of the Birmingham and Gloucester Railway. 551 



but too imperfect to exhibit generic characters*. In the hill south of Dunham- 

 stead is a fault which causes the grey marl to abut against the red, as seen in the 

 Railway section, sheet 17, and PI. XLVIII. fig. 3. of this volume. 



For the next five miles the railroad runs through red marl in a valley between 

 the escarpment of the lias and a ridge caused by the " Keuper sandstone." On the 

 south-east of Spetchleyf is a dislocation which causes the Keuper sandstone to 

 change its strike from south by east to south-west, forming a projecting angle which 

 is intersected by the railroad. The stratum is here but a feeble representative of 

 the Keuper sandstones of Burg Hill, Inkberrow, and ShrewleyJ, consisting chiefly 

 of greenish marl with thin laminae of white sandstone, the whole forming a deposit 

 of about twenty feet thick, with red marl both above and below\ The bands of 

 sandstone vary rapidly in thickness, and one wedge-shaped solid mass, about thirty 

 feet long, is two feet thick in the middle, and thins out entirely at each end. 



§ 3. Lower Lias. — About a mile further south, at Norton §, the railway traverses 

 the lias escarpment, which presents a section exactly analogous to that at Dunham- 

 stead, showing the same succession of lias-limestone, clay, white thin-bedded sand- 

 stone, grey marl, and red marl. The sandstone also contains the oval bivalve 

 met with at Dunhamstead. 



About a mile south of this point, the lias clay contains many calcareous con- 

 cretions abounding with shells, including Plagiostoma giganteum\\, P. duplicatum, 

 P. Hermanni, Goldf., Terebratula ornithocephala, Modiola minima, and a Caryo- 

 phyllaa, which is remarkable from the general scarcity of corals in the lias for- 

 mation. Further south, near Abbott's Wood, the beds of fissile sandstone at the 

 base of the lias are again exposed on the railway, being brought up by a fault. 

 Thence the lias clay presents little interest till we reach DefFord (PI. XLVIII. fig. 5.), 

 where numerous specimens oi Pachyodon% Listeri (Stutchbury, Annals Nat. Hist., 

 March 1842) {Unio Listeri, Sowerby), Gryphcea incurva, Astarte lurida, Plagio- 

 stoma punctatum, P. duplicatum, and several apparently new species of Ammonites, 

 Modiola, &c., occurred in the cuttings. 



The same shells are found also at Eckington (fig. 5.), on the south of the Avon ; 

 but at Bredon (fig. 5.) we reach a higher stratum of the lias clay, and meet with 

 an almost entirely distinct set of organic remains, among which Pleurotomaria 

 Anglica, Hippopodium ponderosum, Gryphaa Maccullochi, Nautilus striatus, Phola- 



* In a paper read December 1841, 1 have shown that this band of sandstone is the true equivalent of 

 the " Bone-bed" of Somerset and East Devonshire. Note, 1842. 



t See sheet No. 14, and Plate XLVIII. fig. 4. 



X See Geol. Trans. 2nd Series, vol. v. p. 332 ei seq. § See sheet No. 13, and Plate XLVIII. fig. 4. 



II All the shells included in this and the following lists are described in Sowerby's Mineral Concho- 

 logy, unless a different authority is given. 



f The name Pachyodon having been previously used by Von Meyer for a vertebrate genus, should 

 here be superseded by the term Cardinia of Agassiz. 



4b2 



