DRY FRUITS TRANSPORTED BY 

 THEIR OWN DEVICES 



Of the many seeds that sail or float, the ones 

 best known are those of the Dandelion, the 

 Thistles, and the Milkweeds; in addition are 

 the Asters and the Goldenrods. All of these 

 with one exception are Composites; the flowers 

 in heads and the calyxes so compressed that the 

 body of the calyx is grown fast to the ovary, and 

 only the upper part is separate. This develops 

 into a number of delicate hair-like bristles, white 

 or tawny, which separate when the seeds are 

 mature and ready to fall from the protecting 

 involucre; the minute hairs spread out, and 

 there is a sort of parachute formed of suffi- 

 cient size and strength to bear the seed far 

 afield. With the bristles perfect, the seed well 

 weighted, and the wind not too strong, the airy 

 journey may be of considerable length. 



The structure of the fruit of the Milkweeds is 

 different, though the result is the same. The 



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