146 



Report of the State Geologist. 



PLATE II. 



Manticoceras Pattersoni, Hall (sp.). 



(See Plates I and IV.) 



Figure 1. A transverse section of a small specimen showing marked irregu- 

 larity, for a short period, in the depth of the septal chambers. 



Figure 2. A shell with ephebic suture, retaining a rather strong surface 

 ornament. 



Figure 3. The protoconch, nepionic shell and a portion of later growth 

 much enlarged. 



Naples beds, Naples. 



Figure 4. Internal cast of ephebic shell. 



Naples beds, Honeoye lake. 



Manticoceras oxy, sp. nov. 



(See Plate III.) 



Figure 5. A rather small ephebic specimen with extreme Pattersoni sutures. 



Figure 6. Front view of the same, to show the sharply carinate venter. 

 Lower Portage falls of the Genesee river. 



