PLATE XXX. 
PAGE 
Figs, la, lb. Odontaspis cuspidata ( Agassiz) 78 
la. Outer face of a tooth showing a rudimentary second pair of 
lateral denticles. St. Mary's River. x 4/3 
lb. Inner face of the same specimen. x 4/3 
Pigs. 2a, 2b, 3. Odontaspis elegans (Agassiz) 79 
2a. Outer face of a small tooth. Plum Point. x 4/3 
2b. Inner face of the same specimen. X 4/3 
3. Outer face of a somewhat worn tooth, the lateral denticles broken 
away. Plum Point. 
Fig. 4. OxYRHiNA DESOKii Agasslz 79 
4. Inner face of a moderate-sized tooth. Charles County near the 
Patuxent River. Acad. Nat. Sci., Phila. 
Figs. 5a-6c. Oxyrhina hastalis Agassiz 80 
5a. Inner face of a medium-sized and somewhat worn specimen. 
Flag Pond. 
5b. Outer face of the same specimen. 
6a. Outer face of a large-sized lateral tooth. Jones Wharf. 
Gb. Profile of the same specimen. 
6c. Inner face of the same specimen. 
Fig. 7. Oxyrhina sillimani Gibbes 81 
7. Outer face of an average-sized tooth. Fairhaven. 
Figs. 8, 9. Otodus obliquus Agassiz 82 
8. Inner face of a small-sized specimen with erect crown. Charles 
County near the Patuxent River. Acad. Nat. Sci., Phila. 
9. Inner face of a small-sized lateral tooth with oblique crown. 
Charles County near the Patuxent River. Acad. Nat. Sci., 
Phila. 
