James Oeikie — On Changes of Climate. 



109 



horizon as the shelly Clays of Scotland. It is quite certain, at all 

 events, that these latter, apart altogether from paleeontological con- 

 siderations, cannot possibly represent any part of the middle or 

 lower glacial series of East Anglia. 



The latest glacial deposits in England are the valley moraines of 

 Wales and the north. When I say the latest, I do not mean to assert 

 that any hard and fast line can be drawn between them and the 

 esker- drift and erratics. Glaciers no doubt existed in our upland 

 valleys during the dispersion of erratics, but they lingered on after 

 the re-elevation of the land. 



Throwing the general results now obtained into a tabular form, 

 the succession, it will be seen, closely agrees with that of the 

 Scottish drifts. I begin with the lower beds. 



Glacial Deposits of North-west 

 OF England. 



1. Till; Lower and Upper Boulder-clay 



with Middle Sands.i 



2. (Not recognized).- 



3. Esker Drift. 



4. Erratics. 



5. Valley Moraines. 



Glacial Deposits 'of East Anglia.^ 



1. Lower, Middle, and Upper Glacial 



Groups. 



2. Wanting. 



3. Marine Gravels. 



4. Hessle Gravel, Nar beds, Hessle Clay. 



5. Wanting. 



In Ireland, a tough stony clay, similar in all respects to the 

 Scottish Till, has long been recognized, and underneath it, in some 

 places, a " pre-glacial drift" is found, which occasionally contains 

 the remains of trees, etc.* 



A few years ago, Professor Harkness showed^ that in County 

 Wexford shelly sands occur below an "upper Boulder-clay," and 

 these sands he took to be the same as certain other sands in the east 

 of Ireland, which are seen to rest upon a " lower Boulder-clay." 

 Great caution, however, is requisite in correlating glacial beds. It 

 would appear that in the esker-drift of Ireland, which, like the Scot- 

 tish kame-drift, is of later date than all the Till and Boulder-clay 

 deposits, there occurs a similar assemblage of marine shells as that 

 which characterizes the " Manure Gravels, " with their cap of 

 Boulder- clay. ^ In the absence of such an overlying Boulder-clay, 



^ It may be as well to remark that I offer no opinion as to the contemporaneity 

 or non-contemporaneity of the Lancashire Middle Sands, and the Middle Glacial 

 group of Mr. Wood. The balance of evidence appears to be against the synchronism 

 of these deposits, but the question will, no doubt, be settled by-aud-by — the zeal 

 with which the deposits are being overhauled by Mr. Wood and his confreres in East 

 Anglia, and by Mr. De Eance, Mr. Mackintosh, and others in the North of England, 

 leaves one in no doubt about this. All I hold is that the beds grouped under No. 1 

 were laid down during the same great epoch, and are thus the equivalents of the 

 Scottish Till and interglacial beds. 



^2 It is possible, however, that some portion of the deposits in group 5 may belong 

 to this period. 



3 I follow, of course, the sequence given by Mr. Wood. See Geol. Mag., Vol. 

 VII., p. 18. 



* See Notes on some of the Drift in Ireland by G. H. Kinahan. Dublin Quart. 

 Journal of Science, vol. vi., p. 249. I am indebted to Mr. Kinahan for some MS. 

 notes on the Irish drift. ^ Geol. Mag., Vol. VI., p. 542. 



6 See Mr. Kinahan's paper, loc. cit. Possibly, however, some of the deposits 

 referred to by Mr. Kinahan may belong to the "Middle Sand series." 



