CRYPTONELLA, Hatt. 
Page 860. 
CRrYPTONELLA Eximia, Hall. 
Fig. 16. An enlargement of the umbonal portion of the valves; showing the 
deltaria. 3. 
Lower Helderberg group. The Helderbergs, N. Y. 
CRYPTONELLA RECTIROSTRA, Hall. 
Figs. 17, 18. Dorsal and profile views of a small example. 
Hamilton shales. Canandaigua Lake, N. Y. 
CRYPTONELLA PLANIROSTRA, Hatt. 
Figs. 19, 20. Dorsal and ventral views of an internal cast; showing the muscu- 
Jar impressions and vascular sinuses. 
Hamilton group. Hardy county, Virginia. 
Fig. 21. An enlargement of the cardinal portion of the pedicle-valve; showing 
the foramen, deltidial plates and teeth. 
Hamilton group. Moscow, N. Y. 
Figs. 22, 23. Dorsal and profile views of a normal adult. 
Hamilton group. Western New York. 
EUNELLA, Hatt. 
Page 861. 
EuNELLA simuLATOR, Hall. 
Fig. 24, Dorsal view of a specimen which has been cut to show the loop, the 
recurved branch of which is not retained. 2. 
Hamilton group. Thedford, Ontario. 
= Eonetyia Suttivantt, Hall. 
Figs. 6, 28, Dorsal and profile views of the original specimen. 
' \ Corniferous limestone. Columbus, Ohio. 
0,3) Eunexia Lincexant, Hall. 
Figs. 27, 28. Dorsal and profile views of a mature shell. 
Hamilton group. Canandaigua Lake, N. Y. 
HARTTINA, Hatt. 
Page 862. 
Hartrina Anna, Hartt. 
Figs. 29, 30, 81. Dorsal, profile and ventral views of a well-preserved example; 
showing the subplano-convex contour of the valves. 
Carboniferous limestone. Windsor, Nova Scotia, 
263 
