CHAP. II.] 



THE CAT'S GENERAL FORM. 



27 



The mucous membrane is connected with the subjacent parts by 

 submucous areolar tissue, which is often lax, so that the mucous 

 membrane, when not stretched, is thrown into effaceable folds or 

 rugae. It may also form folds which are not to be effaced by any 

 stretching of the skin, as, e.g., on the palate (Fig. 86). 



The membrane lining the mouth abounds in small glands, 

 those within the cheeks and lips being termed buccal and labial 

 respectively. 



16. The mucous membrane of the mouth has certain calcareous 

 appendages the TEETH which are mainly calcifications of the 

 corium, but in part are ecteronic or calcifications of the epithelium 

 so that the nature of each is compound. 



The teeth are not only parts of the external skeleton, but are 





FIG. 12. THE TEETH OF THE RIGHT SIDE OF A. CAT'S MOUTH, SEEN ON THEIR INNER SURFACES. 



Incisors. 

 . Canines. 

 prn. Premolars. 



t of the teeth 



m. Two molars. (The outer aspect of the tc 

 is shown in Fig. 40. See also Fig. 29.) , 



closely related to the internal skeleton also, since they are implanted 

 in special sockets or alveoli provided for them in the margins of 

 the jawbones, which margins are on that account spoken of as 

 " alveolar." The part of each tooth which is thus implanted is its 

 " fang." The part which appears above the surface of the mucous 

 membrane is called the "crown," and the line of junction is ^ the 

 cervix, or neck. Each alveolus closely invests the fang contained 

 within it. Most of the teeth have but a single fang, which tapers 

 as it penetrates its alveolus ; but there may be two or three fangs to 

 a single tooth. . , 



The teeth of the cat, when adult, should be thirty in number. 

 Those of the two sides of each jaw are alike, but those of the upper 

 iaw differ from those of the lower jaw. 



The three front teeth of each lateral half of the upper jaw are 

 very small and simple in'shape. They stand side by side, so that 



