ON SOME ORNAMENTALS 



One of the interesting forms with which I have 

 done a good deal of work is the tribe of climbing 

 shrubby plants of North and South America of 

 the genus Bignonia. I have hybridized some 

 species of bignonia with several of the Tecoma, a 

 plant that grows wild in Virginia and Maryland. 



The resulting vines were variable, and had a 

 fair degree of interest. 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 introduction. 



An interesting feature of the hybridizing experi- 

 ments 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 supplied they 

 close, trap-like, grasping it instantly. Anyone who 

 has never seen the lips of the stigma of the big- 

 nonia 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. 



Nor may the lips be pried apart. They open 

 spontaneously, however, after a time, but usually 

 not until the patience of the operator has been 

 exhausted. It is a curious and interesting experi- 

 ment to irritate the stigmatic surface with a grass 



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