56 HOW TO USE THE MICROSCOPE 



a high power must be used. These three plants are 

 commonly cultivated in aquaria. 



The " revolving globes " of Volvox globator are 

 among the greatest marvels of pond-hfe. A full- 

 grown globe will be about t;V inch in diameter. If 



Fig. 19. — A few Cells feom the Leaf of the American 

 Water- Weed. 



a, b, c, d, e, Nuclei of the various cells ; /, a strand of protoplasm 

 crossing the cell-cavity ; (j, h, i, chlorophyll granules, some of 

 which are dividing. The small bodies inside the chlorophyll 

 granules are starch . (After Kny. ) Magnified several hundred times. 



we have been fortunate in our pond-hunting, we 

 may see a number of these tiny marvels revolving 

 freely in a rather majestic fasliion in one of our 

 store tubes. Let one or two be transferred to a 

 glass slip, with a concavity in the centre (such slips 

 are bought from dealers at about 2d. each). The 



