Page:The aquarium - an unveiling of the wonders of the deep sea.djvu/224

Rh to know what is the use of the slender first pair, which are also furnished with didactyle hands, but very diminutive and feeble. See the Prawn, however, washing himself after dinner, or at any other spare moment, for he is careful to maintain his polished coat of mail most scrupulously clean. You will then see that the front feet are cleansing organs. They are beset with hairs which stand out at right angles to the length of the limb, radiating in all directions, like the bristles of a bottle-brush. You will not see them to advantage, it is true, in dried specimens; but in a living state, or even when preserved in spirits, they are conspicuous enough under a lens. These are the Prawn's washing brushes, especially applied to the cleansing of the under surface of the thorax and abdomen. When engaged in this operation, the animal commonly throws in the tail under the body, in that manner which we see assumed in the pink specimens that are brought to table, which is not, however, the ordinary posture of life, the body being nearly straight. Then he brings his forefeet to bear on the belly, thrusting the bottle-brushes to and fro, and into every angle and hollow with zealous industry, withdrawing them now and then, and clearing them of dirt by passing them between the foot-jaws. The reason of the inbending of the tail is manifest; the brushes could not else reach the hinder joints of the body, and still less the swimming plates; but by this means every part is brought within easy reach. Sometimes the brushes are inserted between the edge of the carapace and the body, and are thrust to and fro, penetrating to an astonishing distance, as may be