HAZEN: TRIMORPHISM AND INSECT VISITORS OF PONTEDERIA 473 
а. Long styled 
. 
b Mid-styled 
1------"---------....... 
с Short- sty!ed 
Fic. 11. Pontederia cordata; flowers of the three forms in approximately 
natural position (X 4). һе dotted lines with arrows indicate the six legitimate 
ith i d 
stamens with their inverted anthers and the short pistil. 
Drawn 28 August 1916. . 
