558 NEW YORK STATE MUSEUM 



Protocycloceras lamarcki Billings (sp.) 



Page 441 

 See pi. 16, fig. I, 2 



1 Fragment with narrow annulated and relatively wide interspaces. 

 Drawn from a gutta-percha squeeze 



2, 3 Two views of a specimen retaining in part the wall and show- 

 ing the position and relative size of the siphuncle 



4 Natural section of a specimen. The septa are slightly curved in 



the original. 



5 Specimen showing a slight curvature of the conch and a more 



central position of the siphuncle in the section than the original 

 of figure 3. 



6 A longitudinally striated fragment of a conch, found associated 



with this species and presumably representing the apical part of 

 the same. Drawn from a gutta-percha squeeze 

 The originals of figures i and 6 are from the Beekmantown beds of 

 the Spelman ledge at Beekmantown; those of figures 2-5 from 

 the Fort Cassin beds at Valcour, figures 2, 3, 4 from A3 of the 

 section, figure 5 from A.-. Originals are now in the New York 

 State Museum. 



Protocycloceras w^hitfieldi sp. nov. 



Page 443 



7 The type of the species. A section of the same is reproduced in 



text figure 17. 

 The original is from the Fort Cassin beds at Fort Cassin and now 

 in the museum of Burlington University. 



