PLATE LIX. 
I 
(Figs. 1-12, 18-22, 26, 30, 31, 37, 38 by R. P. WHITFIELD; 13, 14, 24, 25, 28, 29, 32, 33 by E. Emmons; 15-17, 23, 27, 34-36 
by G. B. Simpson.) 
Genus LIORHYNCHUS, Hall. 
Page 193. 
Liorhynchus limitaris, Viinuxeni. 
Figs. 1, 2. Dorsal and frontal views of a small individual. 
Marcellus shales (Goniatite limestone). Schoharie county, N. Y. 
Figs. 3-5. Frontal, cardinal and ventral views of a larger specimen. 
Limestone of the Marcellus shales, Avon, N. Y. 
Liorhynchus dubius, Hall. 
Figs. 6, 7. Ventral and dorsal views of a typical specimen. 
Marcellus shales. Locality ? 
Liorhynchus multicosta, Hall. 
Fig. 8. The exterior of a pedicle-valve of an elongate specimen, the regular growth of which has been 
interrujited in the umbonal region. 
Fig. 9. The brachial valve of a more orbicular and typical shell. 
Fig. 10. A cardinal view ; showing the convexity of the (valves. 
Hamilton group. Western New York. 
Liorhynchus mesacostalis, Hall. 
Fig. 11. The exterior of the pedicle-valve ; showing the inequal plication of the sinus. 
Fig. 12. An internal cast of a large brachial valve; showing the position of the median septum, the elon¬ 
gate muscular scars and the absence of plications on the lateral slopes. 
Chemung group. Tompkins county, N. Y. 
Liorhynchus Laura, Billings. 
Figs. 13, 14. Ventral and dorsal views of a rather elongate individual. 
Fig. 15. Posterior view of the hinge-plate and crura; showing the great elevation of the latter and their 
basal expansions. X 4. 
Fig. 16. The same specimen, viewed from above ; showing the narrow, submarginal dental sockets, the 
broad triangular divisions of the hinge-plate, the median septum and the recurvature of the 
long crura. X 4. 
Fig. 17. The interior of the umbonal portion of the pedicle-valve ; showing the open delthyrium, small 
teeth and faint muscular impression. 
Hamilton group. Widder, Ontario. 
Liorhynchus Kellogqi, Hall. 
Fig. 18. Cardinal view of an internal cast; showing the cavities left by the dental plates, median septum 
and crura. 
Figs. 19, 20. Dorsal and ventral views of a normal adult; showing the obsolescence of plications except 
upon fold and sinus. ^ 
Hamilton group. Northen’n Ohio. 
Liorhynchus quadricostatus, Vanuxeni. 
Fig, 21. View of a crushed and somewhat distorted jiedicle-valve of large size; showing the character of 
the plication. 
Fig. 22, A small internal cast of the brachial valve in which the lateral plications are obsolete. 
