vi STUDIES IN THE EVOLUTION OF ANIMALS 



PAGE 



Part x— Explanation of the Callosities on the Legs of Equine Animals 



and others, 229 



,, XL— The One Big Digit of the Horse, 241 



„ XII. — Monstrosities as probable factors in the creation of species, . 273 



General Conclusions, 325 



Appendices, 33' 



