CUVIER. 



165 



The Fossil Opossum of Montmartre (Didelphys gypsorum), showing the 

 ' marsupial bones ' attached to the brim of the pelvis (m\ 



It is needless to add that this demonstration of the value 

 of the law of the correlation of organs in palseontological 

 researches excited the greatest admiration, and was 

 regarded as absolutely conclusive. In one important 

 point it was indeed conclusive ; since no known animal 

 outside of the order of the Marsupials is known to have 

 both an inflected angle to the lower jaw, and also mar- 

 supial bones on the brim of the pelvis. 



The conclusiveness arose, however, from the fact that 

 Cuvier found both these structures together ; and we now 

 know that the presence of the one would not necessarily 

 prove the presence of the other. Cuvier knew this himself 

 so far as the presence of ' marsupial bones ' is concerned, 

 because he knew that these bones occur in the duck-mole 



