MR. PRESTWICH. 
127 
instead of belonging to a period which no 
human eye witnessed, and no human hand 
recorded. 
The alternations in the coal strata will be 
more easily understood from a statement of 
their actual contents, as they have been 
wrought for economical uses, and carefully 
described. 
The following is from an elaborate me¬ 
moir by Mr. Prestwich, on the geology of 
Coalbrook Dale, and embodies the result 
of very numerous observations made in all 
parts of that district. 
I. Terrestrial strata, containing remains of 
land, plants, calamites and ferns. 
II. Marine and Flumatile, Shells of Lep- 
trnna, Conularia, and fragments of a 
fish Megalicthys. 
III. Terrestrial and Fluviatile, Stems of 
Lepidodendron, fern leaves, shells of 
Unio an estuary creature. 
IV. Marine and Flnviatile, Fishes and 
shells of Lingula. 
V. Terrestrial. Coal with stems of Lepi- 
dodendron. 
\ I. Marine, Terrestrial and Fluviatile, Iron¬ 
stone. Seashells, River shells and plants. 
