120 GERMINATION OF THE MICROSPORE 



you will see that a corresponding plant appears in the ferns and 

 other groups of plants. 



Returning now to the microspore, we find that its germination 

 also often begins while in its sporangium but in other cases 

 growth begins after it has escaped from the sporangium and has 



FIG. 78. The germination of the megaspore complete. The plant thus 

 formed consists of a female gamete or egg cell, 9 , below which are two syner- 

 gidae and in the center are the two uniting polar nuclei, p, while at the opposite 

 end of the sac are three antipodal cells, a; mi, micropyle; i, integuments; /, 

 stalk or funiculus in which a vascular bundle, v, has been developed to trans- 

 port food from the plant to the ovule. 



been carried by the wind or some insect visiting the flower for 

 food, to the stigma of the pistil. The stigma is admirably 

 adapted to hold the microspores, being provided with minute out- 

 growths, and frequently sugary solutions are exuded which fasten 

 the spores to the stigma. The real importance of these sugary 



