PALEONTOLOGY. 273 



master whom I shall always consult in the numerous cases where pru- 

 dence requires me to hesitate. 



If the existence of hearth-stones at somewhat numerous points, 

 but most frequently at the bottom of valleys, as, for instance, on 

 the brink of water courses, and the revelation of a civilization which 

 it would be erroneous at the present day to term rudimentary, 

 should be urged as objections to the relative antiquity of these first 

 inhabitants of the globe, I will reply that wrought flints, split by 

 fire, are met with in the gravels of the table-lands, but the objects 

 which accompanied them have without doubt been dispersed, swept 

 away by the waters. The siliceous matter, from the double advan- 

 tage of its specific gravity and of its indestructability, has alone been 

 strong enough to resist the great currents, while bony and gelatinous 

 substances have disappeared, as I before indicated, under the de- 

 structive influence of atmospheric agents. But, on the other hand, 

 it is necessary to examine the fauna of these hearth-stones : it is 

 identical with those of the bone-bearing conglomerates which sur- 

 round and cover them ; the remains of the reindeer, the urus, the 

 ox and the horse, are found associated with numerous flint-stones of 

 a workmanship of suflS.cient finish at a certain number of points to 

 be compared to instruments of the same nature attributed to the 

 Celtic epoch. It is especially at Combe-de-EoUand, near Angouleme, 

 and at Bourdeilles (in the grotto of the Ass and Devil's Eurnace) 

 that the finest types are met with. In the parishes of Tayac and 

 Tursac the instruments are less perfect, but, in return, bones adapted 

 for use abound.* The hearth-stone of Eoccoutteux at Bourdeilles ; 

 the grottoes of La Chaise and of Montgaudier, near Montbron, 

 have furnished analogous specimens, but in smaller number. At 

 Bourdeilles wrought flints are met with in the valley, but they are 

 again found at all heights, and in the defiles.f They were undoubt- 

 edly carried along by the impetuosity of the same currents as have 

 worn away the rocks not only in the sloping parts of the valley of 

 erosion, but up to the summit of the table lands. If we were 

 tempted to attribute to some convulsion the deposition of the Ass* 

 Cave at Bourdeilles, I would observe that the calcareous sediments 

 are found even in the upper part of this cave, and that they contain 



* utensils, arms, or designs, 252 ; reindeer horns, notched or sawed, 280 ; itag horns in the 

 8&me state, 9. 



t Th» exploration of this defile has led to the discovery of a human molar, which I iuc* 

 «eeded in taking out with my own hands. 



