248 EXTINCT MONSTERS 



other times a second extra digit has been found, as well as those 

 above mentioned, which may be either smaller or larger. 



Coming now to the hind feet, we find that an extra toe may 

 sometimes be present on one or both of them, and always on the 

 inside. As a rule, however, these posterior toes are much smaller, 

 and often concealed beneath the skin. Fig. 91 is a drawing of a 



FIG. 91. Eight-toed Cuban horse. (After Marsh.) 



horse from Cuba, in which the extra toe is well developed on all 

 four limbs. This animal was examined by Professor Marsh during 

 its lifetime. 



Occasionally the hind feet have two extra toes, while the fore 

 feet have only one, as in the horse from Texas, figured by 

 Marsh ; l but in rare cases both the fore and hind feet may each 

 1 American Journal of Science, vol. xliii. p. 344. 



