Another reparation or renewal by the octopods of worn or injured portions of their limbs is the frequent shedding of the outer skins of their suckers, the epidermis of the flat surface of them, by which they adhere, and travel from place to place. These cast-off skins may generally be seen floating in the water in their tanks in the form of very thin, filmy discs, with a hole in the centre. Seeking a reason for this, it appears to me that these, their feet-coverings, become worn by crawling and climbing over the rough rocks, and that it is a provision of nature for the renewal of the holding surface of their suckers, necessary for the production of a sufficient vacuum, and the very best method by which the repairs of the soles of their boots can be “neatly executed.” And, as their feet increase in size with their general growth, it may also be that they outgrow their shoes as quickly as children do theirs, and that, therefore, they cast them periodically when they require larger ones, as the barnacles do their plumes, the crustacea their shells, and snakes their skins. Sometimes the whole shoe is thrown off; at others only the sole. When the octopus desires to get rid of this worn skin it curls its arms together close to its body in a peculiar manner, and rubs them one against another with a rapid motion of coiling and uncoiling which suggests the action of “Sir Jacob,” the father of Thomas Hood’s “Miss Kilmansegg,” when he “In the fulness of joy and hope, Seemed washing his hands with invisible soap In imperceptible water.” It appears to delight in thus cleaning itself and giving itself a good rubbing and scrubbing all over, as a strong man enjoys his “matutinal tub” and a hearty rub with a rough towel afterwards; or as a bird, with evident pleasure, preens its feathers, and bathes in water or sand. This cleansing process has been erroneously supposed to indicate sexual excitement. CHAPTER VII. SPAWNING OF THE OCTOPUS.