CHAPTER VII.. Classification of the Naturalist Not Always Correspondent With

Classification of the naturalist not always correspondent with the order of nature--Incongruous grouping of animals in the invertebrate division--Rudimentary skeleton of the cephalopods--Introduction of the vertebrate type into creation--Ichthyolites of the carboniferous rocks--Their state of keeping--Classification of fossil fishes--Placoids--Ichthyodorulites--Ganoids--Their structure exemplified in the megalichthys and holoptychius--Cranium of megalichthys--Its armature of scales--Microscopic structure of a scale--Skeleton of megalichthys--History of the discovery of the holoptychius--Confounded with megalichthys--External ornament of holoptychius--Its jaws and teeth--Microscopic structure of the teeth--Paucity of terrestrial fauna in coal measures--Insect remains--Relics of reptiles--Concluding summary of the characters of the Carboniferous fauna--Results,

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