60 The Earthworm. 



is no distinct head, but the mouth is at this end. Here, 

 too, are the largest rings. The. other end, or tail (Fig. 

 1. I 2), consists of smaller rings, and is flattened at the tip 

 (Fig. 1, w). About one third of the distance from the 

 head to the tail is the saddle (Fig. 1, n), where the rings 

 are thickened and show much less plainly. 



We can coant the rings on an aloobolic Bpeoimen, bnt ve muat 

 remember that the aarface o{ each ring is divided by a skin fold, 

 su that there are only half as many rings as folds. Extending in- 

 ward to the intestine are mnacnlar partitions vhioh separate the 

 rings and divide the body into a series of chambers. 



In color the worm is reddish brown, the upper side 

 being much darker than the lower. At first we think it 

 has no skeleton, but if we put an alcoholic specimen in 

 water for a few hours, we can remove a thin, horny- 

 cuticle, or outer layer of the skin. Sometimes we detect 

 a beautiful iridescence, caused by the play of light on the 

 tiny folds of the cuticle. 



Now, taking the head end of the worm gently between 

 the fingers, and holding it up, we shall see it open its 

 mouth in its efforts to escape, and thrust' out a large, 

 white, membranous pouch, into which the mouth leads. 

 This pouch is drawn forward when the worm is digging 

 its burrow, thus swelling out the head and making a much 

 larger opening in the soil. As we hold the worm, we 

 feel the pressure of the stiff hairs, or bristles, on its 

 sides, which we see as bright points when it draws up its 

 rings and pushes against our fingers. There are two 

 double rows of these hook-like bristles (Fig. 1, s) on each 

 side of the body, just where the darker color of the back 

 joins the lighter color of the under side. 



Earthworms have no teeth, bat with their lips they pinch off the 

 soft parts of decaying leaves, on which they feed. The red thread 

 along the worm's back is the principal blood-vessel. The dark 

 tabe passing throngh the body is the intestine, which contains earth, 

 swallowed partly to get it oat of the barrow, and partly for the de- 

 caying plants in it. 



