Explanations of Plates. 



215 



Hydnocekas LuTiiEiii, sp. nov. 



Page 106. 



Figure 7. A young and slender specimen with low nodes. 



Figure 8. An entire individual with three well developed rows of nodes and 



entire aperture. 

 Figure 9. A mature individual with four horizontal rows of nodes. 

 Figure 10. A full-grown exainple with strong nodes in three rows and an 



accessory node in the apertural region. 



Chemung group. 8egur''s gully, Italy, Yates county, New YorJc. 



