56 
CHOOEROIDEl. 
This may be regarded as the type species of the genus as here 
defined. 
Form. Sf Loc. Bathonian (Stonesfield Slate): Stonesfield, Oxford¬ 
shire. 
P. 486. Bight mandibular tooth, inner aspect, to be regarded as the 
type specimen ; figured by Agassiz, tom. cit. pi. xl. fig. 7. 
Egerton Coll. 
P. 3100, P. 3105 a. Two left mandibular teeth, exhibiting the inner 
aspect, labelled by Agassiz. Enniskillen Coll. 
36584. Broken left mandibular tooth, inner aspect. 
Purchased , 1862. 
P. 5108. Left mandibular tooth, outer aspect. 
Presented by J. E. Lee , Esq., 1885. 
P. 485. Bight palatine tooth, exhibiting only the superior aspect, 
figured by Agassiz, tom. cit. pi. xl. fig. 6. Egerton Coll. 
P. 1133. Left palatine tooth, oral aspect, figured in Proc. Geol. Assoc. 
vol. xi. pi. iii. fig. 4. Egerton Coll. 
P. 3100 b, C. Two similar left palatine teeth, one being shown, of the 
natural size, in PI. I. fig. 9. The oral aspect not being 
exposed in no. P. 485, these two specimens, with no. 
P. 1133, cannot be precisely compared, but their identity 
is probable and one is labelled “ Chimcera oiuenii, Buckl.,” 
in Agassiz’s handwriting. Enniskillen Coll. 
P. 3100 a. Bight vomerine tooth, resembling that of Ischyodus in 
form, and labelled by Agassiz as pertaining to this species. 
Enniskillen Coil. 
Two “species ” of Ganodus — G. falcatus, Egerton 1 , and G.jysittci- 
cinus, Egerton 2 —have also been founded upon mandibular teeth 
exhibiting the external aspect, and are not yet distinguishable with 
certainty from G. oiveni. Both type specimens were obtained from 
the Stonesfield Slate, and are contained in the Egerton Collection. 
Of the left mandibular tooth described and figured as G. falccitus 
(P. 482), it is not improbable that the form of the oral margin and 
the prominence of the beak are due to accident; and, though 
1 Quart. Journ. Geol. Soc. vol. iii. (1847), p. 352. Chimcera fcdcata, Proc. 
Geol. Soc. vol. iv. (1843), p. 154. Ischyodus falccitus, Sir P. Egerton, ibid. 1843, 
p. 156. Chimcera {Psittacoclon) fcdcata, L. Agassiz, Poiss. Foss. vol. iii. (1843), 
p. 349, pi. xl. c. fig. 13. 
2 Quart. Journ. Geol. Soc. vol. iii. (1847), p. 352. Chimcera psittacina, Proc. 
Geol. Soc. vol. iv. (1843), p. 153. Ischyodus psittcicinus, Sir P. Egerton, ibid. 
1843, p. 156. Chimcera {Psittacodon) psittacina, L. Agassiz, Poiss. Foss. vol. iii. 
(1843), p. 350, pi. xl. c. fig. 12. 
