40G LAMPLUGH : LARGER BOULDERS OF PLAMBOROUGII HEAD. 
protrusion of the promontory, the peculiarity is readily explicable. 
However as I have a paper in preparation wherein the drifts of the 
headland are to be fully described, it will perhaps be more convenient 
to defer for the present further discussion of the theoretical bearing 
of the facts now recorded. 
With regard to the question as to how far these larger boulders 
are reliable as guides to the origin and proportion of the stones in 
the drift, 1 gave in a former paper* my reasons for preferring them 
to the smaller pebbles as evidence of ice-movement. I have however 
commenced an investigation, complementary to the present work, of 
the smaller pebbles only, and hope at some future time to make 
known the result. So far as 1 have gone the proportions of the 
smaller pebbles agTee more closely with those of the larger boulders 
than I had expected, the chief difference being that hard crystalline 
rocks, especially vein-quartz, are more abundant among the pebbles. 
Appendix to Part IV. 
SOME or THE MORE IMPORTANT BOULDERS BETWEEN SOUTH SEA LANDING 
AND HIGH STACKS, FLAMBOROUGH. 
The prefixed number indicates the ordinal position of the boulder 
In the original full list. All dimensions are in inches. The sign + 
indicates that it has been impossible to obtain the full measurement. 
The asterisk * denotes that there is a petrological desc7'iption of the 
boulder in Mr. Barkers notes. 
No. 
*1. Position : On the beach near Old Falls. Descrijytion : Fine- 
grained Basalt. Size and shape : Oblong, flat sides. 54 x 36 
X 30 inches. 
*15. Opposite Limekiln. Coarse greenish Dolerite. Oval, rounded. 
14 X 8 X 4 inches. 
*21. Near same place. Porphyritic Dolerite or " Augite-porphyrite."" 
Size and shape similar to No, 15. 
rroc. Yorksh. Geol. and Polyt. Soc, vol. xi., pi. iv.. p. 233. 
* Theee terms are taken from Mr. Barker's notes. 
