xxv] 



CAKNIVORA 



675 



teeth reduced in number, the formula being i. ?, c . - t pm. -, 

 m. - = 30, whilst the fore-limbs can be used for seizing. The 



claws are very sharp, and can, when not in use, be completely 

 retracted or rather raised, so as not to wear the points. In all these 



19 a a 



FIG. 338. Vertical longitudinal section taken a little to the left of the middle 

 line through the skull of a Dog, Canis familiaris x . 



1. Supra-occipital. 2. InterparietaL 3. Parietal. 4. Frontal. 5. Cribri- 

 form plate. 6. Nasal. 7. Mesethmoid. 8. Maxilla. 9. Vomer. 

 10. Ethmoturbinal. 11. Maxilloturbinal. 12. Premaxilla. 13. Occip- 

 ital condyle. 14. Basi-occipital. 15. Tympanic bulla. 16. Basisphenoid. 

 17. Pterygoid. 18. Palatine. 19. Alisphenoid. 20. Internal auditory 

 meatus, the passage for the eighth nerve to the internal ear. 21. Tentorium, 

 a fold of calcified connective tissue projecting into the cranial cavity and 

 separating the cerebrum from the cerebellum. 22. Foramen lacerum 

 posterius, the passage for the tenth nerve. 23. Floccular fossa, 



the cavity in which the floccular lobe of the cerebellum is lodged. 

 24. Coronoid process. 25. Condyle. 26. Angle. 27. Mandibular 

 symphysis. 28. Inferior dental foramen. 29 31. Segments of the 

 second visceral arch. 29. Stylohyal. 30. Epihyal. 31. Cerato- 

 hyal. 32. Basihyal. 33. Thyrohyal, the third visceral arch, 



xii. Condylar foramen, the aperture through which the twelfth cranial 

 nerve leaves the skull. 



respects Cats are more perfectly adapted for a carnivorous life than 

 Dogs, since these latter still retain traces of their descent from a 

 different kind of Mammal. Just as the Wolf, C. lupus, the Jackal, 

 G. aureus, and the Fox, C. vulpes the last-named the only wild 

 species of Canis found in Britain are species of Dogs distinguished 

 from each other by size and slight peculiarities of hair, etc., so the 



432 



