ioo E. M. KINDLE 



lachia was not elevated and the Devonian shoreline was not pushed 

 westward at the initiation of Onondaga time, we would still expect 

 as a probability non-calcareous sediments to predominate in the 

 eastern portion of the Onondaga sea. That portion of the Onon- 

 daga sea adjacent to the land area which furnished 10,000 feet of 

 non-calcareous Devonian sediments in post-Onondaga time would 

 be likely to acquire chiefly non-calcareous sediments even in an 

 epoch so favorable to calcareous sedimentation as the Onondaga. 

 A considerable mass of paleontologic and stratigraphic data 

 which has been gathered by the writer shows that Onondaga sedi- 

 ments are present in the Allegheny region and are mainly of this 

 non-calcareous type, as might have been expected from theoretical 

 considerations. The recent discovery of an Onondaga fauna 

 in the Allegheny region which occurs in a series of drab or 

 dark shales and thin interbedded argillaceous limestones thus 

 very materially supplements the hitherto one-sided character of 

 the available data relating to the nature of the fauna and sediments 

 of the Onondaga sea. The sediments holding this fauna are of 

 such a character as we might have expected to be accumulating 

 on some portion of the Onondaga sea floor if we may judge by 

 analogy with the processes of sedimentation now in operation in 

 the largest continental seas. Since this fauna will be described and 

 figured in a forthcoming bulletin of the United States Geological 

 Survey, only the most general facts regarding it will be presented 

 here. The fauna comprises more than one hundred species. The 

 correlation of this Allegheny fauna with the New York Onondaga 

 fauna is based primarily upon the presence in it of such well-known 

 species as Anoplotheca acutiplicata, Rhipidomella vanuxemi, Spirifer 

 acuminatus, and Odontocephalus aegeria. The great abundance and 

 general distribution of the first named of these species is a con- 

 spicuous characteristic of the fauna. In point of abundance and 

 wide distribution in this argillaceous facies of the Onondaga, 

 Anoplotheca acutiplicata is as prominent as is Spirifer acuminatus in 

 the well-known calcareous facies. It is interesting to note in this 

 connection that while Anoplotheca acutiplicata is a familiar species 

 in the Onondaga limestone of eastern New York comparatively near 

 the region under discussion, it is unknown in the more westerly areas 



