Page:The American Cyclopædia (1879) Volume XII.djvu/829

Rh PALAEONTOLOGY 815 TABULAE ARRANGEMENT OF THE GEOLOGICAL FORMATIONS (continued).

Permian. Upper Permian. Middle Permian, or Magnesian h'mestone. Lower Permian. Sometimes .regarded as a group of passage beds from the coal measures to thetnassic. MoUuscan fauna not abundant. Brachiopoda, some of which are common to the carboniferous. Last appearance of the genus pro- duct Bryozoa abundant. Fossil fishes mostly of genera Smmooto the carboniferous. The flora is mainly peculiar to tbl group buf^some species are common to this and the coal measures. Coal measures and upper limestones. Upper carboniferous lime- stones and shales. Upper and low'r coal measures Conglomerate. Bed shales, &c., at base. Bryozoa and brachiopoda abundant, lamellibranchiata common ; some corals, echmideae crinoidea, cephalopoda. First appearance of batrachian reptiles and air-breathing mollusca, insects, scorpions, and shrimp-like crustaceans ; and last appearance of trilobites. Ganoid fishes numerous. Land plants, as tree ferns, sigillaria, stigmaria, catamites, &c. CABBONIFEKOt Lower carboniferous lime- stones. Chester or Kaskaskia lime- stone. St. Louis h'mestone. Warsaw h'mestone. Keokuk limestone. Burlington limestone. C ^o * abu ? dant - *ry zoa abundant in the upper members. Brachi- opoda abundant. Mollusca common throughout. Crinoidea extremely abundant. Echmoidea and blastoidea very abundant, the latter more common m the upper members, which contain fewer crinoidea. Cestra- ciont fishes abundant. (Formation calcareous.) Waverley group. Conglomerates. Sandstones, shales, and lime- stones in thin beds. Brachiopoda and lamellibranchiata, bryozoa, crinoidea. Fish remains. J? ossil ferns. Marine plants of the genus dicfyophyton. Land plants of the genera sigillaria, lepidodendron, calamites, &c. Catskill group. Conglomerates. Sandstones. Ked, green, and olive shales and sandstones. Remains of ganoid fishes (holoptycMus) abundant, with fucoids and many land plants, as ferns, &c. Cfomung group. Sandstones, shales, and con- glomerate. Limestone in the west. Fucoids and land plants. Lamellibranchiate shells and brachiopods abun- dant. Gasteropods, cephalopods, and crustaceans rare. Crinoidea and bryozoa not common. Eemains of cestraeiont fishes. In the calcareous beds of the western extension are many corals, stromatopora, brachio- pods, &c. 1 VONIAN. Portage group. Shales and sandstones. Fucoids and land plants ; crinoidea. Lamellibranchiata and brachiopoda rare. Cephalopoda (goniatites) common. Fish remains of remarkable forms, belonging to the genera dinichtJvys, aspidichthys, ctenacanthus, &c. a 5 Hamilton group. Shales, calcareous shales, lime- stones, &c. Fucoids (epirophyton) and land plants abundant in certain beds. LameHi- branchiata and brachiopoda abundant. Gasteropoda and cephalopoda common. Crustacea, crinoidea, and corals abundant. Upper Helderberg group. Corniferous and Onondaga limestones. Schoharie grit. Corals, bryozoa, and brachiopoda abundant. Gasteropoda and lamelli- branchiata common. Among the cephalopoda the genus goniatites is first noticed. Crustacea (trilobites of extravagant forms) common. Teeth, body plates, and spines of fishes, mostly cestracionts, appear for the first time, some of them of very ponderous dimensions. Macro- petalichthys, onychodus, &c. Land plants make their first appearance, with the exception of upper Silurian (?) in Nova Scotia. Caudagalli grit. Fossils extremely rare. Some marine plants (spirophyton). Oriskany sandstone. Brachiopoda abundant and of remarkable forms. Gasteropoda abundant. Lamellibranchiata and crinoidea few. 8ILTTBIAN. Lower Helderberg group. Upper pentamerus h'mestone. Shaly limestone. Pentamerus limestone. Tentaculite limestone. Corals and bryozoa. Brachiopoda and gasteropoda abundant. Crinoidea, cystidea, and Crustacea common. Lamellibranchiata and cephalopoda few. Petrospongia, &c. M w Waterlune. Crustacea of the genera eurypterus, pterygotus, ceratiocarit, &c. E p Onondaga or Salina forma- tion. Magnesian and argillaceous limestones. Bed, gray, and greenish marls. The formation essentially non-fossiliferous. 1 Niagara group. Limestones. Shales. Sponges, corals, bryozoa, crinoidea, brachiopoda, and Crustacea abundant. Cephalopoda common. Lamellibranchiata and gasteropoda few. MIDDLE SI Clinton group. Shales, sandstones. Limestones, iron ore. Medina sandstone. Marine plants abundant. Bryozoa, graptolites, brachiopoda, a few lamelli- branchiata, gasteropoda, cephalopoda, Crustacea, and crinoidea. 6 29 Anticosti group, island of An- ticosti, representing the Clin- ton and Medina groups. YOL. XII. 52 Highly fossiliferous in brachiopoda and mollusca, with bryozoa, corals, and Crustacea.