EARLY DEVONIC HISTORY OF NEW YORK AND EASTERN NORTH AMERICA 



43 



the St Alban and Grande Greve faunas and it is emphatically true again 

 of the Dalhousie fauna. 



Strop heodonta (Brachyprion) major, S . ( B . ) schu- 

 chertana and S. patersoni protype bonamica work back upon 

 analysis to differently progressed expressions of S. varistriata; the first 

 is a fasciculate shell in later stages, the second a finely plicate, nonfasciculate 

 shell and the third both fasciculate and undulate. 



by Charles Sc tuichert 



Shore section of Dalhousie beds, divisions n, i^, 13. Stewart's cove 



Stropheodonta varistriata Conrad 



Plate 8, figures 21-24 



Some of the expressions of this shell are here represented. They show 

 very much the same individual differences as are found in and have been 

 illustrated from the New York shell. 



Horizon. Nos. 8, 9. 



