THE MICROSCOPE AND PLANT LIFE 



there are all manner of contrivances on the stigmas, 

 all designed for holding the pollen grains; hairs, 

 knobs, hooks and the like. 



An interesting collection could be made of various 

 pollen grains, which are easily obtained by merely 

 dusting the anthers of flowers on to a clean, dry 

 slide. They are varied in shape, colour and size; 

 some are smooth, some studded with spines, others 

 again, those of the Mallow for example, have little 

 lids which open when the pollen grain germinates. 

 The germination of pollen grains is easily observed 

 under the microscope, by putting a few of the grains 

 in an exceedingly weak solution of sugar and water. 

 The vigil may be a long one, but if the pollen grains 

 are ripe and fresh, and the sugary solution suffi- 

 ciently weak, the patience of the microscopist will 

 be rewarded by the observance of the bursting of 

 the pollen grain's coat and the outgrowth of the 

 pollen tube. 



Other pollen grains worthy of examination, are 

 those of various lilies, of Eschscholtzia and of 

 Scotch Fir; the last named have curious little air- 

 bladders, for the purpose of rendering them more 

 buoyant. 



Many lowly plants thrive in weak sugar solutions, 

 after the manner of pollen grains. The yeast plant 

 is one of them. A very small portion of yeast, in 

 a drop of sugar solution, will show us one of the 

 simplest methods of vegetable reproduction. Yeast 

 is a fungus and it is also a plant composed of only 

 one cell. Under the microscope, it appears as a 



107 



