EXERCISE 144 



Problem. How near alike are the individuals or the corresponding organs of individuals of the 

 same kind ? 



What to use. A hundred or more persons, flowers, leaves, hands', plants, or other convenient indi- 

 viduals or organs of the same kind ; a ruler divided into millimeters or into tenths of an inch, or some 

 other suitable measuring instrument for example, a dynamometer. 



What to do. Count the stamens of a hundred buttercups, the ray flowers of a hundred daisies or 

 asters, or the ribs on a hundred elm or beech leaves ; or measure the lengths of a hundred beans, 

 corn grains, eggs, or seedlings, or the chest expansion, grip (right and left hands), or circumference 

 of arms. 1 



Record. Make a table showing the number of individuals for each count or measurement. Make 

 a graphic diagram to show the distribution of the variations in count or measurement (cf. Fig. 234 o 

 textbook). Describe what you have found. 



Questions. 1. How do you account for the differences that you find ? 



2. What striking examples of individual variation have come to your notice ? 



3. What is the practical importance of the fact that no two human beings are exactly alike ? 



1 It is possible that the school records can furnish a hundred measurements of some kind (for example, chest expansion),, 

 which may be made to serve. 



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