ROCKS OF SOUTH DEVON. 503 



a nature, and involve so close a study of local relations, that T must 

 here merely confine- my remarks to general conclusions as to the 

 formation and occurrence of the limestones of South Devon, without 

 presenting the innumerable local observations on which those con- 

 clusions are based. 



3. Middle- mid Upper-Devonian Limesto7ies. — The massive lime- 

 stones of Woolborough and Lummaton are so well known through 

 Mr. Whidborne's researches that it will be unnecessary to give fossil- 

 lists ; Dr. Kayser correlates the Lummaton shelly limestone with 

 the upper part of the Middle Devonian. From its massive nature 

 the structure of the Lummaton limestone, as also that of Barton, 

 which I correlate with it, is not apparent. The Brachiopod fauna 

 occurs in a verjr restricted space, and the rock is there very similar 

 to parts of the Ugbrooke-Park and other limestone masses on the 

 border-land between the Middle and Upper Devonian. 



The upper part of the Kingsteignton mass, &c., the massive lime- 

 stones of Chudleigh, Ugbrooke Park, Oldchard, and Ideford belong 

 to the same general group, as also a considerable part of the 

 Kingskerswell mass. 



The limestones of Barton and Lummaton are coralline masses, 

 Alveolites, Stromatopora, and other common forms being associated 

 with Smitliia. In the Barton quarries, Clioaopliyllum perfoliatum 

 is common, and this form occurs in the Pamsleigh limestone *, 

 associated with Acervidaria pefitagona. 



A part of the Barton limestone is a coral-breccia recemented ; and 

 in one nearly vertical fissure or fault the fragments also appear 

 rolled. Whether this phenomenon is due to surf-talus banked on a 

 mass of coral-growth or not, I leave to the judgment of those better 

 qualified to form an opinion. 



North of the Woolborough quarry, in Langs Copse, I obtained the 

 following : — 



Athyris. I Rhynchonella pugnus. 



Atrypa desquamata. | Strophoaiena rhomboidalis. 



Duboisi. I Alveolites. 



Rbynchonella cuboides. j Heliolites porosus. 



Mr. Champernowne, in unpublished notes, mentioned his discovery 

 of " a fine example of RJujnchonella cuboides at Ramsleigh " ; and 

 further, " Wiynclionella cuboides^ in Devonshire, is most abundant 

 at Woolborough quarry and Lummaton hill, near Torquay, both of 

 which contain occasional String ocephali " . . . . " Either the first 

 shell lived earlier in Britain than on the Continent, or the Stringo- 



* Witli reference to this we find tbe following query in Mr. Champernowne's 

 unpublished notes: — "Is not the so-called Chonopliyllum 'perfoliatum, E. & H., 

 of Ramsleigh, more allied to the genus Ftychopkyllum ? Milne Edwards and 

 J. Hainie state that it has neither columella nor walls. The latter I admit; but 

 the central area, either in horizontal or vertical sections, consists of densely 

 twisted plates (very like what occurs in Pfychophylhcm). The outer part of 

 the expansions of which the coral is made up is rounded, plicated, and slightly 

 granulated on the surface, which expansions, as they near the true central 

 depression (calice), are crested by a septal ridge." 



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