Earth-Worms in History. 61 



is enlarged, or a fresh one is made close by, so that a larger 

 number of leaves may be drawn in. Generally the interstices 

 between the drawn-in leaves are filled with moist, viscid 

 earth ejected from their bodies, thus rendering them doubly 

 secure. Hundreds of such plugged burrows may be seen 

 during the autumnal and early winter months. 



When leaves, petioles, sticks, etc., cannot be obtained for 

 the mouths of their burrows, heaps of stones, smooth, 

 rounded pebbles, are utilized for protection. When the 

 stones are removed and the surface of the ground is cleared 

 for some inches round the burrow, the worms may be seen 

 with their tails fixed in their burrows dragging the stones 

 inward by the aid of their mouths, stones weighing as much 

 as two ounces often being found in the little heaps, which 

 goes to show how strong these apparently weak creatures 

 are. Work of this kind is usually performed during the night, 

 although objects have been occasionally known to be drawn 

 into the burrows during the day. What advantage worms 

 derive from plugging up the mouths of their burrows, or from 

 piling stones over them, cannot be satisfactorily answered. 

 They do not act in this manner when they eject much earth 

 from their burrows, for then their castings serve to cover the 

 mouth. Perhaps the plugs serve to protect them from the 

 attacks of scolopenders, their most inveterate enemies, or to 

 enable them to remain with safety with their heads close to 

 the mouths of their burrows, which they like so well to do, 

 but which, unless protected, costs many a fellow its life. 

 Besides, may not the plugs check the free ingress of the 

 lowest stratum of air, when chilled by radiation at night, 

 from the surrounding ground and herbage ? The last view 

 of the matter seems especially well taken, because worms 

 kept in pots where there is fire, having no cold air with 

 which to contend, plug up their burrows in a slovenly man- 

 ner, and because they often coat the upper part of their 

 burrows with leaves, apparently to prevent their bodies from 

 coining into contact with the cold, damp earth. But the 



