64 



color, size, and grouping of the flowers, and the abundance 

 and accessible position of the pollen and honey." 



In the Rocky Mountains this species is eomttionly visited 

 by several species of Bonbus- i - 



FIG. 27. 

 Pig. 27. Dlchogamous flowers. 1 Ppiiohium angustifolinm showing devel- 

 opment of stamens first (proterandrous) witli a bumble beeou one of the flow- 

 ers. See upper flowers. (After Earner von Marilaun.) 



The Cucurbits are usually said, to be mou- 



oecious or dioecious, although w. U. 



Mueller says occasionally polygamous. It has been known 



for some time that the same species are proterogynous and 



