10 Elementary Work in Botany. 



together and make a cross- section, cutting the caulicle near 

 its tip. Cut a fresh bean the same way and draw the sec- 

 tion. It must show the pocket, the caulicle, and the two 

 cotyledons. Write on or beside your diagrams the names 

 of all the parts shown, and show where the skin is thickest. 

 The positions in the first diagram of hilum, micropyle, and 

 chalaza should be indicated by dotted lines leading to them 

 from their names written at one side of the diagram. 



Take a sunflower seed out of its pod and remove the 

 coat. Why is the coat so thin ? Is there a pocket ? Why 

 not ? Break off one cotyledon and make a drawing similar 

 to that of the peanut on page 9. 



Taste the cotyledons of the bean and the sunflower. 

 Crush a bit of each kind on white paper. Put the unused 

 seeds in the cup and cover as before.* 



EXERCISE 4. 



Which of your seeds have sprouted ? What is the 

 sprout ? Where does it get out of the coat ? Is the point 

 very sharp or rounded ? Draw the seed which has the 

 longest sprout. 



Study the common bean and the scarlet runner as you 

 have the Windsor bean. Compare the plumules. How 

 many leaves can you see on the plumule stem ? How are 



* Your seeds will behave better if now you place them on a wet cloth or 

 paper in a pie tin or soup plate and cover with several thicknesses of wet cloth 

 or paper; or, better still, they may be put in wet redwood sawdust or sand. The 

 beans pinned to the stick in the jar should be those which have been soaked. 

 It will be all the better if \ hey have begun to sprout 



