168 ANIMALS OF THE PAST 
even the suggestion of a fourth toe. From 
this to our Eocene Hyracothere with four toes 
is only another long-time step. We may go 
even beyond this in time and structure, and 
carry back the line of the horse to animals 
Hae 
press ptt 
Ba a (ros 
SUPPOSED TYPE UNDISCOV- PROTOROHIPPUS MESOHIPPUS MESOHIPPUS 
“ERED ANCESTOR VENTICOLUS. COPE BAIRDII, LEIDY PRAESTANS. COPE 
Fig. 34. The Development 
which only remotely resembled him and had 
five good toes to a foot ; but while these con- 
tained the possibility of a horse, they made n¢ 
show of it. 
Increase in size and decrease in number 0 
