96 PERIOD IV. 



the valley of the Seine a large population of animals, all 

 now extinct, had formerly flourished. None of these 

 discoveries impressed his contemporaries more than the 

 celebrated case of the fossil opossum. The bones were 

 imbedded in a slab of gypsum, and were at first imper- 

 fectly exposed. The lower jaw, however, exhibited 

 a peculiarity of marsupial or pouched animals, for its 

 angle had an inwardly projecting shelf, not found in 

 other quadrupeds. The opossums, like all marsupial 

 animals, bear on the front of the pelvis two long bones,, 

 which support the pouch. These were as yet concealed, 

 and Cuvier delayed clearing them until he had sum- 

 moned friends, some of whom may have been sceptical 

 about the possibility of reasoning with certainty from 

 anatomical data. Warning them what to expect, he 

 removed with a sharp tool the film of stone, and 

 revealed the long and slender marsupial bones. 1 The 

 ancient existence of marsupials in France was then a 

 striking and almost incredible fact ; increase of know- 

 ledge has not lessened its interest, though it has abated 

 some of the wonder. 



The fossil ungulates (hoofed quadrupeds) of the Paris 

 basin taxed Cuvier's patience and skill to the utmost. 

 In the tiresome work of piecing together a multitude 

 of imperfect skeletons he set an example to all future 

 palaeontologists. That he drew general conclusions 

 which we are unable to accept, and failed to draw con- 

 clusions which seem obvious to us, will surprise nobody 

 whose reading has taught him how unprepared were 

 the biologists of that age to handle great questions 

 concerning the origin and extinction of races. Cuvier 

 recognised among the fossils of the Paris quarries the 



1 This anecdote has also been related in a rather different 

 form. 



