Earth- Worms in History. 67 



be not mere excavations, but may be compared with tunnels 

 lined with cement. Those which run far down into the 

 ground generally, or at least frequently, terminate in little 

 chambers, where one or several worms pass the winter rolled 

 up into a ball. Small pebbles and seeds as large as grains 

 of mustard are carried down from the surface by being swal- 

 lowed or within the mouths of worms, as well as bits of glass 

 and tile, whose only use in their winter-quarters seems to be 

 the prevention of their closely coiled-up bodies from coming 

 into contiguity with the surrounding cold soil, for such con- 

 tact would perhaps interfere with their respiration, which is 

 effected by the skin alone. 



After swallowing earth, whether for making its burrow or 

 for food, the earth-worm soon comes to the surface to empty 

 its body. The rejected matter is thoroughly mixed with the 

 intestinal secretions, and is thus rendered viscid. After be- 

 coming dried, it sets hard. When in a very liquid state the 

 earth is thrown out in little spurts, and when not so liquid 

 by a slow peristaltic movement of the intestine. It is not 

 cast indifferently on any side, but first on one and then 

 on another, the tail being used almost like a trowel. The 

 little heap being formed the worm seemingly avoids, for the 

 sake of safety, the use of its tail, the earthy matter being 

 forced up through the previously deposited soft mass. The 

 mouth of the same burrow is used for this purpose for a 

 considerable time. When a worm comes to the surface to 

 eject earth, the tail protrudes, but when it collects leaves its 

 head must protrude, and thus worms must have the power 

 of performing the difficult feat, as it seems to us, of turning 

 round in their closely-fitting burrows. Worms do not always 

 eject their castings upon the surface of the ground, for when 

 burrowing in newly turned-up earth, or between the stems 

 of banked-up plants, they deposit their castings in such 

 places, and even hollows beneath large stems lying on the 

 surface of the ground are filled up with their ejections. Old 

 burrows collapse in time. The fine earth voided by worms, 



