182 MYSTERIES OF THE FLOWERS 



tulips in form, but hanging gracefully downward. 

 Each flower has six white sepals and petals, form- 

 ing the bell, a long pistil exactly the shape of a 

 bottle with an opening down through the neck 

 leading to the ovary within, and six stamens set 

 about the pistil, but all of them much too short to 

 scatter pollen upon its tip, nor would the pollen 

 take effect if placed there. 



It is the exceptional and extraordinary feature 

 that its pollen must be forced down the neck of the 

 bottle and into the ovary, in order to vivify the 

 ovules within. No happy accident will do this; 

 and there is only one insect that will. It is a moth 

 known as the Pronuba Yuccasella, the only moth I 

 know of which is provided with a pair of jaws for 

 the work. From "The Moth Book" I copy the 

 following description of the creature and its con- 

 duct: 



"No discovery in recent years has been more in- 

 teresting to students of insect and plant life than 

 that which was made in 1872 by Professor Riley, 

 of the intimate relationship which subsists between 

 the beautiful plant known as Yucca, and the genus 

 of moths to which the present species belongs. It 

 has been ascertained that the fructification of the 

 various species of Yucca is almost absolutely de- 

 pendent upon the agency of the female moth ; and, 



