WORMS 295 



Echinus glide along the side of the tank on its hundreds of 

 sucking-disks! How beautiful, and at the same time how 

 effective, are the ciliary wheels of the Brachionus. 



I am now going to show you some other examples of 

 travelling machinery in a humble and despised, but far 

 from uninteresting class of animals the Worms. Here is 

 an Earth-worm upon the garden border. With what 

 rapidity it winds along, and now it pokes its sharp nose 

 into the ground, and now it has disappeared 1 If your eye 

 could follow it, you would see that it makes its way through 

 the compact earth not less easily nor less rapidly than it 

 wound along the surface. If you take it into your hand, 

 you perceive no feet, wings, fins, or limbs of any kind; 

 only this long cylinder of soft flesh, divided into numerous 

 successive rings, and tapering to each extremity. The very 

 snout which you saw enter so easily into the substance of 

 the soil is no hard bony point, but formed of the same 

 soft yielding flesh as the other parts. And yet with no 

 other implement does the little worm penetrate whitherso- 

 ever it will through the ground. How does it effect this ? 



The fineness of the point to which the muzzle can be 

 drawn is the first essential. This can be so attenuated 

 that the grains of adherent soil can readily be separated by 

 it when its action is that of the wedge. The body being 

 drawn into the crevice thus made, the particles are sep- 

 arated still further. Now another provision comes in; the 

 whole surface of the skin secretes and throws off a quantity 

 of tenacious mucus or slime, as you will immediately per- 

 ceive if you handle the Worm; this has the double effect 

 of causing the pressed particles of soil to adhere together, 

 and then to form a cylindrical wall, of which they are the 



