Professor Pictet on Fossil Bones. 239 



mote from all streams of water of any consequence, cannot 

 have been deposited by a special accident, and that they owe 

 their origin to the general cause which deposited the alluvial 

 formation of the basin of the lake of Geneva. 



I think, therefore, that we may consider it as a fact, that 

 the animals whose skeletons are found there, have lived in 

 our valley during the period immediately preceding the de- 

 position of this diluvian formation. 



I shall afterwards shew that all these animals belong to 

 the same species as those which now live in these same 

 countries. From this circumstance, the discovery of these 

 bones may appear of little interest, and it may perhaps seem, 

 at first glance, that little instruction can be derived from the 

 study of them. I shall endeavour, on the contrary, to shew 

 that this fact, apparently unimportant, is, in reality, con- 

 nected with one of the most essential laws of palaeontology, 

 and may influence the solution of the most delicate questions. 

 But I must previously prove this identity of species ; and I 

 have devoted, to this comparison, the time and attention 

 which this essential point seemed to merit, and which will 

 form a foundation for the reflections which shall terminate 

 this memoir. 



[The original memoir here enters into details respecting 

 these various bones, and the list of the species discovered. 

 These gravels contain a Sorex araneusy the mole, martin, pole- 

 cat, weasel, the fox, a rat (probably referable to the Mus leu- 

 cogastor, Pict., and which seems to prove that this species had 

 preceded man in our countries, and had not been imported by 

 means of maritime commerce, like the common black and 

 brown rats), the field mouse, domestic mouse, Schennaus, 

 Arvicola subterraneus, the common campagnol, a pig, an ox, 

 the chamois, a sheep or a goat, a passerine bird, the common 

 toad, the green frog, and green lizard.] 



The comparison of the fossil bones of our gravels with the 

 skeletons of living species, as well as analogous facts, which 

 may be collected even to the present time, prove, in my opin- 

 ion, with complete evidence, that the animals which peopled 

 our valley before the diluvian formations were deposited, are 

 identical with the presently existing species. This conchi- 



