Queries and Anstvers, ^95^ 



tacea, and it is distinguished no less by the profusion of these remains, than 

 by the variety of their species, and the beauty of their preservation. Its 

 site is upon the western extremity of the green sand formation, where it is 

 prolonged or protruded considerably beyond its general hne of escarpment, 

 and forms extensive out-lying masses ; amongst which the elevated table- 

 land of Blackdown is conspicuous. 



The fine state of preservation of 

 the fossils of this district is owing 

 to the subtitution of chalcedony for 

 the calcareous matter of the shells ; 

 by which singular process all the 

 delicacy and characters of the ori- 

 ginal are preserved, in a much less 

 destructible material j nothing being 

 requisite to complete the copy but 

 colour. Those with which we have 

 been favoured by our correspon- 

 dent belong to the following ge- 

 nera: Turrit^lla, A'rca, Cucullae'a, 

 Trigonia, Cardium, Pectunculus, 

 V^nu5, Corbula, Chama, Inoc^ramus, 

 and Ammomtes, with an Echinite. 

 They are the most prevailing of the 

 green sand fossils. 



As it forms part of our plan to 

 illustrate the geology of our island 

 by catalogues and sketches of the 

 most characteristic forms in the re- 

 spective formations, it will perhaps 

 be advisable to postpone the draw- -^ 



ings of the Blackdown fossils, until they can be more appropriately intro- 

 duced in the course of our geological articles. Meanwhile, we figure one 

 of those bodies (^g. 82.) which are conjectured by our correspondent to be 

 fruit, but which, in fact, are zoophytes, originally bearing the name of Tulip 

 -<41cy6nia, and now placed under the genus Siphonia. Some interesting 

 illustrative figures of this zoophyte may be seen in Geol. Trans., vol. ii. 



Mr. Parkinson describes it as a fossil animal, with a polymorphous body 

 supported by a stem proceeding from a fusiform or ramose root-like pe- 

 dicle ; the original substance spongious, and pierced by a bundle of tubes 

 derived from the pedicle, passing through the stem, then ramifying and ter- 

 minating on the surface of the body, 



With the other fossils from Blackdown are obscure spongiform spherical 

 bodies, which must have existed in great abundance at the same time with 

 the Testacea. 



There are some other varieties of zoophytes, and numerous shells, besides 

 those now furnished, which occur in this rich depository of organic remains. 

 Contributions like these are highly estimated ; they enlarge our acquaint- 

 ance with the products of diiFerent districts, and will, moreover, much faci- 

 litate the object we have in view of furnishing an outline of English geology, 

 derived, as much as possible, from original sources. 



We cannot expect collectors to contribute specimens of rarity or of value, 

 but there are districts where they are so readily attainable, that the geolo- 

 gical student would often find it preferable to furnish originals, as in the 

 present instance, than the drawings with which we have been favoured. — 



R. a T, 



The Packet of Fossils sent by Samuel Tyssen, Esq., of Narborough Hall, 

 Norfolk, are, with one or two exceptions, casts of chalk fossils in flint, and 

 have apparently been collected from the surface of the soil, or from the loose 



