II PROGRESS OF PALAEONTOLOGY 33 



physiological reasonings. Every one practically 

 acquainted with palaeontology is aware that it is 

 not every tooth, nor every bone, which enables us 

 to form a judgment of the character of the animal 

 to which it belonged ; and that it is possible to 

 possess many teeth, and even a large portion of 

 the skeleton of an extinct animal, and yet be 

 unable to reconstruct its skull or its limbs. It 

 is only when the tooth or bone presents peculi- 

 arities, which we know by previous experience to 

 be characteristic of a certain group, that we can 

 safely predict that the fossil belonged to an 

 animal of the same group. Any one who finds a 

 cow's grinder may be perfectly sure that it be- 

 longed to an animal which had two complete toes 

 on each foot and ruminated ; any one who finds a 

 horse's grinder may be as sure that it had one 

 complete toe on each foot and did not ruminate ; 

 but if ruminants and horses were extinct animals 

 of which nothing but the grinders had ever been 

 discovered, no amount of physiological reasoning 

 could have enabled us to reconstruct either 

 animal, still less to have divined the wide differ- 

 ences between the two. Cuvier, in the " Discours 

 sur les Revolutions de la Surface du Globe," 

 strangely credits himself, and has ever since been 

 credited by others, with the invention of a new 

 method of palseontological research. But if you 

 will turn to the " Recherches sur les Ossemens 

 Fossiles " and watch Cuvier, not speculating, but 

 VOL, IV i) 



