CHAP. XIII.] 



THE CAT'S PLACE IN NATURE. 



477 



it, emerges at the foramen lacerum anterius (just within and 

 behind the opening of the Eustachian canal), and bending round 

 re-enters the skull, in a backward direction, at the same foramen. 

 The paroceipital process (p) is somewhat triangular, and projects 

 downwards, outwards and backwards, standing quite aloof from the 

 bulla. The mastoid process {di) is widely separated from the par- 

 occipital, and is more or less prominent. The condyloid foramen (c) 

 can be plainly seen, and is not sunk into a common opening with 

 the foramen lacerum posterius. A foramen which gives exit to a 

 vein — the foramen glenoideum (g) — is conspicuous Justin front of the 

 meatus auditorius externus. A large canal is formed by the ali- 

 sphenoid, which throws out a lamina of bone to embrace the external 

 carotid artery. The passage thus enclosed is (as has been before 



Fig. 194. — Vertical Section through Tympanic Cvvity of Bear (Flower). 



am. Meatus aurtitorius externus. 

 BO. Basi-oceiiiital. 

 Car. Carotid canal. 

 e. Eustachian canal. 



(I. Glenoirl canal leading to glenoid foramen. 

 S'l. Si[uaniosal. 

 T. Tympaiiic bone. 

 t. Tympanic ring. 



mentioned) called the aUsphenoid canal. Its posterior aperture {a) 

 is its own exclusively, but its anterior opening {a) includes within 

 it that of the foramen rotundum. 



"When the auditory bulla is seen in section (Fig. 194), the simplicity 

 of its cavity is apparent. 



The above-given cranial characters are, with the exception of that 

 of the presence of an alisphenoid canal and of the emergence 

 anteriorly of the internal carotid artery, characters of the whole of 

 the Arctoidea,* and to them may be added the further distinctions, 

 that there is no caecum whatever to the intestinal canal ; that the 

 penis contains a large bone, which is not grooved, but which is dilated 



* Certain exceptional details are presented by Ailiirojms. 



