XVII. HEREDITY, VARIATION, PLANT AND ANIMAL 



BREEDING 



Problems. --To determine what makes the nff spring of ani- 

 mals or plants tend to be like their parent *. 



To determine what makes the offspring of animals and 

 plants differ from their parents. 



To learn about some methods of plant and aniimtl breeding. 



(a} By selection. 



(6) By hybridizing. 



(c) By other methods. 



To learn about some methods of improving the human race. 



(a} By eugenics. 



(&) By euthenics. 



SUGGESTIONS FOR LABORATORY WORK 



Laboratory exercise. - - On variation and heredity among members of a 

 class in the schoolroom. 



Laboratory exercise. On construction of curve of variation in measure- 

 ments from given plants or animals. 



Laboratory demonstration. - - Stained egg cells (ascaris} to show chromo- 

 somes. 



Laboratory demonstrations. - To illustrate the part played in plant or 

 animal breeding by 



(a) selection. 



(6) hybridizing. 



(c) budding and grafting. 



Laboratory demonstration. - - From charts to illustrate how human char- 

 acteristics may be inherited. 



HEREDITY AND EUGENICS 



Heredity and what it Means. - - As I look over the faces of the 

 boys in my class I notice that each boy seems to be more or less 

 like each other boy in the class ; he has a head, body, arms, and 

 legs, and even in minor ways he resembles each of the other boys 

 in the room. Moreover, if I should ask him I have no doubt 



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