158 NEW YORK STATE MUSEUM 



to investigate all the facts belonging to this curious question. I 

 would commend it to those who follow me, to whom that which I 

 have been able to do may at least be of use in guiding their 

 researches." 



Here we have a clear conception of the scope of the whole problem. 



Passing over the intervening time to the present, Schuchert's sum- 

 mary of the correlation will suffice for our purposes. He states: 



" The oldest fauna of this series at \\-indsor includes but few 

 species, and these remind one of Kinderhookian time. In the higher 

 dolomites at Windsor a rich fauna appears that is very different 

 from that in any American Mississippic horizon, and as it is also 

 unlike those of Europe it is difficult to correlate. Seemingly it is 

 of Keokuk time, yet it may be somewhat younger, as Lithostrotion 

 is reported at Pictou, which is not far from Windsor." ^ 



Characteristics of the fauna 



The faunas here discussed were collected from two islands. Grind- 

 stone and Coffin, and from five localities, as follows : On Grindstone 

 island : ( i ) close against the gypsum bluffs not far from Cape le 

 Trou on the west coast, where the rock is a very calcareous, rusty 

 sandstone; (2) near the gypsum bluff's facing the great lagoon, on 

 the property of N. Arseneau — gray calcareous shale as in the 

 locality following. On Coffin island at Oyster basin in a calcareous 

 shale; fragments of this shale have been obtained at Grand Entry 

 landing and at Old Harry point, both on Coffin island, but the former 

 v/ere transported and the latter probably not in place. 



In the Grindstone island fauna the most striking feature is the 

 peculiarity of its makeup. The brachiopods are characterized by an 

 abundance of Productus belonging to two limited groups, all other 

 groups being absent. There is also a total absence of the Spirifers. 

 A few Dielasmas are present, a Pugnax and an Orbiculoidea. The 

 Pelecypoda are well represented. Among them are Liopteria,.Paral- 

 lelidon, Modiola and Aviculopecten which constitute the majority of 

 the specimens. There are a few undeterminable gastropods, a 

 Euomphalus and a few poorly preserved ce]:)halopods. 



The Productus fauna seems to have developed from two stocks, 

 in an inclosed basin, and the species present fall into two groups, 

 the members of each group being in many ways strikingly similar, 

 but differing sufficiently to permit of careful distinction. This char- 



^ Schuchert. Palcogcography of North America. Gcol. Soc. Amcr. Bui. 

 p. 551. 1910. 



