302 



STRUCTURE OF LEAVES 



Spencer Lens Co., Buffalo. 



Williams, Brown & Earle, Philadelphia. 



Geneva Optical Co., Chicago. 



Whitall, Tatum & Co., New York. 



Chas. Lentz & Sons, Philadelphia. 



Kny-Scheerer Co., New York. 



Cambridge Botanical Supply Co., Cambridge, Mass. 



475. All material and apparatus should be kept under cover when not in use. 



The microscope should have a 1-inch and perhaps a 2-inch eye- 

 piece, and two objectives of say % and K focal lengths. By arrang- 

 ing the laboratory study of the pupils at different times, each microscope 

 may be used by three, four, or even more pupils. 



There should be a microtome or section-cutter for use by the class. 

 If possible, each pupil should have his own individual tools and 

 bottles of reagents, as follows: 



1 good razor (hollow-ground on one side only). 

 1 small scalpel. 



1 pair forceps. 



2 sharp needles mounted in handles (as penholders). (Fig. 215). 

 1 medicine dropper. 



1 small camel's-hair brush. 

 A number of slides and cover-glasses. 

 Of reagents, stains, and other chemicals, there should be the following : 





Glycerine. 



95 per cent alcohol. 



Canada balsam. 



Xylol. 



Copper sulfate solution. 



Iodin dissolved in water. 



Iodin dissolved in alcohol. 



Potassium hydroxide solution. 



Fehling's solution. 



Alcanna (henna root in alcohol). 



Formalin. 



Preparing and keeping laboratory material. — In preparing material 

 for the experiments outlined in Part III, the pupil or teacher will find 



