CHAPTER XLVII. 



SEED DISTRIBUTION. 



457. Means for dissemination of seeds. — During late summer 

 or autumn a walk in the woods or a field often convinces us of 

 the perfection and variety of means with which plants are pro- 

 vided for the dissemination of 

 their seeds, especially when we 

 discover that several hundred 

 seeds or fruits of different plants 



Fig. 245. 

 Bur of bidens or bur-marigold, show- 

 ing barbed seeds. 



Fig. 246. 



Seed pod of tick-treefoil (desmodium); at 

 the right some of the hooks greatly magnified. 



are stealing a ride at our expense and annoyance. The hooks 

 and barbs on various seed-pods catch into the hairs of passing 

 animals and the seeds may thus be transported considerable 

 distances. Among the plants familiar to us, which have such 

 contrivances for unlawfully gaining transportation, are the 



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