PLEISTOCENE LOAMY DEPOSITS. 155 



overlaid by loamy deposits {Limon hesbayen), which sweep up to 

 higher levels and extend across the plateaux. These latter con- 

 sist of a lower yellowish, unstratified, fine-grained, calcareous 

 loam or loss, from 6 feet to 30 or 40 feet in thickness, and an 

 upper reddish or brown, unstratified, non-calcareous, and argil- 

 laceous loam, which is often sufficiently plastic to be used for 

 the making of bricks. Above the limits of the ancient valley- 

 gravels these loamy deposits are often underlaid by sandy earth 

 and stones, which correspond to the similar accumulations 

 occupying a like position in the plateaux of the north of France. 

 Occasionally also beds of coarse sand appear on the same 

 horizon, but they are of little extent, and occur for the most part 

 in depressions or hollows. The lower portion of the loss-beds 

 has all the characters of Rhenish loss. It is yellow in colour, 

 unstratified, and more or less calcareous, and it shows the 

 characteristic vertical capillary structure ; it likewise con- 

 tains land- and freshwater-shells of the usual species, such as 

 Helix hispida, Pupa rnuscorum, Clausilia laminata, Bulimus 

 ohscurus, Succinea oblonga, etc. The upper portion, as just stated, 

 differs from the lower in colour and composition. It does not 

 effervesce with acids and is frequently plastic, which is not the 

 case with the lower. The shells it contains are chiefly helices, 

 such as IT. nemoralis, H. hortensis, U. lapicida, and H. rotundata. 

 According to the Belgian geologists this upper clay is distin- 

 guished by the presence of remains of the reindeer, while those 

 of the mammoth occur in the lower or lossic portion. I may 

 note also that Professor Malaise has recorded the discovery of 

 Palaeolithic implements under the loss in the neighbourhood of 

 Spiennes, south-east of Mons. 



M. Dupont, it will be remembered, has described the occur- 

 rence in certain caves in the province of Namur of clay with 

 angular blocks. He likewise mentions the interesting fact that 

 this stony clay is occasionally overlaid by loss, as in the following 

 section, which gives the results obtained from an examination 

 of several caverns : — 1 



1 Bull. Acad, de Belg., 2 e Ser. t. xx. -p. 284. 



