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In some marbles there are so many that the stone seems to be almost made of them. When a slab is cut and polished, the fossils are of course cut into; but even then we can sometimes see their shape. One of the most common is the crinoid. This was really an animal, but it looked somewhat like a closed pond lily with a long stem, and people used to call it the stone lily.
But then, on careful consideration of the facts, the objection arises that the stalk, calyx, and arms of the paleozoic Crinoid are exceedingly different from the corresponding organs of a larval 'Comatula'; and it might with perfect justice be argued that 'Actinocrinus' and 'Eucalyptocrinus', for example, depart to the full as widely, in one direction, from the stalked embryo of 'Comatula', as 'Comatula' itself does in the other.
But then, on careful consideration of the facts, the objection arises that the stalk, calyx, and arms of the paleozoic Crinoid are exceedingly different from the corresponding organs of a larval 'Comatula'; and it might with perfect justice be argued that 'Actinocrinus' and 'Eucalyptocrinus', for example, depart to the full as widely, in one direction, from the stalked embryo of 'Comatula', as 'Comatula' itself does in the other.
Coleridge says about the primary art of writing: "First, there is mere gesticulation, then rosaries, or wampum, then picture language, then hieroglyphics, and finally alphabetic letters," the last an evolution from all that went before. But there is no more suggestion of an alphabet in the sign language of the North American Indian than there is of man in a crinoid.
Let us give a glance now at the animals which inhabited the waters of this period. In the Radiates we shall not find great changes; the three classes are continued, though with new representatives, and the Polyp Corals are increasing, while the Acalephian Corals, the Kugosa and Tabulata, are diminishing. The adjoining wood-cut represents a characteristic Crinoid of the Carboniferous age.
Animal forms were abundant; many of them were new to science; and among them was one of surpassing interest, the small crinoid, of which you have a specimen, and which we at once recognised as a degraded type of the Apiocrinidoe, an order hitherto regarded as extinct, which attained its maximum in the Pear Encrinites of the Jurassic period, and whose latest representative hitherto known was the Bourguettocrinus of the chalk.
ECHINODERMS. The cystoid reaches its climax, but there appear now two higher types of echinoderms, the crinoid and the starfish. The CRINOID, named from its resemblance to the lily, is like the cystoid in many respects, but has a longer stem and supports a crown of plumose arms. Stirring the water with these arms, it creates currents by which particles of food are wafted to its mouth.
How like to a many-rayed starfish is our creeping crinoid! Few of us, unless we had studies about these creatures, could distinguish between a crinoid and one of the frisky little dancing stars, or serpent stars, which are so common in the rocky caves along our coast. This relationship is no less real than apparent.
Enough to occupy half a dozen competent zoologists for a whole year, if the specimens could be kept fresh for that length of time. The first haul brought up a Chemidium-like sponge; the next gave us a crinoid, very much like the Rhizocrinus lofotensis, but probably different; the third, a living Pleurotomaria; the fourth, a new genus of Spatangoids, etc., etc., not to speak of the small fry.
They are placed upon table 24, near a cast of a stem and flower, that has the appearance of a fossil plant, but is in reality a cast of a crinoid star-fish that once existed in great abundance.
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