IN THE FIELD 191 



/. It is used in the manufacture of starch. Ask a 

 farmer's wife how you can make starch from potatoes. Put 

 a drop of potato juice on dark paper, and examine it with a 

 good lens ; you will see many of the starch grains. What 

 becomes of the starch in the tuber which is planted ? Ex- 

 amine such a tuber. 



3. Diseases and insect enemies. The tubers in the ground 

 and the foliage above the ground are subject to several dis- 

 eases, caused by microscopic organism. About these diseases 

 consult your state reports. Its most formidable insect en- 

 emy, the potato beetle, will form the subject of one of our 

 future lessons. On what could the potato bugs live, before 

 potatoes were planted in this country ? 



4. Remarks. The potato crop is never a complete fail- 

 ure. Since potatoes have been generally cultivated, no 

 general famine has occurred in western Europe. In former 

 centuries great famines were quite common. In India and 

 in China they are still common, and a few years ago even 

 Russia experienced a serious famine. Why should a failure 

 of crops cause a famine in Russia, when it does not have 

 that result in England, France, or Germany ? 



27. Concluding Remarks on Cultivated Plants. 



MATERIAL : Show as many of the plants mentioned below as you 

 can procure. Also show the products made from them, if practicable. 



The cultivated plants which we have just studied by no 

 means complete the list of those grown in this region. In 

 our fields we also find flax, timothy, clover, millet, and 

 perhaps the sugar beet. Among the corn we observe the 

 long vine and large fruit of the pumpkin. One of our 

 farmers who keeps bees has sown several acres of buckwheat, 

 and how busy the bees are in that field ! Some farmers cul- 

 tivate small fields of beans, peas, and onions, and in warm, 

 sheltered places the boys and girls have their melon patches. 



