CHAPTER XI. 



WORMS, CRAYFISH, CENTIPEDS, AND OTHER 

 SMALL LAND ANIMALS. 



Earthworms and leeches. — Bring into the schoolroom 

 large live earthworms. The}- may be found in the day- 

 time by digging-, or at night by .searching with a lantern. 

 They often come above ground in the daytime after a 

 heavy rain. They ma)' be kept in flower-pots filled with 

 damp soil, and should be fed bits of raw meat, preferably 

 fat, bits of onion, celery, cabbage, etc. 



h'xamine a live specimen put on a piece of moist paper. 

 Note that the bod)' is made up of rings or segments. 

 Are there an)' legs.'' How does the earthworm move 

 along.' Can )'ou find some short fine bristles, called 

 set;L-, on the bod)-.'' The broad thickened ring or girdle, 

 including several segments near the head, is called the 

 clitcUum. It secretes the cases in which the eggs are 

 laid. Make a drawing of the \\'orm, showing all the 

 e.\'tcrnal features you can make out. 



I'>arthworms live in soft moist soil which is rich in 

 organic matter. Their footl is taken into the mouth 

 mixed with dirt and sand. As this mixture passes 

 through the long alimciitar)' canal the organic particles 

 are taken up and digested. The eggs are laid in a Jiorny 

 capsule which lies in the earth until the )-oung \\'orms 

 emerge. Onl)- a part of the eggs develop in each cap- 

 sule, the rest being eaten by the growing young. Earth- 



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