OTOLOGY. 



GEOLOGY. 



8.8 



Strict of BrMtk Strata, beyunting at tht Surface, from tcAiVA all Waler-ifored Gravel and Rivtr Sedimenti are nppottd to be remored. 

 Tb* Marine Strata art marked by Figure* ; the Freeh-Water and .Estuary Beda by Letten ; the names of tome cbaracterUUe Fossils are In Italics. 



TERTIARY STRATA. 



(A small number of the Fossils are identical with existing species.) 



Name* of Formation*. 



General Thickness. 

 Yards. 



Fresh-Water Marls 

 ( London Clay 



| Plastic Clay 



Remarks. 



I. CUy 16 



. . S3 



100 to 200 



100 to 400 



\ water-drifted mass of marine shell., pebbles, Ice., resting on more regular shelly beda of 

 annd or sandy limestone. About 40 per cent, of the shells are supposed to be identical 

 with existing species. 



They Include a bed of (estuary shells, and occur only in the Me of Wight, 

 Maaa of clay rich in marine ahells, of which Si per cent, are identical with recent kinds. 



{Variously coloured sands and claya, the latter containing organic remaina identical with, or 

 much allied to, those of the London clay. 



8ECOXDARV STRATA. 



(All the Fossils belong to extinct species. They are different from those in the Tertiary Strata.) 



3. Chalk . 



4. Greeenaand 



rith interstratiBcd flinla ; extinct Zonphyla, 



. Weolden '. 

 i. Portland Oolite 



. Oxford Oolite 



7. Bath Oolite (near Bath) 



( Of unequal hardness, soft above, marly below, 

 ( Ananchytrt, and other Eehinodfrmata. 



! Upper Greensand, very fossiliferous, in general chalky. 

 Gault, a blue marl, or clay, often very fossiliferous. Relemnittt minima. 

 Lower greensand, or iron-sand, very fossilifcrous in places. 

 Weald clay, with fresh-water shells. Cypridrt. 

 Hastings sands, with land-plants, and bones of Iguanodrm. 

 Purbcck beda of .clay and limestone, with fresh-water shells. 

 A variably locally oolitic limestone ; some beds full of fossils. 

 Kimmeridfre clay, with layers of Oitrea drltmdta. 



300 



130 



8. Liaa 



150 



130 



350 



v 



i 



9. New Eed-Saadatone 



10. Magneslan Limestone 



100 







c. Coal 



1000 



11. Carboniferous or Mountain-Limestone . . BOO 



11. Old Ked-Sandstone . . . . 100 to 8300 



| Upper calcareous grit. 



' Coralline oolite, with beds and masses of coral; Ectiinida; many shells. 

 Lower calcareous grit. Ammonite* catena. Pinna laneeoiata. 



! Kefuwa Cl *rock } AmmmUa Oallotifmii, Oryphaa dilatata. 



Combrash, thin, impure, shelly limestone. Aeiculn echinata. 



Forest marble. Shelly oolite, with concretionary sandy limestone. 



Bath oolite. In several divisions, shelly, oolitic, compact, and sandy beds. Jfegalotaurui, 

 Apiocrinux, 



Fullers'-earth. A scries of calcareous and argillaceous shelly beds. 



Inferior oolite. Fholadomya. Trignnia ttriata. 



Hand, with concretionary masses holding shells. 

 f" Upper lias shale. Full of characteristic saurian*, of Ammonite*, flelemnitet, and other shells. 



Marlstone, replete with Trrebrntula, Pectinida, Arirula imrquiralrii, 

 I Middle lias shale. Contains Gryphtta, Ammonitet. 



Lias limestone, with O'ryphaa incurra, Ammonitet Oonybeari. 

 I, Lower lias shale and coloured marls. 



Coloured marls, gypsum, and rock salt. } 



Kcd and white sandstones and marls. > Few or no organic remains. 

 Conglomerate and sandstone. 



Knottingley limestone. A few bivalves in the lower beds. 

 Gypseous red marls. No fossils. 

 Mniroesian limestone. Shells, corals. 

 Marl slate. Fishes of remarkable forms. 

 ! Ked-sandstonc. Plants of the subjacent coal series occur in it. 



The subdivisions of the coal series are only locally ascertained. Gritstone and shales eontitute 

 the principal mass. Flagstone and iron-atone arc among the most characteristic b< 

 Fresh-water limestone and marine limestone are exceedingly rare and local. The shells are 

 mostly of irsluary origin. The plants arc mostly of terrestrial tribes and extinct v 

 f Millstone grit, series of sandstone, shales, cool, and thin limestones, forming a transition 

 group between the coal and the carboniferous limestones. 



Yoredalc rocks, consisting of five or more beds of limestone, with alternating flagstones and 

 other gritstones, shales, thin coal, iron-stone. 



Lower or scar limestone, In the north of Kngland and Scotland, subdivided by sandstones, 

 shales, and coal seams. They yield characteristic Crinoidea, 1'rtniitrlte^ Xjtirtferir, 

 litlttitcerata, Bellerophtm, (fonuititet. 



Alternating limestones and red-sandstones, forming a transition group between the carbo- 

 niferous limestone and rcd-sand*tone formations. 



ConKlomerates and sandston<-. No fnviU yet noticed. 



Coloured marls and concretionary limestones, called ' cornstoncs.' A few fossils. 



Tilntones, or flagstone beds. A few fishes. 



PRIMARY STRATA. 



All the fossils belong to extinct species, and often to extinct genem nnd families. They are difiercnt from those in the Secoinlirv timl 

 Tertiary Strata. It has been usual to class the upper systems under the title of Transition Strata, and to confine the name of Primary to the 

 mica-schist and gneiss systems. The following view of the Silurian Strata results from Sir Roderick Murcbison's researches : 



13. Ludlow Rocks 



II. Wenloek Limestone 



15. Caradoc Sandstone 



16. Landetlo Rocks 



t Sandstones. Species of (trhirula, Lingtlla, Tcrcbratula, Spirifera. 

 060 ? Limestone. J'tntamertu, J/vmwitttotni. 

 I Shale. 



,. . i Corals and Crinoidea in vast abundance. 



i-imnhali, I'riHluctn ttrnretaa, Orthoccrata, Calvmtni Ulamnttatkii. and other 

 ( Tril. 



H30 i i . I rnfnmrrttx. Tprpbnittilii, (frtnis t TrilobitP*. 



^ *BiinU> VBnUAIonCK, | 



400 Calcareouit flaggy brd% including AtapKiu liuchii, and other Trilobitc*. 



