1858.] . MUECHISOX — SANDSTONES OP ELGIN. 431 



is a lithological feature common to the whole series and strongly to 

 be dwelt upon. It is, however, to be remarked that the cornstones 

 of the shore to the west of Lossiemouth, and the patch at Inverugie, 

 are much more cherty than those beds which, lying further to the 

 south, occupy an inferior position. The uppermost or third zone of 

 cornstone is indeed distinguishable from either of the others, in being 

 highly mineralized and siliceous, containing veins of pure lead-ore, 

 whilst the central cornstones are massive limestones, and the lowest 

 (thin, small, and mottled red and green) concretionary earthy lime- 

 stones ; still they are all referable to varieties of cornstone. But, 

 after all, the presence of cornstone is j^er se no proof that the sand- 

 stone in which it occurs is the Old Bed Sandstone ; for the rocks first 

 described as cornstone by Dr. Buckland in parts of "Worcestershire 

 and Staffordshire were afterwards shown by myself to be of the 

 Lower New Eed age (or what I have since named Permian) *. (See 

 * Silurian System,' p. 55, pi. 37.) 



Looking to the persistent strike of all these arenaceous deposits 

 from their red bases to their yellow and white summits, — to their 

 interlamination and association with cornstones at low and high 

 levels, — ^to the ascent from the beds with Caithness fishes to the strata 

 laden with IIolo]^tychii, and fi'om the latter into the upper or reptili- 

 ferous masses, — to the gentle undulations and low dips to which, 

 from the base upwards, they all conform, — I was led to the conviction 

 that, to however high a family of Eeptiles the Stagonolepis might be 

 referred, both the yellow sandstones of Elgin and those of the coast- 

 ridge would seem to belong to the same geological group of strata 

 as the underlying Eed Sandstone. 



In prolonging the survey from Morayshire into Banffshire, we find 

 that the upper or yellow sandstones have been partially prolonged 

 to the sea-coast only, and that in the interior, the deep-red sand- 

 stones and conglomerates represent the middle and lower parts of the 

 series, which have recovered the large dimensions they possess in 

 Eoss-shire and the northern counties. On the banks of the Eiver 

 Spey vast thicknesses of deep-red sandstone and conglomerate (fine 

 types of which are seen at the Bridge of Fochabers) are overlaid at 

 Dipple and Tynet-burn (near the mill) by argillaceous courses with 

 nodules containing certain fishes of the genera Pterichthys, Coc- 

 costeus, Glyptolepis, Osteolepis^ CheiracanthiiSf Biplacanthusf, &c.f a 

 complete Caithnessian assemblage. 



Again, at Gamrie, near Troup Head, Aberdeenshire, where the 

 central zone reappears on the sea-coast replete with the same group 

 of fishes, the beds are seen to be underlaid towards the interior of 

 the county by vast masses of deep-red sandstone and conglomerate. 

 In that tract the yeUow sandstones are no longer visible, being 

 buried imder the German Ocean. 



■ * The reader who may refer to the 'Silurian System' will see, in the foot-note 

 at p. 55, that in the first year of my sm.*vey I was misled by the mineral charac- 

 ters, and was disposed to consider those sandstones with cornstones to be of 

 Old Eed age. 



■ t Fine specimens of these ichthyolites were presented to me by Mr.. Alex. 

 Simpson, of HoU, Tynet. 



VOL. XV. PAET I. 2 I 



