Vol. 62.] AN UNCONFORMITY IN THE COAL-MEASURES.- 



539 



has quite recently been exposed (November 15th, 1905), as shown 

 in the accompanying sketch-plan (see ng. 11, p. 540). 



At the northern end (M) of this bay are several parallel stony 

 ridges similar to those described farther on (p. 546). From this point 

 onwards to IS", the cliff-section presents a number of complications, 

 which, while they emphasize the evidence in favour of a thrusting- 

 movement from south to north, at the same time render it difficult to 

 follow clearly the line of unconformity. The accompanying diagram 



Fig. 10. — PhotograpJi showing the ridge on the foreshore at J. 



[The ridge is marked by two white crosses, and is seen to end abruptly 

 seaward, that is, to the right of the photograph.] 



(PI. XLII) will show the main features of the case better than 

 a detailed description. The difficulty is partly due to the fact that 

 from M northward, the lower course of the Table-Hocks Sandstone 

 loses much of its continuously-massive character, being partly 

 replaced by shale in which tongues of sandstone from the higher 

 portions of the deposit are here and there intercalated, as well 

 as isolated lenticular patches of sandstone. Much of this lower 

 course is also concretionary. Pebbles are fairly plentiful, but 

 appear as a rule to be limited to the bottom of these irregular 



