ON THE DEVONIAN AND SILURIAN BRACHIOPODA THAT OCCUR IN 

 THE TRIASSIC PEBBLE-BED OF BUDLEIGH-SALTERTON, NEAR 

 EXMOUTH, IN DEVONSHIRE. 



Before commencing the Devonian and Silurian Supplements it has been thought 

 desirable to treat separately of a large series of Brachiopoda belonging to those periods, 

 but of which the greater number of species have not hitherto been found in rocks in 

 situ in Great Britain. These fossils occur in sandstone and quartzite boulders or 

 pebbles that have been drifted from some distance, accumulated, and spread over a 

 considerable tract of country in the neighbourhood of Budleigh-Salterton. The source 

 of derivation of these pebbles is still a matter of speculation, but they were without doubt 

 drifted during the Triassic period ; and we propose to lay before our readers the present 

 state of our knowledge on this difficult and interesting subject. 



At page 355 of his work, 'The Student's Elements of Geology' (ed. 1871), Sir 

 Charles Lyell gives the following well-known nomenclature of the Trias, the upper and 

 lower divisions alone of which are represented in Great Britain. 



German. French. English. 



Keuper. Marnes irisees. Upper Trias — Saliferous Shale and Sandstone. 



Muschelkalk. Calcaire coquillier. Middle Trias — wanting in England. 



Bunter Sandstein. Gres bigarre. Lower Trias — Sandstone and Quartzose conglomerate. 



The boulders, in which the species of Brachiopoda I am about to describe occur, vary 

 considerably in shape and size, being both rounded and flattened ; and at my request 

 Mr. H. J. Carter, F.R.S., of Budleigh-Salterton, has kindly drawn up a detailed account 

 of the different kinds of pebbles that occur in this now well-known locality. This will 

 be found to convey all the information that could be desired. 1 It is, however, with the 



1 " The Cove of Budleigh-Salterton is about two and a half miles long, confronted by a narrow 

 pebble beach, bordered by the sea on one side, and for the most part by high cliffs of the New Red Sand- 

 stone series, capped by a thin detrital layer of the flinty remains of the Cretaceous, which formerly overlaid 

 it, on the other. The pebbles of this beach, which are derived from the sources just mentioned, are of all 

 sizes below a foot in diameter ; and from the prevalence of the south-west wind on this coast, they are 

 chiefly gathered together at its eastern end, although kept from extending further on either side by the 

 presence of reefs of New Red Sandstone conglomerate projecting into the sea. 



"Looking at the cliff from tbe sea, we observe that it may be divided into three distinct portions, 



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