MERISTIC VARIATION 



6l 



More rare than this are : (i) the development of iv, making an extra 

 toe on the outside ; (2) development of n and iv, with in normal, making 

 three toes in all, after the fashion of the protohippus ; and (3) development 

 of ii and iv with in aborted, resulting in an abnormal two-toed foot. All 

 these forms are well known among horses. 



4. Horse with supernumerary on outside of each fore foot, illustrating 

 condition mentioned above (development of digit iv) (see Fig. 12). 



5. Horse with both splint bones 

 bearing digits on each foot, illustrat- 

 ing condition 2 (n and iv developed 

 normal, making a three-toed horse). 



FIG. ii. Right fore foot of horse (front 

 view) : as the hoof of the horse is re- 

 garded as digit in, this extra member 

 is to be considered as digit ii. After 

 Bateson 



FIG. 12. Right fore foot of horse 

 (rear view) : this extra toe is to 

 be regarded not as digit ii but 

 as digit iv. After Bateson 



