A number of years ago I took a number of walking trips over that section of New York state known as the Catskill Mountain region. The start was made at the mouth of Catskill Creek, which was followed up into the mountains until we came to a peculiar light, slate-colored rock. This rock, where the stream had washed the earth away, was dotted with little disks (Fig. 44), which being harder than the rock itself had been weathering, and stood out in high relief. A mile or two from the river the rocks were covered with these disks, in fact, seemed to be made up of them. Some were large, some small, as if millions of pipestems had been cut into sections and scattered about.

These disks told an interesting story. We read by them that ages ago the region now covered by farms and summer resorts was the bottom of a shallow, tropical sea. We could go further and describe even the appearance of the bottom of that sea, and what grew and lived there. Scattered about on the rock were myriads of shells, corals, teeth, fish bones, and a variety of objects, all the remains of animals which once lived in this ancient ocean.

We find that the little disks fit together, and collecting them, pile them up, forming a stem a foot or more long. Among them we find one which is attached to a rootlike object, and this is placed at the bottom. Near by we find a flowerlike or budlike form (Fig 45), which may well serve as the flower of this stem, and so we add it and produce a striking resemblance to the crinoid shown in Figure 46. This is an interesting and beautiful animal which was one of the commonest forms of the ancient seas. It grew in groves and masses, as we may see by the vast numbers strewn in the old ocean bed; and when they died, they were scattered here and there and hardened into the old bed.

The crinoids resemble lilies so closely that they are called stone lilies. They are animals, however, related to the starfishes. They have a long stem, with rootlike branches to support it, and are capped with what appears like an inverted starfish, and is literally a starfish perched upon a stem. Fossil crinoids have long been known, and beautiful specimens may be seen in all our museums, but the fact that they still live upon the globe is a modern discovery. It is said that Agassiz stated that he expected to find them alive off the coast of Cuba, and when a deep locality was dredged, up came the living crinoids, or forms almost identical with them. Since then they have been dredged in great numbers by all the great deep-sea explorers. Some have long stems, some short. On one, the Comatula, when it is full grown, the crinoid leaves its stalk, and lives a free, roving life after the fashion of many starfishes.

The crinoid, with its long slender stem, its branching tendrils, its flowerlike top, is one of the most graceful of all animals, as might be imagined from the drawing. Examine the crinoid as closely as one may, it still resembles a stone lily, and only its slow movements, contracting and folding, suggest life. Nevertheless, it is a very complicated animal. It consists of a central body, protected by numerous plates, as seen in Figure 46. From the edges extend five, or often more, branches or arms, and from them in turn branch other arms, so that the top resembles a feather or brush, from which they are called feather stars. In the center of the stars is a mouth, food being caught by the many branching tentacles. The history of the development of crinoids is very interesting. They pass through several curious stages in the course of growth from infancy to old age, and some of the shapes are so curious that no one, not familiar with them, would suspect that here was a growing crinoid.