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CHAPTER V 



GERMINATION OP SEEDS 



42. Introductory. In the preceding chapters the struc- 

 ture and the work of the three great nutritive organs (leaf, 

 stem, and root) of the higher plants were considered. In 

 studying the germination of seeds, these organs may be 

 observed assuming their various positions and relations, and 

 the student may be introduced to certain important facts. 



FIG. 81. Section of bean; removing one cotyledon, and showing the testa, the 

 remaining cotyledon, the hypocotyl (its tip in position to emerge), and the 

 plumule. 



Perhaps the most common seed used in class study of seed 



germination is the garden bean, although other seeds should 



be germinated in the laboratory, and, when possible, studies 



of germination should be extended beyond the laboratory. 



43. General structure of the seed. It is very common 



to study even the surface of the seed in great detail, but 



84 



