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13 shows the dorsal side of Fig. II on the paranepionic whorl inside of umbilical 

 perforation and just before the apex is reached. This has sutures with dorsal 

 lobes and is flattened as is shown in section of the same, Fig. 14 ; this flattening 

 also occurs in the paranepionic whorl of Fig 6. 



Figs. 15-17. Aphetoceras boreale, Hyatt, Quebec Group; Loc, Schooner's 

 Island, Newfoundland. Fig. 15, side view, and Figs. 16 and 17, sections all one- 

 third reduced, showing form and absence of impressed zone. For other species of 

 this genus see PI. vi. 



Figs. 18-20. Pycnoceras apertutn, Hyatt, Quebec Group; Loc, Port au Port, 

 Newfoundland. Fig. 18, side view, reduced one third, with apex restored. Fig. 

 19, view of venter of same encrusted with dorsal shell of older volution, the 

 remainder of this volution having been destroyed by erosion. This shell shows 

 the contact furrow and the dorsal lobes in the sutures of older stages. Fig. 20, 

 view of the part of the nepionic whorl of Fig. 18, enlarged 2 diameters, showing 

 the absence of dorsal furrow and the form of the metanepionic and paranepionic 

 substages of this species. The remnants of the dorsal shell described above are 

 omitted in this figure and in Fig. 18. 



