CHAPTER III. 



THE LIVING SUBSTANCE OF PLANTS. 



I. PROTOPLASM IN ROOT HAIRS OF SEEDLINGS. 



33. Importance of studying protoplasm. Now that we have 

 become familiar with the parts of the seedling, have studied the 

 germination of the seed, and have observed the increase in size 

 and elongation of its parts we are impressed with the fact that it 

 is a living thing. It is now time to inquire into the nature of 

 the living substance of plants. Plant growth as well as some of 

 the other life processes which we are about to study are at 

 bottom dependent on this living matter. It is evident, then, 

 that we should know something about it, how it appears, and 

 how it acts. For with this knowledge it is easier to comprehend 

 how the plant does its work as a living being. This living sub- 

 stance of plants is protoplasm. The student should now observe 

 protoplasm in several plants. If there are not a sufficient num- 

 ber of microscopes to enable the students to make and study 

 their own preparations, let the teacher prepare a demonstration 

 for the members of the class. 



Demonstration 2. 



34. To prepare seedlings with clean root hairs. Begin to prepare the 

 seeds several days or a week before they are wanted for study. Soak a 

 handful of corn or beans, radishes, etc. (or more if there is a large class) in an 

 abundance of water for 24 hours. Prepare a moist chamber by placing a 

 layer of moss (sphagnum) or cotton in the bottom of a wide vessel (a crockery 

 plate or a germinator with a fluted bottom). Upon this place a layer of filter 

 paper. Have the sphagnum and filter paper well wetted, but not with a sur- 



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