20. HOW TO IMPROVE PLANTS. 



Illustrative material: Show a number of individual plants of 

 the same kind, or of branches from as many plants, and require 

 the pupils to search out the differences shown by the same part 

 in different specimens. Show also a number of ears of Indian 

 corn of different forms and let each pupil pick out the best ear 

 according to his own ideal. Always require the reasons for 

 the choice. 



Plants Not Alike. If we go out into a field of ripe 

 Indian corn and try to find two corn plants that are alike 

 in all respects, we shall fail. One will be a little taller 

 than the other; one will have a thicker stalk than the 

 other ; or one will have a longer ear than the other. If we 

 try to pick out from a pile of husked corn two ears that 

 are just alike, we shall fail'again. One ear will be thicker, 

 or longer, or will have smaller kernels, than the other. 

 We shall even find it hard to select two kernels from the 

 same ear that are just alike. Two plants rarely, if ever, 

 groin just alike. 



Select Seeds with a Purpose. Although two plants 

 rarely grow alike, the plants that grow from the seed of 

 a parent plant are usually more nearly like the parent than 

 they are like any other plant. For example, if one pea 

 plant in a row bears longer and more slender pods than 

 any other, the plants grown from the seeds in these long 

 and slender pods are likely to produce long and slender 

 pods also. Some of them will probably be a little longer 

 and more slender than any of the parent pods. If we 



88 



