LOWER PALEOZOIC ROCKS OF HAVERFORDWEST. 491 



possibly be interpreted. The succession of the rocks in this district 

 had never been unravelled till the Authors undertook the task. 



Prof. HrGHEs remarked on the absence of the evidence of the 

 occurrence of the Harlech Grits except the basement-bed, of the 

 Menevian, the Tremadocs, part of the Arenigs, and other forma- 

 tions. He thought the Hirnant limestone really consists of two 

 members which are separated by a great break, and the lower of 

 these only is represented by a limestone in the area described. He 

 thought it probable that the equivalents of the Upper Conglo- 

 merates might be found in the Malvern district, and that they form 

 the base of the Silurian. 



Mr. Mark thought that the beds in Trefgarn-Bridge Quarry exhibit 

 signs of faulting, which may account for the apparent absence of 

 some of the strata. He thought that a great confusion had arisen as 

 to the position of the conglomerates at the base of the Silurian. 



