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Show 28 HABITS OF WORMS. CnAP. I. piano; and their sensitiveness to jars varied much at different times. It has often been said that if the ground is beaten or otherwise made to tremble, worms believe tbat they are pursued by a mole and leave their burrows. From one account that I have received, I have no doubt that they do so when pursued by moles; but a gentleman informs me that he lately saw eight or ten worms leaving their burrows and crawling aLout the grass on some boggy land on which two men had just tra1npled while setting a trap; and this occurred in a part of Ireland where there were no moles. I beat the ground in many places where worms abounded, but not one emerged. When, however, the ground is dug with a fork and is violently disturbed beneath a worm, it will often crawl quickly out of its burrow. The whole body of a worm is sensitive to contact. A slight puff of air from the mouth causes an instant retreat. The glass plates placed over the pots did not fit closely, and blowing through the very narrow chinks thus left, often sufficed to cause a rapid retreat. They sometimes perceived the eddies in the ' CHAP. I. THEIR SENSES. 29 air caused by quickly removing the glass plates. 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 organ of touch; and there is some reason to believe, as we shall see in the next chapter, that they are thus enabled to gain a general notion of the form of an o~joct. Of all their senses that of touch, including in this term the perception of a vibration, seems much the most highly developed. In worms the sense of smell apparently is confined to tho perception of certain odours, and is feeble. They were quite indifferent to my breath, as long as I breathed on them very gently. This was tried, because it appeared possible that they might thus be warned of the approach of an enemy. They exhibited the same indifference to my breath whilst I chewed some tobacco, and while a pellet of cotton-wool with a few drops of millefleurs perfume or of acetic acid was kept in my mouth. Pellets of cotton-wool soaked in ~obacco juice, and in mille:fleurs perfume, and In paraffin, were held with pincers and were |