REPRESENTATIVE PLANTS 



A MANUAL OF BOTANY 



PART I 



A DETAILED STUDY OF SEED PLANTS, WITH 

 APPLIED OR EXPERIMENTAL BOTANY 



SECTION I. A STUDY OF SEEDS AND SEED PROBLEMS 

 1. The Beax Seed. A Dicotyledox 



General statement. Seeds of navy, red, kidney, and lima 

 beans, dry and soaked overnight, are to be carefnlly com- 

 pared, and the size, form, color, and external markings of 

 each observed. The difference in size, caused by the soak- 

 ing in water, is to be particularly considered. How has the 

 seed been increased in volume ? What similar familiar facts 

 are of common occurrence in tlie home kitchen ? How does 

 the water gain entrance to the seeds ? When a seed is 

 planted, what corresponding occurrence takes place ? 



External features. Examine the bean for three external 

 markings on the concave margin. The large central one is 

 the scar (hilam). Examine its surface with a lens. What 

 caused this scar ? Look closely with the lens near either end 

 of the scar. What do you find, and how do the two features 

 differ from each other ? One is the pore (microjvjle), and 

 the other is the blister (raphe or chalaza). These names are 

 truly descriptive, and pores and blisters are easily distin- 

 guished. 



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N. C. State College 



