i6o 



FIG. 



I, 2 



3.4 



7,8 



NEW YORK STATE MUSEUM 

 PLATE io 



Poleumita (?) sulcata Hall (sp.) 



Page 62 



Two views of a typical specimen. Natural size 

 Profile and umbilical views of another specimen. Natural size. 

 Rochester (Arey collection) 



Trochonema cf. fatuum Hall 



Page 75 



Lateral view of the only specimen observed. Natural size. 

 Upper Shelby bed (N. Y. State Museum) 



Lophospira bispiralis Hall (sp.) 



Page 71 



Apical part of a specimen, showing distinctly the carinae. 



From a gutta-percha impression of a natural mold. X2. 



Lower Shelby bed (N. Y. State Museum) 

 Two older individuals which show the structure of the slit 



band and the gradual obsolescence of the carina on the 



upper side of the volution. Natural size. Rochester 



