II 



THE PLANT CELL, 

 ITS MORPHOLOGY AND PHYSIOLOGY 



A. — The TJnicellulae Plauts 

 Example 1. — Yeast {SaccTiaromycea Sp.) 



Material— Dissolve a small piece of a "compressed" 

 yeast cake in a little water, put a drop of the mixture 

 on the slide, and examine according to the directions 

 given for Protozoa. Or, a cake of dry yeast may be 

 soaked in water until soft and a drop of the mixture 

 taken for examination. If baker's yeast is obtainable 

 that may be used. In any case, disregard the starch 

 grains which will probably be present. They may be 

 recognized by being much larger than the yeast cells, 

 usually oval in outline, and by having striations on 

 their surface. Have at hand the magenta solution, five 

 per cent, potash solution, dilute iodine, Schulze's solu- 

 tion (dilute), a little corn-starch, a watch-glass, test- 

 tubes, distilled water, ten per cent, sugar solution, Pas- 

 teur's solution without sugar, Pasteur's solution with 

 sugar, Mayer's pepsin solution, water-bath, barium 

 hydrate, porous porcelain cup, litmus paper, moist 

 chamber, two Florence flasks, chemical thermometer, 

 teacup, alcohol lamp, dry plaster of Paris, camel's-hair 



