492 A. B. Wynne — Striated Pebble from the Salt Range. 



merits which have fallen from the rock while the cave was exposed 

 to changes in the amount of moisture and temperature. The inter- 

 stices get filled with inwashed clay. Sometimes the mouth is 

 blocked by a perfect barricade of large blocks which have fallen 

 from the face of the rock where most exposed. This was very con- 

 spicuous at Plas Heaton. At Ffynon Beuno, however, the fragments 

 at the upper entrance were generally small. It was among these 

 that the flake was found. 



I do not, however, attach so much importance as some do to the 

 questions connected with the flake. It would be difficult enough to 

 prove that the group of animals found in the Ffynon Beuno caves 

 were Pre-Glacial, for they are the animals commonly found associated 

 with Palaeolithic Man, and do not even include what we are accus- 

 tomed to consider the oldest forms amongst them. 



To sum up. Firstly, the deposits of the Ffynon Beuno caves 

 cannot have been formed before the submergence, because rocks first 

 brought into the district during the submergence are found among 

 them. They cannot have been formed during the submergence, 

 because the bone deposits at the mouth would have been washed 

 away, and the deposits inside would have shown some evidence of 

 sea-sorting. So they must belong to an age later than the sub- 

 mergence, and a fortiori later than the Glacial age. Secondly, the 

 blocking of the upper entrance seems to have taken place gradually; 

 and while it was going on, drift material was washed into the cave, 

 and various objects got into the crevices of the broken limestone 

 talus ; but the lower end of the cave, next the precipice, remained 

 open. Thirdly, the palasontological evidence is against the Pre- 

 Glacial age of the deposit, as the bones belong to the newer group of 

 animals found elsewhere in undoubtedly Post-Glacial river deposits. 



III. — On a Facetted and Striated Pebble prom the Olive 

 Gkoup Conglomerate or Cliel Hill in the Salt Kange op 

 the Punjab, India. 1 



By A. B. Wynne, F.G.S. 



AMONGST others found by Dr. H. K. Warth, the particular 

 pebble referred to was picked up by its discoverer on the 10th 

 of June, 1886, in about lat. 32° 48' N. and long. 73° 15' E. Its 

 size is 31 inches by 2\ by 2 inches ; and its weight is 101 oz> The 

 material is felsitic rock, the colour reddish-brown, and its density 

 = 2-608 (that of albite being 2-59—2-64). 



The age of the Olive Group, from which the pebble came, is pre- 

 Tertiary and probably later Secondary, but has even been assumed as 

 Carboniferous, upon what the author believed to be inconclusive 

 evidence. 2 



The pebble itself is smoothed, polished, and striated upon twelve 

 different surfaces. Of these about six are perfectly flat, others less 



1 Paper read before the British Association, Birmingham. 



2 See Geol. Mag. Decade III. Vol. III. p. 232, 1886. The specimen itself is in 

 the Museum of the Department of Science and Art in Dublin, and the enlarged 

 photograph referred to was presented to the Geological Society, London. 



