number of the teeth is very generally forty-four, while in the horse the usual number is forty, and, in the absence of the canines, it may be reduced to thirty-six; the incisor teeth are devoid of the fold seen in those of the horse; the grinders regularly diminish in size from the middle of the series to its front end; while their crowns are short, early attain their full length, and exhibit simple ridges or tubercles, in place of the complex foldings of the horse’s grinders.

      “Hence the general principles of the hypothesis of evolution
     lead to the conclusion that the horse must have been derived from
     some quadruped which possessed five complete digits on each foot;
     which had the bones of the forearm and of the leg complete and
     separate; and which possessed forty-four teeth, among which the
     crown of the incisors and grinders had a simple structure; while
     the latter gradually increased in size from before backwards, at
     any rate in the anterior part of the series, and had short
     crowns.

      “And if the horse had been thus evolved, and the remains of the
     different stages of its evolution have been preserved, they ought
     to present us with a series of forms in which the number of the
     digits becomes reduced; the bones of the forearm and leg
     gradually take on the equine condition; and the form and
     arrangement of the teeth successively approximate to those which
     obtain in existing horses.

      “Let us turn to the facts and see how far they fulfill these
     requirements of the doctrine of evolution.

      “In Europe abundant remains of horses are found in the
     Quaternary and later Tertiary strata as far as the Pliocene
     formation.  But these horses, which are so common in the
     cave-deposits and in the gravel of Europe, are in all essential
     respects like existing horses, and that is true of all the horses
     of the later part of the Pliocene epoch.  But, in the deposits
     which belong to the earlier Pliocene, and later Miocene epochs,
     and which occur in Britain, in France, in Germany, in Greece, in
     India, we find animals which are extremely like horses—­which in
     fact are so similar to horses, that you may follow descriptions
     given in works upon the anatomy of the horse, upon the skeletons
     of these animals—­but which differ in some important particulars. 
     For example, the structure of their fore and hind limbs is
     somewhat different.  The bones, which, in the horse are
     represented by two long splints, imperfect below, are as long as
     the middle metacarpal and metatarsal bones; and, attached to the
     extremity of each, is a digit with three joints of the same
     general character as those of the middle digit, only very much
     smaller.  These