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DR. C. A. MATLEY ON THE 



[Aug. 1908, 



coarse deposit, formed of subangular and rounded pieces of the 

 Silurian rocks of the district. It extends along the shore, dipping 

 at low angles, for about a quarter of a mile. Its thickness is esti- 

 mated by the Geological Survey at about 200 feet,^ and, judging 

 from the dip of the beds and the extent of the ground which they 

 cover, this estimate appears to be substantially correct. 



This deposit succeeds the pebble-bearing limestones rather 

 abruptly, and in its lowest beds large, boulder-like, rounded masses 

 of Carboniferous Limestone are abundant, the matrix being also of 

 limestone; but, so soon as the lowest beds are passed the remainder 

 of the Conglomerate is found to be a great mass of almost uniform 

 coarseness (fig. 14). The included blocks are of the same character 



Fig. 14. — Lane Conglomerate. 



as those found in the Eush Conglomerates, and range up to the 

 same maximum size. Many are more than 2 feet in diameter, 

 one measured 33 x 22 x 15 inches, another 42 x 30 inches. The 

 great majority of the inclusions have clearly had their origin in 

 the Silurian rocks of the neighbourhood ; pieces of a red pebbly 

 sandstone occasionally present may, however, have been derived 

 from the Old Red Sandstone. 



^ Expl. Sheets 102 & ] 12, Mem. Geol. Surr. Irel. 2nd ed. (1875) p. 65. The 

 thickness, 80 feet, given in fig. 19 of that Memoir (p. 62), appears to be merely 



a clerical error ; possibly 180 feet 



itended. 



