4 8 



THE WORMS. 



shrubs and trees. According to the same authority, during the Sikh 

 rebellion an entire English regiment was forced to retreat before the 



myriads of blood- 

 suckers. 



VALUE. Leeches, 

 from their extreme 

 sensitiveness to at- 

 mospheric' changes, 

 are sometimes used 

 as barometers, but 

 their principal value 

 is in medicine. In 

 one .year 7,000,000 

 were used in London, 

 at $10 per 1,000. 



Earth-'Wonns. The earth or angle-worms (Fig. 51) 

 are cylindrical, and composed of numerous joints or seg- 

 ments, each divided by a thin muscular partition. Upon 

 examination, the lower portion of the segments will be 



FlG. 50. Land-leeches of India, racing to attack 

 some animal. 



FlG. 51. Earth-worm (Lutnbn'cus terrestris}. 



found perforated with four rows of minute holes, through 

 which extend bristles that are really the feet. These curve 

 backward, and, by extending the head and throwing them 

 out, the remainder of the body is pulled along, a fresh 

 hold taken, and so on. They multiply by eggs that are 

 protected by capsules, those of some kinds containing 

 fifty eggs. 



VALUE. Eaten by the Indians, and valuable as preparing the 

 earth for the reception of seeds.* 



* The amount of vegetable mold thus brought to the surface in a 

 single year by worms amounts, according to Darwin, in some places to 

 ten tons in a single acre ; they rarely go below six feet, and it has 



