DUPONT CAVEEls^S OF THE LESSE. 27 



sandy argillaceous beds occur, as well in the caverns as in the sub- 

 aerial formation of the province of Namur, between the great deposit 

 of rolled pebbles on the one hand and the argillaceous deposit with 

 blocks on the other. 



But, as in the valley the deposit of rolled pebbles is characterized 

 by the abundant remains of Mephas'primiffenius, these beds may be 

 named the beds with Eleplias primigenius (couches k Elep>has primi- 

 genius). On the other side, the deposit of yellow clay with blocks, 

 which is the equivalent of the diluvium rouge of the Paris basin, 

 contains the fauna of the Eeindeer properly so called, the charac- 

 teristic of which is the absence of extinct species, and the presence of 

 a series of animals which are at present banished to colder climates. 

 These facts confirm, in the author's opinion, his division of the Qua- 

 ternary formation into three stages : — 



Etage superieur a Cervus tarandus. 

 Etage moyen a TJrsiis speloius. 

 Etage inferieur a Eleplias primigenius. 

 Trou de la Naidette. — This cavern is on the left bank of the Lcsse, 

 about 60 yards up the river from the '' trou des blaireaux." It is 

 27 feet above the river, is more than 40 yards long, and has a 

 breadth in the middle of 12 yards. At the entrance to the cavern 

 was a thick deposit of yellow clay with blocks, containing bones of 

 the Horse, Eeindeer, dtc, which thinned out so rapidly that at 

 4 yards from the entrance there was not more than a trace of it. 

 There a falling in of part of the roof had completely hidden the 

 Quaternary deposits. Towards the extremity of the cavern, some 

 well-stratified sandy argillaceous beds were laid bare, not overlain by 

 the clay with blocks. A sinking made here presented the following 

 section : — After passing through 9 feet of sandy clay and j-ellow sand, 

 followed by 14 inches of yellow clay with fallen stones («), cones of 

 stalagmite, and bones of ruminants, 4L feet of alternating beds of 

 clay and stalagmite were reached. This was followed by sandy clay 

 and sand, about 4 feet in thickness, which contained at its base the 

 head of a Wolf and some vertebrae. In this bed (h) nearly aU the 

 bones mentioned hereafter were found. Below this, beds of sandy 

 clay and sand were reached, followed by a gravelly sand, until traces 

 of red clay were discovered. 



The bone-bearing beds occurred at two levels. The upper one (a) 

 contained some bones (especially single rami of the jaw) of an unde- 

 termined Euminant. 



The lower level {h) furnished, however, the most important series 

 yet obtained from the caverns on the banks of the Lesse. The bones 

 were not numerous, but were in an admirable state of preservation. 

 The principal species were the "VYolf, Ursus arctos, Fox, Badger, 

 Bat, Marmot, "Water-rat, Elejylias primigenius, Rhinoceros, Horse, 

 Reindeer, Wild Boar, Chamois, Common Stag, Sheep, and a fish. 

 But the great importance of the discovery consisted in the presence 

 in the midst of the bones of a human jaw and cubitus, and of a bone 

 with a hole artificially produced. The association of the human 

 remains with the rest of the bones was beyond a doubt. 



