926 PROFESSOR J. PRESTWICH ON THE EVIDENCES OF A SUBMERGENCE 
intimately connected with No. 2, into which it passes by insensible degrees. It 
generally accompanies bed No. 2, hut it also extends beyond it and attains to much 
greater heights, often covering the country like a mantle. This agrees exactly 
with some of the main physical characters of the rubble-drift in England. The 
organic remains are too variable a quantity to affect this conclusion. None, in fact, 
have been recorded in the rubble bed in this district, except when in connection with 
the caves; but Helix concinna, H. hisjDula, Pupa marginata, and Succinea oblonga, 
have been found in the loam (l). M. Dupont further describes how intimately much 
of the Loess of Belgium is connected with these beds. The observations of M. Briart 
{ante, g. 923) confirm this view, which is one I shall have occasion to develop more 
fully presently. 
M. Dupont also shows that in the neighbourhood of Dinant, the “ Argile d 
hlocaux ” is frequently present, and forms a well-defined division between the cave 
beds and the deposits of the Stone Age. One of the most typical of these caves is 
that of the “ Trou du Frontal on the banks of the Lesse, and which I had the 
opportunity of visiting with M. Dupont, not long after its exploration. A copy of 
this section, and of his description of it, is given below (fig. 12). 
M. Dupont divides the cave deposits into two groups, assigning beds 3 and 4 to the 
Mammoth age, and No. 2 to the Beindeer age in consequence of the scarcity in this 
latter of the larger Quaternary Mammalia and the abundance of Beindeer remains. 
But is not this preponderance caused by the circumstance that during the deposition of 
the beds No. 3, the cave was frequently flooded and only occasionally inhabited by 
Carnivorous animals or visited by Man ; whereas, after the deposition of those beds, the 
cave, or rather shelter, being then out of the reach of the floods, was often frequented by 
Paleolithic Man, and became consequently the floor on wdiich were scattered the flint 
tools he used and the remains of the animals on which he fed, such as the Beindeer, 
Wild Boar, Ox, Horse, &c., and the other animals named by M. Dupont ? 
The contents of caves necessarily vary according to their occupants for the time 
being. The spoil of the Hysena will differ from that of the Bear, and those, again, 
from that of Man. For this reason I doubt whether the caves afford a just means of 
classification. Outside the caves the same animals may have inhabited the Avoods and 
plains during the whole of the late Glacial or Post-glacial time, and that seems to me 
the conclusion to be drawn from the other evidence than that of caves. Certainly 
the Beindeer existed throughout that period, though its distribution may haA'e 
varied ; while the contents of the rubble-drift, AAdien not connected with the caA'es, 
show that the Mammoth and other great extinct Mammalia Avere common at the time 
of its formation, and, therefore, at the time of the so-called Beindeer Age. 
Though I should agree wuth M. Dupont in considering the “ Argile a hlocaux ” 
distinct from the cave beds beneath, I look upon the organic remains in that deposit 
* ‘Bull. Acad. Roy. de Belgique,’ 2nd Ser., vol. 20, No. 13, Plate 3; and ‘ L’Homme pendant les 
Ages de la Pierre dans les Environs de Dinant-sur-Meuse,’ 2nd edit., 1872. 
