CHAPTER XIII.
NEWER PLIOCENE STRATA AND CAVERN DEPOSITS.
Chronological classification of Pleistocene formations, why difficult--Freshwater deposits in valley of Thames--In Norfolk cliffs--In Patagonia--Comparative longevity of species in the mammalia and testacea--Fluvio-marine crag of Norwich--Newer Pliocene strata of Sicily--Limestone of great thickness and elevation--Alternation of marine and volcanic formations--Proofs of slow accumulation--Great geographical changes in Sicily since the living fauna and flora began to exist--Osseous breccias and cavern deposits--Sicily--Kirkdale--Origin of stalactite--Australian cave-breccias--Geographical relationship of the provinces of living vertebrata and those of the fossil species of the Pliocene periods--Extinct struthious birds of New Zealand--Teeth of fossil quadrupeds 146