| 1. | Upper Lias shale, full of saurian remains, belemnites, ammonites, &c. intercalated with the lowermost beds of the Oolite: nodules and beds of limestone. |
| 2. | Lias marlstone; calcareous, sandy, and ferruginous strata, very rich in terebratulæ and other marine shells. |
| 3. | Lower Lias clay and shale, abounding in gryphea incurva, and other marine shells; intercalations of sands and clays, with nodules of limestone. |
| 4. | Lias rock; a series of laminated limestones, with clay partings. Bone-bed, with numerous remains of fishes. |
Obs.—The Lias is the grand depository of those tribes of marine reptiles, the Ichthyosauri and Plesiosauri, whose remarkable forms, structure, and state of preservation, have excited the attention even of the most incurious. The collection of these remains in the British Museum, principally formed by Mr. Hawkins, is unrivalled.[19]
[19] See "Petrifactions," p. 337-367.
The Trias; or New Red Sandstone Formation,[20] (Wond. p. 533). This group of rocks consists of variegated marls, sandstones, and conglomerates, frequently of a red colour, with marine shells, crinoideans, fishes, and reptiles; marine and terrestrial plants. This series contains extensive deposits of rock-salt, and brine-springs.
[20] Called by some geologists Poikilitic (variegated) group.
This formation comprises the Trias, or triple group, viz. the Keuper, Muschelkalk, and Upper Bunter Sandstein, of the German geologists.
Subdivisions:—
| 1. | Variegated red, blue, and white marls, and shales, with gypsum and beds of rock-salt. (Marnes irisées of the French.) |
| 2. | Variegated red and white sandstones. |
| 3. | Conglomerates formed of the detritus of the older rocks. |
| 4. | Bed mottled sandstone, and marls. (Grès bigarré of the French.) |
Obs.—To this formation belong the principal deposits in Leicestershire and other midland counties of England. Fossils are not generally abundant, but some localities yield highly interesting remains. The shelly limestone of Germany, called Muschelkalk, which contains the Lily Encrinite, &c. does not occur in England. Remains of Conifers allied to the Yew and Araucaria, are found near Coventry; and peculiar reptiles (Labyrinthodons) near Warwick.