162 Proceed in<jis of the Royal Irkh Academy. 



This description, taken from the deposits of tlie Tay basin, applies 

 equally to those of the Porth, except that here tlie peat has not been 

 actually seen. Canoes and "rude imjdements and weapons" have 

 been found in the Carse clays down to a considerable depth, but 

 rarely. Subsequent to the deposition of the Carses, the sea retired 

 from about 50 feet above present level to 25 feet above present level,, 

 where a pause resulted in the formation of well-marked beaches, with 

 which are associated bronze implements ; the fauna shows a climate 

 not colder than the present. The final elevation took place "long 

 after the knowledge of metals had been introduced." 



Tlie author's summary of the succession of events in the valleys of 

 the Tay, Forth, and South Esk, may be digested as follows : — 



(1) . Long after the "retreat of the Glacial sea," the land stood 



higher than at present, and arboreal vegetation extended, 

 widely, in a climate not less genial than the present. 



(2) . Submergence to a depth of 25 to 40 feet below present level. 



Accumulation of marine silts with Scrohictdaria piperata. 



(3) . Accumulation of thick beds of silt. Water generally too fresh. 



in the estuaries for marine molluscs. 



(4) . Elevation until the land stood higher than at present. 



(5) . Depression, bringing about present conditions. 



The extremely close correspondence of this series of events to that 

 we have described in tlie north of Ireland, and also to the Mersey 

 series (p. 158, supra), will be at once noticed. The only important 

 difference lies in the correlation of the fluctuations with the periods 

 of early human history. While making the 50-foot submergence, 

 during which the Carses were formed, Ts'^eolithic, James Geikie dates 

 the 25-foot raised beaches, which resulted from a pause in the emer- 

 gence, as of Bronze Age.-^ But while the evidence shows that these 

 beaches are not newer than that, they may prove to be older, as we 

 believe is the case with the corresponding beach in Ireland. 



In the district of East Fife, while admitting the succession 



(1) . 25-foot raised beach, 



(2) . Peat, 



(3) . Glacial beds, 



1 Loo. clt., pp. 402-3, 428-9. 



