16 NEW YORK STATE MUSEUM 



Correlation of New York faunas with those of Canada. Portions 

 of the succession of rocks and their faunas in the paleozoic series 

 are less completely represented in the state of New York than 

 in parts of the Dominion of Canada. Among the problems which 

 are now of immediate interest to American paleointologists is that 

 of the age of the Helderbergian fauna and formation and its 

 equivalents in other countries. In the consideration of this sub- 

 ject, which involyes the question of the Siluric or Deyonic age 

 of the fauna in question, the paleontologist has taken ground in 

 fayor of its reference to the later geologic age as a representative 

 •of the opening stage of Devonic time in the deposits of the New 

 York series. For additional light on this important theme 

 it became desirable that the faunas and the rock series at 

 Arisaig (N. S.) Dalhousie (N. B.) and Gasp^, Quebec, should be 

 restudded in the light of the present evidence. The rock strata 

 and their fossil contents at all of these localities had in time past 

 been correlated to a greater or less extent mth the New York 

 Helderbergian. With the proper authority the state paleontolo- 

 gist has spent some weeks in a careful study of the rock series 

 at these points. At Arisaig (N. S.) the exposure is wonderfully 

 displayed aloiig the seacoast on the northern shore of the penin- 

 sula, and the faunas of the series were long ago carefully ex- 

 ploited by Canadian and English geologists, principally by the 

 late Dr. Honeyman of the Nova Scotia institute at Halifax. 

 Very considerable collections were made from these interesting 

 series. The effort on the part of the early Canadian geologists 

 to correlate their paleozoic formations with the New York 

 series led to some misinterpretations, because of the omissdon to 

 recognize the fact that in geologic time of the date of the Arisaig 

 series the sea depositing these sediments on the eastern coast 

 was so completely cut off from that forming the sediments in the 

 New York basin that they constituted two altogether distinct 

 marine provinces. Under such circumstances correlation must 

 take account of notable faunal diff'erences. The fauna of the 

 Arisaig series., more paiidcularly that of its later beds, indicates 

 quite clearly a typical Siluric fauna without relations of special 

 moment to that of the Helderbergian stage in New York. 



