442 MK. D. PIDGEON ON CEETAIN PECULIARITIES OF 



from deeper water than the rock-dwelling Gasteropods forming so 

 large a proportion of the deposit, they were sure to suffer more 

 trituration than the latter from floes on their way from compa- 

 ratively deep water to the " trench." 12. If Troplion truncatus 

 proves anything, it must be that the climate was colder during the 

 accumulation of the deposit than it is to-day. 



All the foregoing remarks, together with the speculation founded 

 upon them, apply solely to the " raised beaches " of Hope's Nose 

 and the Thatcher liock. About the physical peculiarities of other 

 raised beaches the author does not here pretend to speak ; but if it 

 should be admitted that the two raised beaches in question are not 

 " beaches " at all, it is probable that other similar deposits will pro- 

 fitably bear re-investigation. Meanwhile, if the writer's hypothesis 

 should stand the strain of criticism, it would appear probable that 

 the " raised beaches " of Hope's ISJ'ose and the Thatcher Rock are 

 phenomena marking the close of the Glacial Period in England. 



Discussion. 



The President remarked that anything which might throw light 

 on what took place in Glacial times in the non-glaciated regions of 

 Southern England would be welcomed by geologists. 



Mr. Usshee asked if the Author would not expect the stones in 

 the beach to show some traces of glaciation if his explanation were 

 correct. He was glad to hear that the Author considered that colder 

 conditions prevailed during the formation of the beaches, though he 

 himself did not think that the climate was Arctic. He instanced 

 the occurrence, on a pinnacle 30 yards from the main cliff, of a 

 fragment of raised-beach platform which was originally talus from 

 the high ground behind the beach. 



Prof. Hughes was glad to hear that these were not exactly beaches, 

 but subaerial accumulations with shells and pebbles thrown up in 

 storms, as he had supposed from an examination of the Braunton 

 beach, and did not therefore necessitate any considerable changes 

 of level. He, however, saw no necessitj^ for glacial action to account 

 for the phenomena. TrojjJion clatJiratus and Mcmgelia turricida 

 were elsewhere associated with Scandinavian shells, but he con- 

 sidered them to be last survivors from former colder conditions. He 

 did not understand how the materials were thrown over the ice-foot. 

 The materials were comparable with those of modern talus. Iso- 

 lated pebbles were thrown to a great height above sea-level. 



Mr. Clement Eeid maintained that the shells were common British 

 species. The fact that Parjiura was less worn than the bivalves was 

 paralleled on the ledges above modern beaches. He could not agree 

 with Prof. Hughes as to the " raised beaches " of the south of 

 England having been accumulated by the sea at its present level : 

 for in Goodwood Park, 7 miles from the coast, they are found up to 

 a height of 130 feet. The fauna of these is distinctly not Arctic. 



The President had seen these beaches. It never occurred to him 

 at the time that they afforded evidence of glacial conditions, though 



