90 LECTURES 



lesson it teaches those who may be more or less unin- 

 formed in such matters and everyone here present being 

 on the right side of the line, may smile at the class to 

 whom I refer is invaluable. It will well exemplify the 

 certitude of the predictions of biologists in such premises, 

 equipped as they are with their present-day acquired 

 morphological facts, as it likewise proclaims that it is 

 not even necessary to have in our possession the entire 

 skeleton of the fossil remains of the animal discovered to 

 safely predict as to its position in the natural system. A 

 split slab of stone, of considerable geological age, from 

 the quarries of Montmartre is presented to the distin- 

 guished French savant Cuvier. Its two halves contain 

 the greater part of the skeleton of a small mammal, but 

 only a few of the teeth of the lower jaw happen to be 

 exposed, and these Cuvier carefully examines. The 

 exposed material you will at once appreciate is but frag- 

 mentary, yet that sagacious French biologist made no 

 hesitation in pronouncing the animal an opossum, guided 

 as he was by the evidence in sight, and duly assigned the 

 fossil to that genus. Opossums are unlike most of the 

 mammalia, inasmuch as they possess two small bones, 

 articulated mesially to the fore part of the pelvis, which 

 have been called the "marsupial bones," but the function 

 of which has not been definitely determined. Now, al- 

 though the animal Cuvier had in hand had been dead and 

 fossilized and encased in rock for untold ages, he prophe- 

 sied that when they came to clear away the matrix which 

 contained it there would be discovered, in front of the 

 pelvis, the two usual bones that characterize that part of 

 the skeleton in the opossums, and this prediction he made 

 from an examination, you will remember, of only a few 

 of the teeth. Other naturalists were invited to witness 

 tne disinterment, so confident was Cuvier of his predic- 

 tion, and, be it said to the credit of biological science, he 

 was most eminently correct in his ideas, for the marsu- 

 pial bones of the fossil were duly exposed in situ. Now 

 the application of such a philosophy as this not only 

 holds true of mammals, but it holds true of all animals 

 and plants whatsoever, that have ever existed since the 

 beginning of the world. Not only this, but with the in- 

 crease and the better knowledge of such material, our 

 prophecies can be made with an ever increasing certainty 

 of their correctness, so that, in time, without ever having 

 seen certain fossil animals at all, it will become possible 

 for the skilled palaeontologist to very closely designate 

 the various kinds that must have of necessity existed; 



