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Show 116 JIA 13ITS OF WORMS. CnAP. II. a wen as the eeds, arc carried down from the surface by being swallowed ; for a surpri~ ino· number of glass beads, bits of tile and of glass were certainly thus carried down by worms kept in pots; but some may have b en carried down within their mouths. The sole conjecture which I can form why worms line their winter-quarters with little stones and seeds, is to prevent tlteir closely coiled-up bodies from coming into close contact with the surrounding cold soil; and such contact would perhaps interfere with their respiration which is effected by the skin alone. A worm after swallowing earth, whether for 1naking its burrow or for food, soon comes to the surface to empty its body. The ejected earth is thoroughly mingled with the intestinal secretions, and is thus rendered viscid. After being dried it sets hard. I have watched worms during the act of ejection, and when ~.he earth was in a very liquid state it was ~jected in little spurts, aud when not s.o liquid by a slow peristaltic movement. It. Is not cast indifferently on auy side, but w1th some care, first on one and then on another side; the tail being used ahnost like a trowel. I CuAP. H. EJECTION OF 'L'IIEIR CASTINGS. 117 As soon as a little lteap i formeJ, the worm apparently a voids, for the sake of afety, protruding its tail; and tbe earthy matter is forced up through the prcviou ly deposited soft mass. The mouth of the same burrow is u:secl for this purpose for a considerable time. In the case of the tower-like castings ( ee Fi 0'. 2) ncar Nice, and of the similar but still taller towers fi·om Bengal (hereafter to be described and figured) a considerable degree of skill is exhibited in their construction. Dr. King also observed that the passage up thet1e towers hardly ever ran in the same exact line with the underlying burrow, so that a thin cylindrical object such as a haulm of grass, conld not be passed down the tower into the burrow; and this change of direction probably serves in some manner as a protection. When a worm comes to the surf~we to eject earth, the tail protrudes, but when it collects leaves its head must protrude. Worms therefore must have the power of turning round in their clo elyfitting burrows; and this, as it appears to us, would be a difficult feat. Worms do not always eject their castings on |