Limestones of South Devon. 725 



mine in having promoted the new classification. (Lond. and Edin. Phil. Mag., April 1839 ; ante, 

 p. 688.) 



It is not necessary to offer any remarks on the papers which have been read to the Society, or 

 have been published since those last noticed ; and I have forborne alluding to the memoirs 

 on North Devon by Mr. Weaver and the Rev. David Williams. It is requisite, however, to state, 

 that Mr. James Sowerby, from his first inspection of the Bradley fossils to the promulgation of 

 the old red or Devonian classification, considered the limestones to belong to the true carboni- 

 ferous series. 



Such is my brief summary of opinions respecting the age of the limestones 

 south of Dartmoor; and I have confined the extracts solely to them, because 

 I alluded to them alone, when 1 threw out the suggestion respecting their 

 age. I then knew little of the structure of Devonshire, and great was my 

 surprise when told by Prof. Sedgwick and Mr. Murchison of their bold re- 

 moval of the whole of the schistose and greywacke rocks of that county and 

 Cornwall, to the old red sandstone— a generalization which could only arise 

 from long, patient, accurate, and extensive practice in the field ; and a 

 willingness to adopt a suggestion from whatever quarter it might be ad- 

 vanced. 



Three of the foregoing memoirs claim a few remarks ; namely, Mr. De la 

 Beche's on Tor and Babacombe Bays ; Mr. Prideaux's on Plymouth ; and 

 Mr. Phillips's article in the Encyclopaedia Metropolitana. It will be most 

 convenient to take Mr. Prideaux's communication first. 



That gentleman's inference of the age of the sandstone associated with the 

 limestone was clearly deduced from mineral characters ; yet full credit must 

 be given to him for placing part of the limestones in the old red sandstone. 

 He says nothing respecting the zoological evidence, though acquainted with 

 Mr. Hennah's collection of fossils; and he considered the Plymouth limestone 

 might be a different formation from the Torbay. 



Mr. De la Beche's memoir on Tor and Babacombe Bays contains a list 

 of twenty-one species of fossils, determined by Mr. James Sowerby. It was 

 of great value as the first attempt to define the zoological characters of the 

 Devonshire calcareous rocks. In the list, two mountain-limestone species, 

 Cardium aliforme, (believed by the author of this notice to be a distinct 

 species) and Bellcrophon tenuifasciata, were positively identified, and two 

 doubtfully, Spirifera rotundata, and Pleurotomaria carinata ; and of the re- 

 mainder, eight were considered to be new or found only in the Devonshire 

 limestones, and nine too indistinct to be named specifically. The amount 

 of evidence in this list in favour of the Torbay limestones being of the age 

 of the carboniferous series, was very small ; yet in the absence of the Trilo- 

 bites and other fossils of Dudley, at that time considered proofs of the transi- 



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