86 



form of all the present ungulates, and therefore, of the Horse. It 

 was associated with a form already shown —the Goryplwdon and 

 also with another, — the Hyracotheriuni. Its own name is Phena- 

 co'lm ; in size it was somewhat larger than a sheep, and possessed 

 five hoofed toes on each foot, though possibly only three were used 

 in walking ; its brain was very small. Its restored form is shown 

 on the next slide. 



We have now got as far back as we can get in our researches at 

 present, though of course the Phenacodus itself, on our theory, must 

 have had ancestors. From this very generalized form, we are 

 taught, different genera and species of hoofed animals were 

 developed along various lines, according as variations in their own 

 structure fell into harmony with the physical conditions by which 

 they were environed. As one geographical change succeeded 

 another, those forms which, by virtue of some fortunate variation 

 in their structure, were able to accommodate themselves to the 

 new conditions, survived and flourished ; all who could not do this 

 perished, and such must have been the case with immense numbers. 

 There is a little uncertainty still prevalent as to whether the 

 development of our Horse took place in the Old World, or in the 

 New. Did we receive our horses from America, or did some of our 

 early forms find their way over there ? Probably there were 

 developments in both continents. The Phenacodus however, has 

 not yet been discovered on this side of the Atlantic. In those 

 same old lake deposits of the Eocky Mountain district occur the 

 remains of a genius they call Orohippus, corresponding to the 

 Hyracotherium of the Old World, having four toes on the front 

 legs and three behind ; and a little higher in the beds the Mesohippus 

 appears with three toes in front and only a rudimentary fourth. 

 This leads us on to Miohippus having the fourth digit in a still 

 more rudimentary condition ; and thence to the Hipparion, and 

 thus the chain is completed. 



About sixty were present and the usual vote of thanks was 

 accorded. 



