LECTURE IX. 251 



formed. The floor of the cave still shows a small pond, on the 

 right side of which was formerly an opening. There the de- 

 posits of pebbles and mud rose to the roof, forming a large cone, 

 which obstructed the fissure through which the waters entered. 



The cave lies far above the influence of the present state of 

 the waters, on the declivity of a steep mountain, in which, 

 among others, open also the remarkable caves of Sabard and 

 Niaux, which are on the same level, show the same deposits, 

 and were probably connected at an earlier period. In the 

 valley of Vicdessos, above the village Niaux, are seen well- 

 characterised diluvial formations, composed of the same ele- 

 ments as those in the caves. 



The deposits in the cave consist of regular layers of rolled 

 stones, sand, clay, and mud, which are very distinctly seen in 

 the background of the caverns where the stalactite roof is 

 wanting. 



Large rolled stones, sometimes a meter in diameter and 

 rather disconnected, form the lowest stratum (6, fig. 84), some- 

 times resting immediately upon the jura lime, sometimes upon 

 the stalagmite. Where this layer is exposed, it resembles the 

 bed of a forest brook, upon which walking is rendered difiicult 

 (5, fig. 84). 



These two layers of rolled stones contain all specimens of the 

 rocks of the Pyrenees ; they are identical with the rolled 

 stones of the diluvium of the adjoining valleys, where are also 

 found rolled fragments of stalactite. 



Above these rolled stones lies a stratum of grey plastic clay, 

 (4,) which is preserved in but few spots, having been washed 

 off in the rest. 



A fine ferruginous and calcareous sand, a real loam (3), 

 forms the uppermost layer of the diluvial deposit ; it fills up 

 the parietal grooves, and even the grottoes, to a height of ten 

 meters above the level of the cave. In some spots, where 

 there was a rotary motion, it forms considerable elevations. 

 In this loam, and sometimes in its stalagmite incrustation, lie 

 human bones intermixed with those of carnivorous and herbi- 

 vorous animals, namely, of the brown bear, urus, reindeer, 

 stag, horse, and some undetermined species of a small kind of 



