Page:Natural History, Mollusca.djvu/148

136 into segments, cut, and cut again, make fine bushy tufts in a deep pool, and every segment of every frond reflects a flush of the most lustrous azure, like that of a tempered sword-blade.

I have said that animals of various kinds inhabit these rock-pools. They are cavities of irregular shapes and diverse dimensions in the surface of the rock, covered by the sea at every incoming tide, and left full when it recedes. The water, therefore, presently becomes as clear as crystal, and the surface being too small to be ruffled by ordinary breezes, the eye can easily penetrate even to the bottom, and mark all that is going on within. There are little fishes, with bright eyes and silvery sides, peeping from under the shelter of the broad leaves, or darting out with vibrating fins from beneath one projection of the rock to another. Elegantly painted prawns are swimming leisurely to and fro, and hundreds of other smaller Crustacea are playing about. Sea anemones of different species stud the rocky sides, and attract the eye with their brilliant colours—crimson, purple, scarlet, green, and white—resembling gorgeous flowers, or ripe and mellow fruits, according as they are expanded or contracted. The shelled Gasteropods are not wanting; the little Cowry, the Purpura, the various species of Trochus, to say nothing of limpets and periwinkles. And here we may often see the lovely Nudibranchs and Tectibranchs, crawling with graceful elegance about the fronds of the waving Algæ, or floating at the surface of the still water in that reversed position already described.

Many more objects of like kind the observant naturalist will find from time to time, to gratify his