Fig. 116. Plowers of yucca visited by the moth Pronuba 



The work of the moth is suggested by its position in tlie several flowers. In the 

 first flower (the lowest), the moth is gathering pollen; in the second, slie is polli- 

 nating the stigma ; in the third, she is in the position of rest during the day ; in 

 the fourth, in the position of rest when disturbed ; in the fifth, ovipositing 



128 



