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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 
Fia. 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 ; ^ but in rare cases both the fore and hind feet may each 
1 American Journal of Science, vol. xliii. p. 344. 
