Photos: J. J. Ward. i 2 



RIPE FLOWER-HEAD OF THE GOAi's-BEARD (Tragopogon pratensis] 



(l) Ripe flower-head of the Goat's-beard (Tragopogon pratensis) commencing to open, 

 The flower-head in composite flowers, such as dandelion and thistle, consists of numerous 

 florets. At the base of each is a nutlet-like ovary, and in this, after pollination, a seed de- 

 velops. On each nutlet there grows a tuft of hairs (pappus), which serves as a parachute 

 when the fruits are ready to be scattered by the wind. In the Goat's-beard the hairs of the 

 so-called pappus are hygroscopic, changing their position according to the moisture in the 

 air. (2) Ripe flower-head of the Goat's-beard a day later. 



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(3) Ripe flower-head of the Goat's-beard on the third day. (4) Ripe flower-head of the Goat's-beard on the fourth day. (5) 

 Ripe flower-head of the Goat's-beard fully expanded with the fruits ready to be floated away by the wind and thus sown, often at a 

 distance. As the flower-head is in process of ripening moist weather affects the pappus hairs in such a way that the whole inflorescence 

 closes up and is thus kept dry. Each parachute is like dandelion-down, beautifully constructed, and obviously suited for aerial 



transport. 



