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Investigation fails to locate in worms any organ of hearing, from which must be concluded that they are insensible to sounds. The shrill notes of a metallic whistle sounded near them, and the deepest and loudest tones of a bassoon, failed to awaken the least notice. Although indifferent to modulations in the air, audible to human ears, yet they are extremely sensitive to vibrations in any solid object. Even the light and delicate tread of a robin affrights and sends them deep into their burrows. It has been said that if the ground is beaten, or otherwise made to tremble, that worms believe they are pursued by a mole and leave their burrows, but this does not stand the test of experiment, for the writer has frequently beaten the ground in many places where these creatures abounded, but not one emerged. A worm’s entire body is sensitive to contact, the slightest puff of air from the mouth causing an instant retreat. When a worm first comes out of its burrow it generally moves the much-extended anterior extremity of its body from side to side in all directions, apparently as an object of touch, and there is good reason to believe that they are thus enabled to gain a general knowledge of the form of an object. Touch, including in this term the perception of a vibration, seems much the most highly developed of all their senses. The sense of smell is quite feeble, and is apparently confined to the perception of certain odors. They are quite indifferent to the human breath, even when tainted by tobacco, or to a pellet of cotton-wool with a few drops of Millefleur’s perfume when held by pincers and moved about within a few inches of them. The perception of such an unnatural odor would be of no service to them. Now, as such timid creatures would almost certainly exhibit some signs of any new impression, we may reasonably conclude that they did not perceive these odors. But when cabbage leaves and pieces of onion were employed, both of which are devoured with much relish by worms, the result was different. These, with bits of fresh raw meat, have been buried in pots beneath one-fourth of an inch of common garden soil, or sometimes laid on pieces of tin foil in the earth, the ground being pressed down slightly, so as not to prevent the emission of any odor, and yet they were always discovered by the worms that were placed in the pots, and removed after varying periods of time. These facts indicate that worms possess some power of smell, and that they discover by this means odoriferous and much-coveted kinds of food.