no THE BRACKEN-FERN. 



other. Enclosed by the fibrovascular region is a mass of 

 axial sclerenchyma whose cells resemble those seen in 2. 



4. Diagram the entire section and draw in detail a narrow 

 strip across it, so as to show all the kinds of tissues. Make 

 a longitudinal section of the stem, and identify: 



5. The various regions observed in the cross-section. Draw. 



II. THE ROOT. 



Make a transverse section of one of the larger roots, study 

 it, and make a diagram, showing: 



1. The epidermal region. 



2. The parenchyma, composed of cells of approximately equal 

 dimensions. 



3. The sclerenchyma, resembling that of the stem. 



4. The fibrovascular bundle and its bundle-sheath. No- 

 tice the starch stored in the above tissues. Select some 

 roots with uninjured tips and make longitudinal sections 

 of the tip. 1 Observe: 



5. The layers of the root-cap. 



6. Under the root-cap in the median section a large triangular 

 cell, apex inward, the apical cell. Notice that the cells 

 adjacent to the inner faces of the apical cell have evidently 

 been derived from it by partitions parallel to its faces. 



7. Draw the tip of the root, including the apical cell and the 

 root-cap. 



III. THE LEAVES. 



i. Epidermis. Lift the epidermis of the lower surface with 

 the point of a needle or scalpel, seize it with fine forceps 

 and strip off a small piece, mount it with the outer sur- 

 face upward, and observe: 



a. The very irregular epidermal cells and the way they 

 dovetail into one another. 



1 The best results will be obtained if .serial microtome sections are 

 at hand. 



