| | o | Urgonian (Barremian)--Atherfield clay; | some Niobrara marls and | | | u | massive Hippurite limestones of | limestones are likewise of | | | s | southern France. | marine origin, but the lower | | | . | Neocomian--Weald clay and Hastings sand; | members of the series (Benton | | | | Hauterivian and Valanginian sub-stages | and Dakota) show another great | | | | of Switzerland and France. | representation of fresh-water | | M | | | sedimentation with lignites and| | e | | | coals. | | s | | | In California a vast succession | | o | | | of marine deposits (Shasta- | | z | | | Chico) represents the | | o | | | Cretaceous system; and in | | i | | | western British N. America | | c | | | coal-seams also occur. | | +---+-------------------------------------------+----------------------------------+ | o | | Purbeckian--Purbeck beds; Munder Mergel; | Representatives of the Middle and| | r | | largely present in Westphalia. | lower Jurassic formations have | | | | Portlandian--Portland group of England, | been found in California and | | S | | represented in S. France by the thick | Oregon, and farther north among| | e | | Tithonian limestones. | the Arctic islands. | | c | | Kimmeridgian--Kimmeridge Clay of England; | Strata containing Lower Jurassic | | o | | Virgulian and Pterocerian groups of N. | marine fossils appear in | | n | J | France; represented by thick limestones | Wyoming and Dakota; and above | | d | u | in the Mediterranean basin. | them come the _Atlantosaurus_ | | a | r | Corallian--Coral Rag, Coralline Oolite; | and _Baptanodon_ beds, which | | r | a | Sequanian stages of the Continent, | have yielded so large a | | y | s | comprising the sub-stages of Astartian | variety of deinosaurs and other| | . | s | and Rauracian. | vertebrates, and especially the| | | i | Oxfordian--Oxford Clay; Axgovian and | remains of a number of genera | | | c | Neuvizyan stages. | of small mammals. | | | . | Callovian--Kellaways Rock, Divesian | | | | | sub-stage of N. France. | |