BRITISH POSTGLACIAL & RECENT DEPOSITS. 455 



find tracts of low-level alluvial land bordering the rivers, all of 

 which belong to postglacial and recent times, as is proved by the 

 fact that they have often yielded remains of the true postglacial 

 fauna along with relics of Neolithic and later ages. But what 

 is chiefly noteworthy about those alluvia is this — that in Lin- 

 colnshire and neighbouring districts they everywhere overlie 

 unconformably the more ancient accumulations of gravel, sand, 

 and loam, in which occur the relics of Palaeolithic man and 

 the remains of Pleistocene fauna. A good example of this has 

 already been pointed out as having been ascertained by Mr. 

 Skertchly in the Fenland. No one, indeed, can traverse the 

 counties of Norfolk and Cambridge without observing that while 

 deposits of Palaeolithic age occur frequently on hill-slopes, and 

 even sometimes extend across watersheds, all the modern alluvia 

 are confined entirely to the bottoms of the valleys. In such 

 valleys as the Thames, the latter form in like manner the 

 low-lying plains through which ^the rivers flow, and invariably 

 overlie the true Pleistocene deposits. 



As in Scotland, so in England, evidence is not wanting to 

 show that in early postglacial times the rivers must have flowed 

 in larger volume than at present. In the northern districts, and 

 in Wales especially, the river-gravels of the upper valleys are 

 often comparable with the similar accumulations in the hopes and 

 dales and glens of the Scottish Uplands and Highlands. They 

 tell of streams that more frequently than now assumed a tor- 

 rential character, and I can hardly doubt that it will eventually 

 be found that some of the small moraines in the higher valleys 

 of the northern Lake District and of Wales really belong to 

 Postglacial and Neolithic times. 



Of lacustrine alluvia and peat-bogs there is little more to 

 be said. They resemble in all essential features the similar 

 accumulations in Scotland. In many of the ancient silted-up 

 lakes considerable beds of marl and plentiful remains of the 

 postglacial fauna have been met with, while the peat-mosses 

 have yielded abundant relics of a bygone Age of Forests. From 

 the facts revealed by the submarine forests, which occur upon at 



