Chap. II. THEIK VARIATION. 53 



which the projections were between three and four inches in 

 length : other instances have occurred in Spain. 



That there has been much inherited variation in the horse 

 cannot be doubted, when we reflect on the number of the 

 breeds existing throughout the world or even within the 

 same country, and when we know that they have largely 

 increased in number since the earliest known records. 10 Even 

 in so fleeting a character as colour, Hofacker n found that, 

 out of 216 cases in which horses of the same colour were 

 paired, only eleven pairs produced foals of a quite different 

 colour. As Professor Low 12 has remarked, the English race- 

 horse offers the best possible evidence of inheritance. The 

 pedigree of a race-horse is of more value in judging of its 

 probable success than its appearance : " King Herod " gained 

 in prizes 201,50bl. sterling, and begot 497 winners ; " Eclipse "' 

 begot 334 winners. 



Whether the whole amount of difference between ihe 

 various breeds has arisen under domestication is doubtful. 

 From the fertility of the most distinct breeds 13 when crossed, 

 naturalists have generally looked at all the breeds as having 

 descended from a single species. Few will agree with 

 Colonel H. Smith, who believes that they have descended 

 from no less than five primitive and differently coloured 

 stocks. 14 But as several species and varieties of the horse 

 existed 15 during the later tertiary periods, and as Kutimeyer 

 found differences in the size and form of the skull in the 

 earliest known domesticated horses, 16 we ought not to feel 

 sure that all our breeds are descended from a single species. 



10 Godron, ' De PEspece,' torn. i. tendency has been more carefully 

 p. 378. observed. 



11 ' Ueber die Eigenschaften,' &c, 13 Andrew Knight crossed breeds so 

 1828, s. 10. different in size as a dray-horse and 



12 ' Domesticated Animals of the Norwegian pony : see A. Walker on 

 British Islands,' pp. 527, 532. In all ' Intermarriage,' 1838, p. 205. 



the veterinary treatises and papers u ' Nat. Library, Horses,' vol. xii. 



which I have read, the writers insist p. 208. 



in the strongest terms on the inherit- 15 Gervais, 'Hist. Nat Mamm., 



ance by the horse of all good and bad torn. ii. p. 143. Owen, ' British Fossil 



tendencies and qualities. Perhaps the Mammals,' p. 383. 



principle of inheritance is not really 16 ' Kenntniss der fossil«n Pferde, 



stronger in the horse than in any other 1863, s. 131. 



animal ; but, from its value, the 



