Dr. FiTTON on the Strata below the Chalk. 



239 



whole of their calcareous matter has disappeared *. This is the more 

 remarkable, as in many other places, indeed generally, the fossils of the 

 green-sands consist of carbonate of lime ; the absence of which, however, 

 is prevalent throughout the sand of the Blackdown Hills, which seldom 

 effervesces with acids ; and to this circumstance, probably, the excellence 

 of the concretions which they contain, as a material for whetstones, is to be 

 attributed. 



A very extensive collection of fossils from the Blackdown pits was formed 

 by the late Mr. Miller, of the Bristol Institution ; and is now in the museum 

 of that establishment. The Managers were so good, at my request, as to allow 

 the whole of this valuable collection to be sent to London, where it was 

 examined by Mr. Sowerby, by whom the subjoined list, and the annexed 

 plates, have been prepared : and I have great pleasure in expressing my 

 obligation for this mark of their confidence and favour. 



(123.) List of Fossils from the Sands of Blackdown, and of some other 



places in Devonshire^. 



Ammonites auritus. M. 



A — denarius. A thin crust of hydro- 

 phanous chalcedony, over spongy sili- 

 ceous stone. M., Min.Con., F. 



A — dentatus. M. 



A — falcatus. M. 



A— Goodhallii. Blackdown. M.,F.,Min. 

 Con. Near Lyme. D- 



A — Hippocastanum. Dowlands cliff, 

 near Lyme. Min. Con. 



A — lautus. M. 



A — splendens. Pinhay, in hard green 

 sparry stone. F. 



^— triserialis. PI. XVIIL f. 27. Mr. 

 Sowerby's museum. 



A — iuherculatus. M. 



Ammonites varians. A gibbose variety. 



M. Pinhay. F. 

 A — varicosus. M., F. 

 A — Another species, probably new. 



M. 

 ^»z^/«rfeswz«tenuistriatura. M. Pl.XVI. 



f. 7. 

 Area rotundata. M. PI. XVII. f. 8. 

 Astacus, Portions of. Pinhay. Miss An- 



ning. Near Lyme. D. 

 Astarte concinna. PI. XVI. f. 15. M. 



Mr. Sowerby's museum : D. 

 A — cuneata . F. 



A— formosa. M. PI. XVL f. 16. 

 A— impolita. M. PI. XVI. f. 18. 

 A — lineata. F. 



* See Conybeare ; "Outlines," &:c., p. 128. 



f All the Fossils in this list are from the Whetstone Pits at Blackdown, except those to which a 

 different locality is assigned : and all the specimens from the Blackdown pits, where a different 

 composition is not mentioned, are casts in chalcedony. 



The letter M. denotes that the specimen is from the collection of the late Mr. Miller, now in 

 the museum of the Institution at Bristol : Min. Con. refers to Mineral Conchology : D. to a paper 

 of De la Beche, on the chalk and sands in the vicinity of Lyme Regis and Beve ; Geol. Trans. 

 2nd Series, vol. ii. p. 109 et seq. : F. to the Author's Collection. 

 VOL. IV. — SECOND SERIES. 2 I 



