By Mr. Cunnington, F.G.S. 



3 



at least 4850 feet since the Bradford clay period, we may thus 

 arrive at some conception, though but a feeble one, of its extreme 

 antiquity. 



Geologists are very generally agreed that the Bradford clay 

 ought not to be considered as distinct from the Forest marble, and in 

 the geologically coloured sheets of the Ordnance Map lately issued, 

 no distinction is made between the Bradford clay and the Forest 

 marble; it is in fact considered as part of the latter stratum. On 

 this subject Mr. Lycett, whose valuable contributions to the Pal- 

 aeontology of the British strata are so well known, has favoured 

 me with a note in which he expresses his opinion, that the term 

 Bradford clay considered as a distinct stratum does not apply to 

 Gloucestershire. 1 Nevertheless as indicating the lower clayey 

 portions of the Forest marble, in which great numbers of the 

 Apiocrinites are usually found, the name Bradford clay is for con- 

 venience sake still retained. 



The Bradford clay of Wiltshire is confined to a band on the 

 north-west of the county, but it is most extensively developed near 

 this town (hence its name), and here the fossil remains are the 

 most interesting. Mr. Lonsdale says, "It appears forming a thin 

 bed in the neighbourhood of Yatton Keynell and Giddy Hall, but 

 between the latter point and Berefield, near Bradford, it is want- 



1 Mr. Lycett says, " The bands of clay and marl which occur throughout the 

 Forest marble and upper portions of the Great Oolite" (in Gloucestershire) "are 

 extremely irregular and little persistent; so much so that in draining it rarely 

 happens that a bed can be followed 200 or 300 yards, however important it may 

 appear in some parts of its course. None of these clay bands have produced 

 Apiocrinites as far as I am aware, and I only know of two places which have 

 produced Terebratula decussata ( coarctata ) and Terebratula digona (see wood- 

 cut at page 5) ; Avicula costata and Avicula echinata have a vertical range too 

 considerable to be of any use. Decapitated stems of Apiocrinus are not uncom- 

 mon in the upper limestones (the upper zone of the Great Oolite, with Pachy- 

 risma grande, of Mr. Hull). From the top of these white limestones to the 

 Cornbrash there is no clear lithological division, and for a zoological division I 

 think that none can be made between the lower beds of the Great Oolite and 

 the base of the Cornbrash." 



My friend Professor Buckman of the Royal Agricultural College, says, 

 "There can be no objection to include the Bradford clay with the Forest mar- 

 ble, of which indeed it may be said to be the fossiliferous bank of deposit ." 



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