Permanence and Evolution. , 35 



THE Ass. 



There is less diversity of appearance in the 

 ass than in the horse. In some countries there 

 are well-marked breeds ; of the origin of these 

 breeds nothing is known. Of the existing known 

 wild asses only one (A tceniopus of Abyssinia) 

 bears any close resemblance to any domestic 

 ass, but it does not follow that it is the sole 

 origin of all breeds ; in fact it seems (see " Blyth 

 Field," vol. xxxviii. p. 51) that there are now 

 in existence undescribed wild forms. The asses 

 with extra markings are probably derived from, 

 or crossed with, some form resembling in colour 

 the zebras. 



THE HOG. 



As in so many similar cases, it used to be 

 supposed that all domestic pigs had one origin, 

 the wild boar of Europe. Pallas first insisted 

 that the East Asiatic hog (called by him Sus 



