146 



PEACTICAL BOTANY 

 SEED DISTRIBUTION 



135. Usefulness of the seed. People in general, no matter 

 how familiar they may be with seeds, do not stop to consider 

 what the seed means in the perpetuation of any species of 



FIG, 135. Fruits of Spanish needles (Bidens) 

 Natural size and twice natural size 



plant. Some seed plants, it is true, manage to perpetuate 

 themselves for an indefinite tune by vegetative methods, as 

 by root buds, by various kinds of stem propagation, or even 



