1 68 The Great World's Farm 



When the pollen is ripe, that is, ready for the use of 

 the grains contained in the pistil, the chambers open and 

 it is discharged. The pollen consists of hollow grains, 

 varying very much in size and shape in different plants, 

 though always alike in the same plant. 



Pollen-grains are very beautiful objects v/hen seen 

 through the microscope, though they look like nothing but 

 powdery dust to the naked eye. Their color is usually 

 yellow or brown, but they are also red, green, blue, whit- 

 ish, and even black; and though their general shape is 

 round, or egg-shaped, they are of many other forms, 

 wonderful in their great beauty and variety, and reminding 

 one of microscopic shells. 



Some pollen-grains, for instance, are covered with 

 ridges or grooves; others, such as those of the hollyhock 

 and aster, with spines; others again with hairs or thorns; 

 those of the thistle are many-sided; of the fuchsia and 

 evening primrose, triangular; of the chicory, six-sided; 

 and if we could see, we should no doubt find a reason 

 for every change of form and color, and discover that each 

 was exactly adapted for its own special purpose. 



Every pollen-grain is delicately coated with oil, prob- 

 ably as a protection against damp and wet, and all have 

 upon them markings, like pores or slits, to some of which 

 there are lid-like covers. Usually each grain consists of 

 a single cell, though sometimes there are more, and the 

 cells are filled with a liquid of a most nutritious kind, con- 

 sisting partly of starch, partly of oil, and partly of some 

 jelly-like nitrogenous compound. 



It is pollen which is the flesh-forming food of the bee. 

 It may live on honey, which is mainly sugar — not nitroge- 

 nous — during the winter, when it is doing no work, but 



