PLATE IV. 



PAGE. 



Fig. 1-3. Cladodus euglyphrus, St. J. and W 274 



1 a. View of anterior face of minute tooth, enlarged ; 1 b, base from below. St. Louis 



limestone; Alton, Illinois. 



2 a. Outer face of medium-sized tooth, enlarged ; 2 b, view of base from below. Same hori- 



zon; St. Louis. Missouri. 



3 a. Outer face of large tooth, enlarged two diameters ; 3 b, view of posterior face ; 3 o, base 



from below; 3 d, profile section. St. Louis beds ; Pella, Iowa. 



Fig. 4. Cladodus ecce st uicus, St. J. and VV 272 



4 a. View of outer face of medium-sized tooth, enlarged two diameters ; 4 b, inferior basal 



surface; 4 c, profile section. St. Louis limestone ; St. Louis, Missouri. 

 Fig. 5. Cladodus Van Hokxfi. St. J. and TV" 273 



5 a. Outer face of medium-sized perfect tooth, 5 b, posterior face; 5 c, inferior basal sur- 



face; 5 d, profile section. St. Louis limestone; Alton, Illinois 

 Fig. 6,7, Clauodus Caiunatus, St. J. and TV 279 



6 a. View of outer face of minute tooth, enlarged ; C b, base from below ; 6 c, profile sec- 



tion. Middle Coal Measures; Guthrie county, Iowa. 



7 a. Outer face of large symmetrical tooth, enlarged ; 7 b, outline of base from below. Coal 



Measures, Girard, Illinois. 



Fig. 8. Clauodus paxpatus, St. J. and TV 278 



S a. View of outer face, enlarged four diameters ; 8 b, postero -superior basal aspect j 8 c, 

 inferior basal surface ; 8 d, profile section. Coal Measures ; Carlinville, Illinois. 



Fig. 9. Clauodus Fulleri, St. J. and TV 276 



9 a. Outer face of minute tooth probably referable to this species, enlarged four diameters; 

 9 b, posterior face; 9 c, base from below; 9 d, profile section. Middle Coal Meas- 

 ures; Iowa. 



Cladodus lelltfer, St. J. and TV 270 



View of outer face of large tooth-; 10 6, posterior face ; 10 c, profile view ; 10 d, base 

 from below. Upper Burlington limestone; Louisa county Iowa. 



Cladodus intekcostatus, St. J. and TV 267 



Outer face of tooth, enlarged two diameters; 11 b, posterior face; 11 c, base from below,- 

 11 d, profile section. Upper Purington ; Louisa county, Iowa. 



Cladodus gomphoides, St. J", and TV 269 



Outer face of small tooth j 12 b, posterior face ; 12 c, base from below ; 12 d, profile sec- 

 tion. Upper Burlington, Louisa county, Iowa. 



13 a. Outer face of minute tooth, enlarged; 13 b, base from below. Same horizon and 



locality. 



14 a. Outer face of medium-sized, imperfect tooth. Same horizon and locality. 



15 a. Outer face of tooth, showing but one denticle either side of median cone; 15 b, poste- 



rior face ; 15 c, profile section. Same horizon and locality. 



16 a Outer face of laige, less symmetrical tooth ; 16 b, profile section. Same horizon and 



locality. 

 Fig. 17. Cladodus pkjbnuntius, St. J. and "W" 270 



17 a View of outer face of nearly perfect tooth ; 17 b, posterior- face ; 17 c, -view of inferior 



basal surface. Upper Burlington ; Louisa county, Iowa. 

 Fig. 18. Cladodus raeicostatus, St. J. and TV 271 



18 a. View of outer face of tooth ; 18 b, profile section. Keokuk limestone. 



rig. 



10. 





10 a. 



Fig. 



11. 





11 a. 



Fig. 



12-16. 





12 a 



