54 



TIIH POLLINATION OF PEAR FLOWERS. 



SUMMARY. 



The foregoing series of experiments furnisbcs repeated evidence of 

 the vakie of cross-pollination in pears for frnit prodnction. It was 

 found in case of more than half the varieties worked upon that they 

 were either entirely incapable of setting fruit when limited to their 

 own polleu, or so nearly so as to show them to be unsatisfactory 

 as self-fertilizers. Careful hand-pollinations, in wdiich different kinds 

 of pollen have been a|)plied to the same kinds of pistils under the 

 protection of paper bags, have shown the decided advantage of cross- 

 pollination, and have given results substantially agreeing with the 

 simple bagging experiments. ISlot all the varieties showed this defi- 

 ciency in iH'oducing fruit with their own pollen; some were quite pro- 

 ductive under its influence. Even with these varieties self-pollination 

 seemed to be less certain than cross-pollination and was less sat- 

 isfactory some seasons than others. The results have shown that 

 the varieties belong more or less distinctly to two classes, self-sterile 

 and self- fertile. 



Absolute reliance should not be placed in any particular one of the 

 statements in the synopsis, but where work was duplicated several 

 times and repeated in four different places and the general result con- 

 tinues the same the conclusion finally becomes assured. We give below 

 a list of the tw^o classes of pears, (1) those which are more or less 

 completely incapable of self-fertilization, and (2) those which have 

 sliown a more or less pronounced ability to self- fertilize: 



Self-sterile varieties. 



Self-fertile varieties. 



Anjou. 



Angouleme. 



Baitlett. 



Bosc. 



Boussock. 



Brockworth. 



Clairgeau. 



BuflYnn. 



Clapps Favorite. 



Diel. 



Colmnbia. 



Doyenne d'Alf iKjon. 



De la Chene. 



Flemish Beauty. 



Doj-enne Sieulle. 



Heatlicote. 



Easter. 



Iviefter. 



Gansels Eergamotte. 



Le Conte. 



Gray Doyenne. 



Mannings Elizubetli. 



Howell. 



Seckel. 



-Tones. 



Tyson. 



Lawrence. 



White Doyenne. 



Louise Bonne de Jersey. 



Mount Vernon . 





Pound. 





Sheldon. 





Souvenir du Congres. 





Superfin. 





Wilder (Colonel). 





Winter Ifelis. 





