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Page:Popular Science Monthly Volume 13.djvu/326

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312
THE POPULAR SCIENCE MONTHLY.

SEA-SIDE STUDIES.

By Professor SANBORN TENNEY.

AMONG the thousands who visit the sea-shore in summer, there are many who, although not naturalists, are more or less interested in the various marine forms which there abound, and perhaps a brief notice of some of these forms will be acceptable to those who have not made a special study of life as it is revealed in the sea.

If an observer be on a rocky shore he will not fail to become interested in the "sea-anemones," those "flowers of the sea" which at first view appear to be on the border-land between plants and animals, so that one hardly knows whether to refer them to the vegetable or to the animal kingdom.

Fig. 1.—Actinia, or Sea-Anemone (Metridium marginatum, Milne-Edwards): c, closed; o, opening; e, expanded.

Although some sea-anemones live in the sand (Fig. 2), the home of the ordinary kinds is the pools and caverns among the rocks; here we may find and study them when the tide is out. Groups, sometimes in thousands, and standing so closely together that they cover the whole interior of the rocky cavern or grotto, are not uncommon. Some are expanded to their fullest extent, like a full-blown flower; others are only partly open; others are just opening; and others still are closed as tightly as the bud of a flower, which they more or less resemble.

Various are the colors which they exhibit, from pale or nearly white to the richest hues of pink, rose, red, and purple.

In the centre of the top there is an opening or mouth, which leads directly into a central sac or stomach, and around the mouth are rows of long and delicate hollow appendages, which the animal moves freely