168 Modern Microscopy 



LESSON VII. 



CUTTING, STAINING, AND MOUNTING 

 VEGETABLE SECTIONS. 



Stems, leaves, roots, etc., should be hardened in methy- 

 lated spirit for a week or ten days, and the spirit changed 

 every twenty-four hours for the first three days. The stems 

 must not be too old. One, two, and three years' growth will 

 show all that is required. 



Wheat, barley, maize, peas, etc., are usually obtained 

 dry. They must be placed in water for a few hours or 

 until they resume their natural shape. Then lay a piece 

 of blotting-paper on a plate, moisten it with water, and 

 spread a layer of the grains on its surface ; now place 

 another piece of wet blotting-paper over all, and put in a 

 warm place for from twelve to twenty-four hours, so that 

 the embryo may begin to germinate. Then remove from 

 the plate, and place the grains in a bottle of methylated 

 spirit, which must be changed every day until all trace of 

 water is removed. The specimens may then be sectionized 

 or they may remain in spirit until required. 



Ovaries. — Gather some before the flower opens, and 

 others after it has been open for a day. You will then have 

 the ovules in both stages. Place them in methylated spirit 

 and change every twenty-four hours for the first three 

 days. 



Anthers. — Treat in exactly the same way as ovaries, but 

 anthers must be infiltrated with celloidin before the sections 

 can be cut. Eemove the ends, place in equal parts of 

 alcohol and ether, and soak for twelve hours ; then place 

 in celloidin, and, after soaking for from twelve to twenty- 

 four hours proceed as directed in Lesson No. II. on Section 

 Cutting. 



Some specimens after being in spirit are too hard to cut 

 easily. They may be softened by soaking in warm water. 

 Leaves are often particularly troublesome in this respect ; 



