially or completely dominated those 

 of calcareous type. This fauna has been found in nearly all the 

 sections studied from New York to Tennessee. 



The direct bearing of these new data on the paleogeography of 

 Onondaga time is obvious. Its incorporation involves the exten- 

 sion of the eastern shoreline of the Onondaga sea in a southwesterly 

 direction from southeastern New York to the eastward of the 

 Allegheny region instead of far to the westward of it, as now drawn, 

 across the states of Ohio, Indiana, and Kentucky. In the light 

 of this new evidence it appears that the eastern shoreline of the 

 Onondaga sea trended southwesterly across north-central New 

 Jersey and southeastern Pennsylvania. It probably traversed the 



