CiiAr. III. 



THEIR VARIATION. 



75 



and various other modifications, as Nathusius observes, can 

 hardly be considered as monstrosities, for they are not in- 

 jurious, and are strictly inherited. The whole head is much 

 shortened ■ thus, whilst in common breeds its length to that 

 of the body is as 1 to 6, 

 in the " cultur-racgn " 

 the proportion is as 1 

 to 9, and even recently 

 as 1 to ll. 15 The fol- 

 lowing woodcut 16 of the 

 head of a wild boar and 

 of a sow from a photo- 

 graph of the Yorkshire 

 Large Breed, may aid 

 in showing how greatly 

 the head in a highly 

 cultivated race has been 

 modified and shortened. 

 Nathusius has well 

 discussed the causes of 

 the remarkable changes 

 in the skull and shape 

 of the body which the 

 highly cultivated races 

 have undergone. These 

 modifications occur 

 chiefly in the pure and 

 crossed races of the S. 

 indicus type ; but their 

 commencement may 

 be clearly detected in 

 the slightly improved 

 breeds of the S. scrofa 

 type. 17 Nathusius states 

 positively (s. 99, 103), 

 as the result of common experience and of his experiments, 



15 l Die Raeen des Schweines,' s. 70 excellent edition of ' The Pig,' by 



16 These woodmts are copied from Youatt, 1860. See pp. 1, 16, 19. 

 engravings given in Mr. S. Sidney's lT ' Schweineschadel,' s. 74, 135. 



Head of Wild Roar, and of "Gold'n Days,'' a 

 pisr of the York hire La'ge Breed; the latter fr. m a 

 T'ho'osraph.. (Copied fioui Sidney's edit, of 'The 

 Pig,' by Youa.t.) 



