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Amer. Scientist 44: 229-247. 



HENDRICKS, S. B. 



1957. the clocks of life. Atlantic 

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hicks, c. b. 



1957. you can make a plant do tricks. 

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1957. GARDENING INDOORS UNDER LIGHTS. 



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DEMONSTRATIONS 



A. Light and Seed Germination 



DEMONSTRATION A-l : Effect of light on germination of seeds planted in soil. 



MATERIALS: 



Seeds of peppergrass (Lepidium virginicum or L. densiflorum) . 

 Sterilized potting soil. 



Six clay pots, or other suitable containers, 3 to 4 inches in diameter. 

 Small glass squares large enough to completely cover the tops of the pots. 

 Glass baking dish or enameled pan large enough to contain all the pots. 

 Pot labels. 



PROCEDURE: 



1. Fill six pots or containers with moist (not wet) sterilized soil to within 2 centimeters of the top of the 

 pots. Smooth the soil surface and tamp the soil gently but firmly with the bottom of one of the pots. 



