THE EQUID^E, OR HORSES. 205 



nourished have been eliminated as ballast. They 

 are not yet quite cast off. The metatarsals, or 

 so-called ' splint bones,' are still attached to the 

 middle toe. The horse of the future will certainly 

 have cast off these rudiments, even though it may 

 take a few millions of years to accomplish this, 

 owing to the extraordinary perseverance with which 

 organisms drag about with them these useless in- 

 heritances. The Hipparion has not even yet 

 wholly disappeared from the scenes of life. 



Now and again horses have been met with, with 

 more than one toe, which must not rashly be 

 considered as a malformation ; it is simply a proof 

 of that repetition of or reversion to the original form 

 which in scientific language is called atavism. 

 This kind of Hipparion-horse, which is looked upon 

 by the common run of people as a curiosity and 

 monstrosity, has, as Siebold 1 has shown, been 

 repeatedly exhibited at horse-markets. The fol- 

 lowing is a description of an animal of this kind 

 given by Frank, Principal of the Veterinary College 

 of Surgery at Munich : * The so-called splint bones 

 (the metacarpals and metatarsals of the second 

 and fifth toes) are not reduced to the same extent. 

 On the fore-foot the mediale (M c 2) is the least 



1 Siebold, Hipparion auf JahrmtirMen. Miinchen, 1881. 



