328 ME. 0. A. SHRUBSOLE ON TRIASSIC PEBBLES OE [Aug. I903, 



Trias, as a whole, has a general north-to-south range. "With 

 regard to the Bunter Pebble-Beds, some old lines of connection may 

 have been rubbed out ; but we may reasonably infer some relation- 

 ship when we find so many features in common. To take, for 

 illustration, the case of the trilobites. Pour species, all Norman 

 types, have been found at Budleigh Salterton ; three of these have 

 already been found in the Midland pebbles, and no others. 



Again, Orthis hudleighensis is the commonest fossil in the Ordo- 

 vician pebbles of Budleigh Salterton ; it fills of itself whole beds at 

 May, Jurques, Campandre, and Mont Robert. 1 It has been found in 

 derived Bunter pebbles in the Pleistocene gravels by Mr. S. Gr. 

 Perceval, at Sparkbrook, near Moseley ; by Mr. W. J. Harrison, at 

 Countesthorpe, near Leicester ; by the late Mr. Vaughan Jennings, 

 near Nottingham ; by the late Rev. P. B. Brodie, near Warwick ; 

 and by Prof. Bonney, near Rugby. The present writer, moreover, 

 has found it in the neighbourhood of the Lickey and in the gravel 

 of the Thames Valley. 



Again, the occurrence of so distinct a fossil as Lingula Lesueuri in 

 all three districts is very significant. 



Even if there should prove to be an uncertain or undetermined 

 element in the Midland pebbles, whether found in the Bunter 

 itself or derived, the correspondences which have been shown to 

 exist must be accounted for. 



There is, in fact, a distinct element in our older river-gravels, 

 which does not come from the Bunter, and yet is not strictly local ; 

 but, beyond noting the fact, we have nothing to do with this 

 at present. 



VI. General Conclusions. 



The result of my own observations has been, in the first place, to 

 confirm Salter's opinion that the Budleigh-Salterton pebbles came 

 chiefly from Normandy, or some land connected therewith. The 

 subsequent determining of a considerable number of Devonian 

 brachiopoda from the same pebble-bed, almost all of them being 

 non-British types, appears to be of significance only in so far as it 

 suggests that the Devonian and the Ordovician rocks cannot have 

 been very far apart. 



The Ordovician fauna is found to vary locally. In particular, 

 the types are different north and south of the barrier indicated 

 by Barrande. The fauna of the Calvados district is the most 

 nearly related to that of the Budleigh-Salterton pebbles. We have 

 seen that that district was probably undergoing erosion at the 

 epoch of the Bunter Conglomerate. Indeed, the same thing 

 may be said of the whole Armorican massif, which probably 

 extended across what is now the Channel into part of the British 

 area. This massif may have been mountainous at that time or 

 not, — it is said by Prof. Bonney to have been broader than, if not 



1 Gr. de Tromelin, Bull. Soc. Linn. Norm. ser. 3, vol. i (1877) p. 65. 



