LAMPLUGH : CHALK OF FLAMBRO' HEAD. 
245 
pebbles worked into it, and sometimes passes into a kind of 
Boulder Clay. 
It is most accessible, and best developed, just where a cave 
which opens into Selwicks Bay, shows, through the fall of its 
roof, a wide, gaping chasm to the land, not far from the Fog-gun 
house. It has a thickness here of not less than 10 feet. 
The chalk below it possesses evidence of ice pressure in the 
form of a few slight crumplings which die away gradually down- 
wards. 
Similar patches of travelled beds have been noticed in the 
Boulder Clay near Filey ; which are probably, however, not so 
far from home, being derived from the Middle Kimmeridge series. 
These patches seem to have been looked upon by Mr. Judd in his 
well-known paper on the Speeton Clays* as being in place ; but 
this is not the case with any I have yet seen. Even in an ex- 
posure which I noticed on the shore, near Filey, the Kimmeridge 
Clay was surrounded by Boulder Clay. 
Speeton fossils are not very rare in the 1 Basement' Clay either 
at Bridlington or Dimlington. 
These, and kindred facts, should be of value in tracing the 
probable direction of the ice-flow. 
I may mention, too, that the ' Basement ' Clay of Mr. S. V. 
Wood, appears to have an out-lier in the cliff at Selwicks just 
above the slip that covers the fault ; but as the whole section 
here is much obscured, it is difficult to make out its relations. 
Enough that it possesses the characteristic peculiarities of that 
clay, and contains, as usual, an abundance of broken shells of 
northern species. 
*Quart. Geol. Journal, vol xxix page 219. 
I 
