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Gypseous series in other localities, {example, Aust and Westbiiry,) 

 or they may even be the representatives of the Rha;tic beds, 

 under different physical conditions, and in an unfossiHferous 

 state. It is these Red and Yellow Marls that have been, or 

 appear to have been, mistaken for the Permian beds — chiefly, 

 perhaps, from their coloui- and Magnesian Marl-like condition, 

 but more particularly from the mistake which has evidently 

 arisen through fossils having been collected from the yellowish 

 Limestones below them, but which fossils unmistakeably belong 

 to the Carboniferous Limestone. 



The mistake seems to have occurred from the (local) absence 

 of the Red beds (below the Yellow) at the Railway Station, and 

 the immediate superposition of the Upper Yellow Sandy Marls 

 upon the yellowish coloured Carboniferous Limestone, and 

 a want of care in discriminating between the two, although 

 perfectly nonconformable one to the other. Long ago it was 

 stated by Mr. Eassie that he had collected from these YeUow 

 Marls (?) numerous fossils, called Permian. This fact he long 

 ago mentioned to Mr. Jones, myself, and lately to 'Mx. Bkistow, 

 of the Geological Survey, who visited the section this summer, 

 and collected a few fossils (Terebratulse.) Mr. Bkistow seems 

 also to have failed to detect the exact position of the fossils, 

 or the nature of the Marls and Sandstones, vnth relation to 

 the Carboniferous Limestone upon which they rest. The latter 

 gentleman forwarded to me several specimens of Terebratulse, 

 which at first sight strongly resembled T. s^ifflata, from the 

 Permian beds of Northumberland, &c., or dwarfed varieties of 

 the well-known T. hastata, from the Carboniferous Limestone. 

 These were submitted to Mr. Davidson, who would not decide 

 as to their exact species for the want of better specimens, 

 although he at once admitted that they had close aflSnity with, 

 and strongly resembled, the Carboniferous hastata. These 

 doubts determined me to visit the section, and examine into its 

 physical structure, as well as fossil contents. The result was 

 that the so-called Permian fossils do not come from the Yellow 

 Marly Magnesian Sandstones, but are from Red and Yellow 

 beds of Carboniferous Limestone age, which exist immediately 



