Seeds and Seedlings. il 



25. Make a median longitudinal section through the 

 lesser diameter of seedlings in various stages of germina- 

 tion, and draw from the point of view of the cut surfaces. 

 The drawings should show definitely the changes which 

 the several parts undergo as germination progresses. 



26. Make cross sections of the stem of a well-advanced 

 seedling, and drawings to show how the leaves are 

 wrapped together, as shown by these sections. 



27. What are the differences in the details of growth of 

 Lima bean, castor bean, and Indian corn which result in 

 the grain of corn remaining below the ground in germina- 

 tion, while, in the beans, the bulk of the seed is lifted 

 above the ground .■" By what means does the corn seed- 

 ling obtain the food which is stored in the seed .' 



28. After the instructor has pronounced the drawings 

 of castor bean and Indian corn satisfactory, tint the dif- 

 ferent structures with the colored pencils, as in the case 

 of the Lima bean, using the same color for the correspond- 

 ing parts in all of the seeds and seedlings studied. 



General Comparisons. 



29. Make drawings on one page, for comparison, of the 

 seeds of Lima bean, castor bean, and Indian corn, select- 

 ing the point of view which best shows the different 

 structures, and with the colored pencils give the same 

 colors to the corresponding parts. 



30. In your notes briefly compare the corresponding 

 parts of the seeds studied. 



Experiments. 



31. With the sharp point of a penknife, scrape up a 

 small portion from the cotyledon of a soaked Lima bean 

 and mount in a drop of iodine solution (see page 387), on 

 a glass slip, and cover with a coverglass. Examine with 



