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Updated: June 28, 2025
Uncites Gryphus, Def. Middle Devonian. With the above are found no less than eleven genera of stone-lilies or crinoids, some of them, such as Cupressocrinites, distinct from any Carboniferous forms. The mollusks, also, are no less characteristic; of 68 species of Brachiopoda, ten only are common to the Carboniferous Limestone.
In this period corals were wonderfully abundant, particularly in the great internal sea which spread over what is now known as the Mississippi Valley. Everywhere over this region must have grown in the shallow water great numbers of creatures called crinoids or stone lilies. They were attached to the bottom by slender stems, sometimes many feet long.
There are also impressions of the bark and fruit of trees, together with shells, crinoids, corals, remains of fishes and flying lizards, and some few trilobites, crablike animals with a shell somewhat like the back of a lobster, but marked into three divisions or lobes, from which its name comes.
They prove that the mollusks and crinoids held to be characteristic of early Silurian strata, and supposed to have become extinct long before the mollusks and crinoids of the later Silurian strata came into existence, were really flourishing at the same time with these last; and that these last possibly date back to as early a period as the first.
I could see, without great effort of the imagination, the shoal of Lockport teeming with the many genera of crinoids which the geologists of New York have rescued from that prolific Silurian deposit, or recall the formations of my native country, in the hill-sides of which also, among fossils indicating shoal water deposits, other crinoids abound, resembling still more closely those we find in these waters.
In its most calcareous form the Mountain Limestone is destitute of land- plants, and is loaded with marine remains the greater part, indeed, of the rock being made up bodily of crinoids, corals, and bryozoa with interspersed mollusca. Palaeozoic type of lamelliferous cup-shaped Coral. Order ZOANTHARIA RUGOSA, Milne Edwards and Jules Haime. a.
He would bring out a piece of rock and examine it, and say to himself, "It is limestone it has crinoids and corals in it the rock is right" Then he would throw it down with a sigh, and say, "But that is nothing; where coal is, limestone with these fossils in it is pretty certain to lie against its foot casing; but it does not necessarily follow that where this peculiar rock is coal must lie above it or beyond it; this sign is not sufficient."
In the Silurian ages, invertebrates brachiopods and crinoids and cephalopods were the dominant types. But very early no one knows just when there came fishes of many strange forms, some of the early ones enclosed in turtle-like shells.
Below this Devonian limestone, its crystals sparkling in the sunshine, with its coral fossils, its fragments of crinoids, and its broken shells of brachiopods, down through the Devonian, the Silurian, the Ordovician, and the Cambrian rocks, down to the original crust formed when first the earth began to cool, if any there be remaining; all these miles of rocks are inorganic, built up of crystals.
At the latter, the first cast of the large dredge was made on a ledge of shoals in a depth of eighty fathoms, and, among countless other things, a number of stemmed crinoids and comatulae were brought up. An ardent student of the early fossil echinoderms, it was a great pleasure to Agassiz to gather their fresh and living representatives.
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