PLATE XVI. 
EUOMPHALUS PLANODISCUS. 
Page 57. 
Pig. 1. The upper side of a specimen preserving the shell and surface-markings. 
Pig. 2. An enlargement of the same. 
Fig. 3. The same side of a larger specimen, showing a different character of surface. 
Pig. 4. A large internal cast, showing the size of the tube and comparative thickness of shell. 
Euomphalus (Strap arollus) inops. 
Page 58. 
Fig. 5. The umbilical side of the specimen. Prom Schoharie, 1ST. Y. 
Euomphalus (Strap arollus) uudis. 
Page 58. 
Pig. 6. The upper surface of a moderately large specimen, from which the shell has been partly removed. 
Pig. 7. The upper surface of a larger individual. 
Euomphalus (Phanerotintjs) laxus. 
Page 60. 
Pig. 8. A small specimen consisting of an entire volution. Prom the Hamilton group at Bellona, N. Y. 
Fig. 9. A larger specimen consisting of less than one volution. From the Hamilton group, Otsego county, N. Y. 
Fig. 17. A specimen of the species from Schoharie, N. Y. 
Fig. 18. A specimen preserving the inner volutions and imprint of the outer volution. 
Euomphaltjs (Straparollus) Hecale. 
Page 59. 
Pig. 10. The umbilical side, of a specimen of about the medium size, as obtained from a gutta-percha 
impression in the natural mold. From Meadville, Pa. 
Pigs. 11-14. A series of specimens showing the prevailing characters of the species as seen in this associa¬ 
tion, from western New York. 
Etjomphaltjs (Straparollus) clymenioides. 
Page 62. 
Fig. 15. A small specimen from the Schoharie grit. Schoharie, N. Y. 
Phanerotinus parodoxus, WinchelL* 
Page 60. 
Pig. 16. One of the specimens used by Mr. 'Winchell in the description of the species (taken from a cast). 
* This species, which I have compared with E. (P.) laxus, is certainly distinct from it. 
