EXERCISE 61 

 A MONOCOTYLEDONOUS SEED 



Materials. Seeds of corn which have been soaked for at least 

 twenty-four hours, and some which have been germinated on 

 blotting paper. 



Directions for work. Examine the germinated seeds to iden- 

 tify the plumule and the hypocotyl and root. Examine one of 

 the soaked seeds, and by comparison with the germinated seed 

 locate the general position of the plumule and the hypocotyl. 

 Then cut the seed in two lengthwise through the center so as 

 to split the young plant (embryo) from end to end. This can 

 best be done by making the first cut a little to one side of the 

 center and then carefully shaving off the cut surface until the 

 growing points are properly exposed. By the aid of illustrations 

 identify the cotyledon ("Practical Botany," Figs. 128, 129). 



In this case does the cotyledon come aboveground. ? Is the 

 food stored in the cotyledon or outside of it ? What office does 

 the cotyledon serve ? 



References 



BERGEN and CALDWELL. Practical Botany, p. 137, Figs. 127-129. 

 BERGEN and CALDWELL. Introduction to Botany, p. 158, Fig. 143. 



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