CHARIONELLA, Bitttres. 
Page 775. 
CHARIONELLA scrTuLa, Billings. 
Fig. 12. Dorsal view of a specimen from which a portion of the shell has been 
removed exposing the muscular impressions of the brachial valve. 
Fig. 13. An internal cast of the pedicle-valve. 
Fig. 14. The cardinal portion of the brachial valve; showing the concave and 
adherent hinge-plate. x 3. 
Corniferous limestone. Cayuga, Ontario. 
PENTAGONIA, Cozzxns. 
Page 775. 
PENTAGONIA UNISsULCATA, Conrad. 
Figs. 15, 16, 17. Ventral, front and cardinal views of a normal example; 
showing the contour of the valves. 
Fig. 18. A preparation showing the form of one of the spiral cones and a por- 
tion of the jugum. 
Corniferous limestone. Western New York. 
Fig. 19. The interior of a pedicle-valve; showing the articulating apparatus 
and muscular scars. 
Fig. 20. The interior of a brachial valve; showing the articulating processes 
and short, low median septum. 
Corniferous limestone. Falls of the Ohio. 
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