428 MAMMALIAN ANATOMY 



Posterior fang- large, prismatic ; 

 anterior cingular cusp absent or 



obscure Second upper premolar. 



Fangs subequal, well marked ante- 

 rior cusp. 

 Smaller tooth, secondary cusps 



less marked First lower premolar. 



Larger tooth, secondary cusps 



well developed Second lower premolar. 



Teeth with crowns narrowed to cutting blades. 



Three fangs Third upper premolar. 



Two fangs Lower molar. 



Small tooth with transverse, flat, tubercular 



crown and two variable transverse fangs . Upper molar. 



VARIATIONS IN THE TEETH. 



The abnormalities of the teeth may be classified as : 



(1) Variations in size, shown in the crown or in the number of 

 fangs. 



(2) Variations in number, shown in the absence of a tooth or by 

 supernumerary teeth. 



(3) Variations in form, due to a malformation which may be 

 single, as confined to one tooth, or double, by the fusion of two teeth. 



(4) Variations in position of the teeth in the jaws. 



More than one kind of variation may be shown by a single tooth, 

 or several teeth in the same jaw may be' abnormal either in the same 

 direction or differently. 



In the following paragraphs I have arranged the variations of each 

 tooth by themselves, and have included the observations of Hensel 1 

 and Bateson. 2 



Incisor Teeth. No variations have been observed in the incisors 

 of the cat ; they probably exist, inasmuch as Bateson records the 

 occurrence of two extra upper premaxillary teeth in a specimen of 

 Felis lynx, and an absence of at least one incisor in several other 

 species. 



Canine Teeth. The canines appear to be constant. I have seen 



1 Morpbologisches Jahrbuch, 1879, v. p. 552. 



2 Materials for the Study of Variation, 1894, pp. 223-226. 



