New York Agricultural Experiment Station. 33 



conducted at this Station since 1892, and in 1897 the tests were 

 repeated with several varieties in two localities in the vineyard 

 region of Western New York. 



One hundred and sixty-nine cultivated varieties have been in- 

 cluded in these tests together with a few vines representing uncul- 

 tivated native species. Eleven species have been under investiga- 

 tion. 



Different kinds of flowers are found with the grape, Vitis, but 

 each vine normally bears only one kind. The so-called male 

 vines produce no fruit for they bear staminate flowers only, having 

 no pistils or, at most, rudimentary pistils. These flowers have 

 long stamens. All fruitful vines bear perfect flowers, having both 

 stamens and pistil. These may be separated according to the struc- 

 ture of their flowers into three classes, those with short, recurved 

 stamens, those with long, upright stamens, and those with stamens 

 intermediate between long and recurved. 



'Flowers with long stamens are structurally adapted to insure 

 self-pollination. The short, recurved stamens do not favor close 

 pollination. 



Forty-seven varieties having short stamens were tested for self- 

 fertility. When cross-pollination was prevented only eight set 

 any fruit, and none of these formed perfect clusters. In many 

 cases varieties having long stamens were self-sterile, the pollen 

 being self-impotent. Short stamens are, so far as known, a relia- 

 ble indication of partial or complete self-sterility. It cannot be 

 said that long stamens are a sure indication of self-fertility. 



Lists of self-sterile, partly self-fertile and self-fertile varieties 

 based on the experiments referred to are published in a bulletin. 

 When self -sterile or partly self-fertile varieties are cultivated they 

 should be mingled with other varieties so as to favor cross- 

 pollination. 



Tables have been prepared from the records of the Station vine- 

 yards whereby the date of blooming of the different varieties may 

 be compared. This will assist those who wish to grow any of the 

 . 3 



