640 



Joitrnal of Agricultural Research 



Vol. XII, No. 10 



Table X. — Degree of setting of the fruits of various positions on the inflorescence on 

 hermaphroditic varieties and jp seedlings of strawberries when bagged — Continued 



Variety. 



Seedling 40 - - - - ' 2 



Seedling 168 | 2 



SeedlingsSs ' 2 



Seedling 753 [ " 2 



Seedling 876 



Seedling 703 



Seedling 778 



Seedling 937 



Seedling 1065 



Seedling 1009 



Seedling 845 



Seedling 901 



Seedling 1018 



Seedling 1017 



Seedling 585 



Seedling 702 



Seedling 753 



Seedling 778 



Seedling 776 



Seedling 908 



Seedling 923 



Seedling 924 



Seedling 937 



Seedling 947 - 



Seedling loio 



Seedling 101 7 



Seedling 1023 



Seedling 1026 



Seedling 1045 



Splendid XDunlap 



Total.... 

 Per cent . 



Primary. 



113 

 26.8 



48 

 II. 4 



Secondary. 



28s 

 24.9 



624 

 54.6 



234 

 20.5 



Tertiary. 



337 



21-5 



587 646 

 37. 441. 1 



Quaternary. 



70 

 II. 8 



114 

 19. 2 



Total. 



a Two bags split or tip open, allowing the possibility of cross-pollination. 



Pollination in unbagged flowers is for the most part dependent upon 

 bees and small insects and upon the anthers becoming erect and partially- 

 folding about the receptacle while dehiscing, thus dropping the pollen 

 on the stigmatic surfaces. In the bagged flowers the insects are elimi- 

 nated, and thus the most efficient natural means of pollination is lost. 

 As a consequence many of the bagged varieties produced many nubbins, 

 but no case of complete self-sterility was found where morphologically 

 perfect pollen was present. 



If the percentages of total perfect fruits, nubbins, and sterile flowers 

 of each flower position in Table IV are compared with those in Table X, it 

 will be seen that (i ) the setting under bags is very much poorer than in the 

 open, both with regard to the number of perfect fruits set and also with 

 regard to the actual number of flowers which set any achenes, and (2) the 

 primary flowers are decidedly more fertile than the later ones, as, even 

 under the adverse conditions of pollination within the bags only ii.o 

 per cent of the primary flowers were sterile, while 20 per cent of the 

 secondary. 40.7 per cent of the tertiary, and 68.5 per cent of the quater- 

 nary flowers were sterile, in spite of the very great increase in amount of 



