ii>4 



NEW YORK STATE MUSEUM 

 PLATE 21 



FIG. 

 I 



2, 3 



4-8 



Phragmoceras parvum Hall & Whitfield 



Page 99 



Lateral view of a relatively large specimen with well preserved 

 surface sculpture 



Two views of a specimen, showing the curvature of the apical 

 part, the last camerae, the living chamber and the different 

 direction of the septal sutures and surface lines 



Five views of a specimen, showing the long and narrow hypo- 

 nomic area of the contracted aperture and the hyponomic 

 curve of the growth lines upon the ventral side (fig. 7) 



All figures are natural size. The originals are from Roch- 

 ester (Arey collection). 



Leperditia balthica Hisinger, var. guelphica Jones 



Page 106 



9 The largest valve observed. x2 

 10, 1 1 Two views of a valve, showing the eye tubercle distinctly. 

 X2. Both from the Guelph at Rochester 





