216 STATHER : NOTES ON THE DRIFTS OF THE HUMBER GAP. 
During the summer of 1896, 373 boulders of Sin. and upwards 
in diameter were noted in the cliff and on tlie adjacent beacli, the 
rough classification of which yields the following results : — 
Per cent. 
69 Carboniferous Limestones ... ... ... 18 5 
104 Sandstones, Grits, Conglomerates, &c., probably 
nearly all from Carboniferous or other Palaeozoic 
Rocks ... ... ... ... ... 27-9 
49 Sandstones, &c., probably nearly all of Mesozoic 
Age ... .. ... ... ... 131 
21 Lias ... .. ... ... ... 5'9 
10 Chalk (including four black flints) ... ... 2*6 
88 Basaltic and other Eruptive Rocks ... ... 23*5 
32 Granites, Schists, Gneiss, etc. ... ... 8*5 
373 100 0 
A great resemblance is at once perceived between the above lists of 
boulders and similar records from the boulder clays of the Holderness 
coast, especially those taken from the basement series of Bridlington 
and Dimlington." And considering that none of the boulders from 
the Red Cliff section (as far as I am aware), have been referred with 
certainty or even probability to sources west of the Wolds, but on 
tlie other hand almost all the specimens met with can be matched 
from the drifts of the coast sections, it can scarcely be doubted that 
the Ferriby and Holderness boulder clays belong to the same series, 
and have had a common origin. 
Considering the proximity and relative position of the Wolds to 
the Ferriby glacial sections, the low percentage of local Chalk amongst 
the boulders is quite remarkable, and indicates that the material of 
which the clays are composed is almost entirely of distant origin. 
It will be noticed that Belemnitella lanceolata from the Chalk found 
in the clays, is not known as a Yorkshire Chalk fossil, and that the 
flints are different from those in the Yorkshire Chalk. On the other 
*Lamplugh, Drifts of Flambro" Head. — Quart. Journ. (ieol. Soc. , vol. xlvii. 
Glacial Sections near Bridlington, pt. iv., Proc. Yorksh. Geol. 
and Polyt. Soc, vol. ix. 
British Association Erratic Block Committees Reports, 1895 and 1896. 
Transactions Hull Geological Society, vols. i. and ii. 
