ORNAMENTAL PALMS 257 



BIGNONIA, WISTARIA, AND BELLFLOWER 



There are two or three other groups of vines 

 that must be given at least passing notice. 



One of the interesting forms with which I have 

 done much work is the class of climbing shrubby 

 plants of North and South America of the genus 

 Bignonia. By crossing some of the bignonias 

 with the Tecoma, a plant that grows wild in Vir- 

 ginia and Maryland, some interesting results 

 were brought forth. 



There was modification of color of flower, 

 length of seed pods, and vigor of growth of the 

 plants themselves. But no variety was secured 

 that seemed worthy of special introduction. 



An interesting feature of the hybridizing ex- 

 periments with the bignonia is associated with the 

 curious sensitiveness of the stigma of the flower 

 to irritation. The two lips of the stigma stand 

 open, like a set trap, and when pollen is sup- 

 plied they close, traplike, grasping it instantly. 

 Anyone who has never seen the lips of the stigma 

 of the bignonia close when irritated by bees or 

 artificial means would be greatly surprised. 



It is necessary in applying the pollen to 

 be somewhat dexterous, lest the lips of the 

 stigma close and make the stigmatic surface 

 inaccessible. 



Vol. 7 Bur. I 



