534 



ZOOLOGY 



SECT. 



and structure from the molars. In the Horse (Fig. 1124) the 

 formula is- 



.314 3 



but the first premolar is a small tooth which soon becomes lost, 

 and may belong to the milk dentition. A fold of the enamel 

 dips downwards (i.e. towards the root) from the extremity of the 

 incisor teeth like the partly inverted finger of a glove : the 

 canines are small in the female, and may not appear on the sur- 

 face. There is a wide interval in both jaws between the canines 



Ncv 



MJC 



FIG. 1124. Side view of skull of Horse with the bone removed so as to expose the whole of the 

 teeth, c. canine ; q. y' 2 . i s . incisors ; m l . m%. m3. molars ; p. m 1 . situation of the vestigial 

 first pre-molar, which has been lost in the lower, but is present in the upper jaw ; pm' 2 .pm 3 .pn^. 

 remaining pre-molars ; //. frontal ; ju. jugal ; Icr. lacrymal ; max. maxilla ; <ia. nasal ; 

 pa. parietal ; par.oc. par-occipital process ; p.niax. pre_-maxilla ; oc. coml. occipital condyle ; 

 sq. squamosal. (After Flower and Lydekker.) 



and pre-molars. The pre-molar and molar teeth present a com- 

 plicated pattern due to folds of the enamel, which differ in their 

 arrangement in the upper and lower jaws ; their roots become 

 completed only at a late period. 



In the Hyracoidea the dental formula is- 



1043 



The upper incisors are not unlike the larger pair of the Rabbit in 

 shape, though prismatic and pointed, instead of compressed and 

 chisel-like, and grow from persistent pulps. The outer incisors 

 are elongated, inclined forwards, and trilobed at the extremities. 



