104 FOSSIL MAMMALIA. 



occupied by the plaster-quarries, more than twenty leagues 

 from east to west, that scarcely any bones but those belonging 

 to a single family should be found. The remains of the small 

 number of species different from this family discovered there, 

 are rare in the extreme. It is not to be doubted that the 

 number of bones of each species found in the fossil state, bears 

 a relative proportion to the number of animals which once 

 existed on the soil, for it is impossible to imagine any destruc- 

 tive agency, that could have overwhelmed or incrusted in the 

 gypsum, the bones of any one species in preference to those of 

 another. 



In the present state of the globe we find animals of almost 

 all families inhabiting the countries which compose all our large 

 continents, according to the degree of latitude, and the nature 

 of the soil. But this is not at all the case with the larger 

 islands of the earth. The actual state of New Holland, in par- 

 ticular, may serve to illustrate the probable state of that part 

 of France which was once inhabited by these ancient pachyder- 

 mata. Five-sixths of the quadrupeds of that island belong to 

 one and the same family, namely, the marsupialia. There are 

 six genera of these approximating very closely to each other, 

 and having nothing analogous in the animal world, except the 

 didelphes of the warmer regions of America. To these we 

 may add the ornithorhyncus and echidna, which exhibit close 

 relations to the pouched animals. The number of species in 

 these genera are more than forty, and there are but eight or 

 ten species of other mammalia to oppose to them in the whole 

 country. 



Here, then, we find in a considerable, but isolated, region, 

 a proportion in the number of its quadrupeds very similar to 

 what appears to have obtained formerly in the country inha- 

 bited by those ancient animals. Among a dozen or fifteen 

 pachydermata, we find but two or three carnivora. This 

 resemblance has led the Baron to conjecture, that, at the era 

 in which those animals lived, the country which they occupied 



