HISTOLOGY. 31 



8. Sectioned ; embeding material taken out ; then the 

 tissue fixed on the slide, stained, mounted and labeled. 

 After the student has carefully done this he will not 

 have any trouble. 



Exercise No. 17. 



1. Applr to the slide a section of the outer skin of 

 an onion -bulb. (Apply the section and add the stain.) 



2. Wash in water to remove the excess of stain. 



3. Dry with blotting paper; add a dehydrating me- 

 dium. 



4. Wipe off the dehydrating medium, which is usu- 

 ally glycerine. 



5. Add xylol. 



6. Apply balsam 1 to the section and place cover-glass 

 on the section balsam downward. 



7. Label and keep in a horizontal position until bal- 

 sam hardens (or study at once). Make out all you 

 can about cells in this preparation; /. e., shape, size, 

 contents and motility. 



Exercise No. 18. 



Make a preparation similar to that above and apply 

 a drop of iodine solution arid examine. Now remove 

 the cover and apply a drop of sulphuric acid. The 



