I^Ew York Agricultural Experiment Station. 437 



The influence of crossing is very apparent in this table — 

 the Fi generation cross surpassing both the parents and the other 

 crosses in yield. The Fo generation stands second in pro- 

 ductivity and the F3 and F4 generations fall below the yield of 

 the Livingston Stone. The number of heterozygous individuals 

 in the third and fourth generations are not known, but they are 

 probably few in number (see discussion on page 66). 



DISCUSSION OF RESULTS. 



It is well known that it is often unfair to draw conclusion 

 on the yield of an acre, based on the performance of a few plants, 

 but when the results are repeated for three consecutive seasons, 

 under good and adverse conditions, and the gain is consistent, 

 one may assume that the results are not a case of chance. Further 

 the results are supported by similar performances of many other 

 similar experiments on various genera and species (see 

 Introduction) . 



The summer experiment of 1908 gave gains which favored 

 the crosises to a marked extent. The Dwarf Aristocrat x Living- 

 ston averaged 4.438 pounds more fruit per plant than the Living- 

 ston Stone and 10.558 pounds more fruit than its maternal par- 

 ent, or in other words, if the plants had been set 4 feet by 4 

 feet, that is, 2,722 to the acre, we would have obtained about 

 six tons more fruit from this cross than from the Livingston 

 Stone and over fourteen tons more fruit than from Dwarf Aristo- 

 crat. If the cross had been made between two standards, instead 

 of a dwarf and a standard, the yield might have been greater, 

 but perhaps not, as the vines of the first generation are standard 

 in size. 



The winter experiment of 1908-1909 is not comparable with 

 the summer experiment, as the conditions are very different, and 

 in addition, the same generations were not grown. 



The summer experiment of 1909 gave lower yields for all the 

 lots than the previous season, and this fact may be partially 

 explained by the unusual drought which prevented the maximum 



