PLATE XVII. 
Fig, Page 
1. Mesodon sp.; vomerine dentition.—Great Oolite; Caen. 
[40353.] 212 
2. Athrodon sp. ; vomerine dentition.—Portland Stone; near 
Weymouth. [P. 7186.] 217 
3. Microdon hugii (Agassiz) ; left splenial dentition.™Ibid. 
[30871.] 229 
4. Gyrodus planidens , sp, nov.; vomerine dentition.—Kim- 
meridge Clay; Weymouth. [P. 3785 b.] 244 
5. Vomerine dentition of undetermined Pycnodont.—Ibid. 
[43285.] 245 
6. Aspidorhynchus euodus, Egerton ; skull, lateral aspect.™ 
Oxford Clay ; Christian Malford. ecpt. Ectopterygoid. 
enpt. Entopterygoid. na. Narial opening, pas. Para- 
sphenoid. pi. Palatine, pmx. Premaxilla, pt. Post¬ 
temporal. qu. Quadrate. [40518.] 423 
7. Ditto ; imperfect fractured skull, the hinder portion ex¬ 
posed from above, the rostrum from below.—Ibid. fr. 
Frontal, pa. Parietal, pas. Parasphenoid. pf. Pre¬ 
frontal. pmx. Premaxilla, sq. Squamosal, v. Vomer. 
[29042.] 424 
8. Ditto ; Maxilla.—Ibid. [29045 a.] 425 
9. Ditto; right Dentary.—-Ibid. [41296.] 425 
10. Ditto; Splenial. [29047.] 425 
11. Aspidorhynchus crassus , A. S. Woodward; presymphysial 
bone.—Stonesfield Slate; Stonesfield. [P. 3720 g.] 427 
12. Belonostomus tenuirostris, Agassiz ; head, lateral aspect.— 
Lower Kimmeridgian; Solenhofen. d. Dentary. ps. 
Presymphysial bone. [35014.] 432 
