Page:The fairy tales of science.djvu/151

Rh fishes in with his outer foot-jaws. Each of these jaws is like a sickle, composed of five joints beset with parallel bristles. When the jaw is straightened, the bristles stand apart and let the water flow freely between them; when the joints are bent to a curve, the bristles overlap and form a net or hair spoon. This net is the more perfect because each bristle itself is feathered with two rows of hair. After a haul, the little fisherman picks what he likes to eat out of his net, and casts again. He throws his net out, with the claws extended, and the meshes consequently open, so that all rejected particles are washed away; then he again makes for himself a spoon wherewith to pick up victuals.

In addition to his nippers this crab has four pairs of legs; but only three pairs are at first sight visible. The fourth is a very tiny pair, folded down in a groove beneath the edges of the shell. Each of these little legs has at the end a pair of fingers and a little brush of hairs. With the two brushes it scrubs and cleanses its whole body, and with the two pairs of fingers—each being more properly comparable to a finger and thumb—it picks off any dirt that cannot be removed by brushing.

But who is that long-legged little gentleman with the crusty and prickly body? He is another member of the prolific crab family, and is perhaps one of the most valuable servants in the mermaid's