610 REV. J. P. BLAKE ON THE 



well-exposed rocks overlooking Malldraeth marsli, we find, in about 

 a mile, that slaty rocks of compact and banded aspect, which are 

 distinct, under every aspect, from the grey gneiss, set in on the west, 

 and are well seen near the farm of Glanmorfa. Passing south of 

 Hafodty the two are seen on the opposite sides of the farm, the area 

 of the former broadening out. Continuing the line thus indicated, 

 though it is lost beneath the sands of ISTewborough Warren, we notice 

 that it runs to the west of all the visible bosses of the schistose 

 diorite. On the east of the line, where the road to Bodorgan starts 

 across the marsh, is a quarry of reddish-purple slate, in which no 

 crystallization has taken place ; and similar reddish-purple slates occur 

 in the hills and hollows behind Y Rholdy, and darker ones on the 

 shore at that spot. Further south, we pass, by an unbroken sequence 

 traceable all the way, through schistose ashes into the remarkable 

 rocks now about to be described. Since the succession thus noted 

 does not correspond to that on the north-east, since there is no 

 sign of an anticlinal in the Llangafi'o cutting, but rather the reverse, 

 since the change in the rocks is rapid, and since the new rocks 

 belong more to the central facies than to the eastern, I judge that 

 they are cut off by a fault and thus correspond to the outlier on the 

 north. 



On the Survey map are marked some narrow bands of " green- 

 stone " cutting across the cliff, and apparently less important than 

 those on the other side of the bay at Dinas Llwyd. At the latter 

 place we seem to be on the outskirts of an eruptive area ; but here 

 at Careg Gwladys we reach the very centre, and are reminded of 

 the beautiful phenomena of Pen-maen-melyn near St. David's, which 

 are here surpassed. The rocks are exposed in a series of what may 

 be called buried cliffs and stacks, once washed and laid bare by the 

 sea, but now covered with the drifting sand, which has rendered 

 J^ewborough Warren as remarkable for its rabbits as for its grass - 

 made brooms and mats. The bosses which here and there stand 

 uncovered provide all that is needed by the geologist. 



The first rock that we notice is a massive green one, which 

 becomes more important as we pass on, till in a low mound on the 



Fig. 17. — View of Rock at Careg Gwladys. 



2 1 2 1 



1. Diabase. 2. Limestone-slate. 



level ground we find it surrounding and running in bands across 

 a purple rock, the two so intimately blended that they seem but 



