NEW SCIENCE OF PALEONTOLOGY 



similar way, various diverse mammalian forms, as the 

 tapir, the rhinoceros, and the horse, are linked together 

 by fossil progenitors. And, most important of all, 

 Professor Marsh has discovered a series of mammalian 

 remains, occurring in successive geological epochs, 

 which are held to represent beyond cavil the actual line 

 of descent of the modern horse; tracing the lineage of 

 our one-toed species back through two and three toed 

 forms, to an ancestor in the eocene or early tertiary 

 that had four functional toes and the rudiment of a 

 fifth. This discovery is too interesting and too im- 

 portant not to be detailed at length in the words of the 

 discoverer. 



Marsh Describes the Fossil Horse 



"It is a well-known fact," says Professor Marsh, 

 "that the Spanish discoverers of America discovered 

 no horses on this continent, and that the modern horse 

 (Equus caballus, Linn.) was subsequently introduced 

 from the Old World. It is, however, not so generally 

 known that these animals had formerly been abun- 

 dant here, and that long before, in tertiary time, near 

 relatives of the horse, and probably his ancestors, ex- 

 isted in the far West in countless numbers and in a 

 marvellous variety of forms. The remains of equine 

 mammals, now known from the tertiary and quaternary 

 deposits of this country, already represent more than 

 double the number of genera and species hitherto found 

 in the strata of the eastern hemisphere, and hence af- 

 ford most important aid in tracing out the genealogy 

 of the horses still existing. 



"The animals of this group which lived in America 



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