226 THE VISCERA. 
jaw is small and lies caudomediad of the last premolar. It has 
two small cusps and two fangs. 
Fic. 94.—MANDIBLE, WITH ROOTS OF THE TEETH LAID BARE. 
@, incisors; 4, canine; ¢, first premolar; d, second premolar; /, molar. - 
In the lower jaw (Fig. 94) the two premolars (¢ and @) are 
similar, the caudal one being a little larger. Each has four 
cusps; a single large one, a small one craniad of this, and two 
small ones ‘caudad of it. Each has two fangs. The single 
molar (/) is the largest tooth of the lower jaw; it has two large 
cusps and two fangs. 
The Deciduous Teeth.—At birth the cat has no teeth. 
There appears later a set of twenty-six teeth: twelve incisors, 
four canines, and ten molars (six in the upper jaw and four in 
the lower). These teeth are later replaced by the permanent 
ones above described. The deciduous teeth of the cat are fully 
described by Jayne (‘‘ Mammalian Anatomy,’’ vol. I. p. 319), 
where also an account is given of the order of appearance of 
the teeth. 
THE TONGUE. LINGUA (Fig. 95).—The tongue is a 
muscular organ covered with mucous membrane; in life it is 
very mobile. It is an elongated organ, flat above, broadest in 
the middle, and very slightly narrowed at each end. It 
extends from the incisor teeth to the isthmus faucium and 
nearly fills the mouth cavity: The caudal third of the tongue 
forms the floor of the mouth cavity, so that the tongue has here 
no ventral surface, but is directly continuous with underlying 
organs. It is in this region that the extrinsic muscles of the 
tongue (except the genioglossus) enter it. The cranial two- 
thirds of the tongue is partly or entirely free from the floor of 
the mouth, the cranial one-third being completely free and 
movable. In about the middle third the ventral surface of the 
