522 
THE GEOLOGIST. 
flood — could have been sncli as we observe so constantly in these 
bone-breccias. 
The titter insufficiency of this way of solving the difficulties which 
these collections present may be seen in the account given by M. 
Alfred Tontan of two bone-caverns in the Montague du Ker, at 
Massat, in the Department of Ariege, as extracted from the November 
number (68) of the Quarterly Journal of the Geological Society of 
London, page 4G8. 
After noting that there are many of these hollows or grottos in the 
mountain, he says : " Amongst these caves, two are remarkable on 
account of their extent. One of them, situated near the summit of 
the mount, at an elevation of about a hundred metres (three hundred 
and thii'ty feet) above the bed of the valley, is approached by a 
spacious vestibule, or outer chamber, with two large and lofty circu- 
lar entrances, one of which faces the north, the other north-north- 
west. The soil of the outer chamber, which, like the rest, was devoid 
of all stalagmitic concretions, was smooth and horizontal, rising 
above the sill of the entrance. With the exception of a small por- 
tion near the north-north-west entrance, where a few fragments of 
pottery were found, mixed with cinders and coal, it presented the 
appearance of an abandoned river-bed. A sandy loam, sprinkled with 
gravel or small rolled pebbles, occupied the centre ; whilst at the 
edges, against the wall of rock, larger but similarly rolled pebbles 
appeared to have been thrown up by the eddying or movement of 
the water. These deposits continued in the same way for a distance 
of a hundred metres along the principal gallery, only diminishing in 
thickness as they extended farther inwards, and entirely ceasing at 
the further end. 
" This arrangement, combined with the presence at such a consider- 
able elevation of rolled pebbles, most of which were different from 
the rocks of which the mountain consists, appeared to the author as 
solely attributable to those diluvial cataclysms which geology points 
to as having occurred at several periods anterior to historical tradi- 
tion. In order to understand these facts, he determined to study the 
nature of the deposits ; for which purpose he caused a deep trench 
to be dug in the soil near the northern opening, and extended it to 
the lateral wa]]s.. The result of this first attempt was the discovery 
