1908.] 



IMPROVEMENT OF THE POTATO. 



443 



SELECTIONS FOR PLANTING, 1903 



The experiment was continued in 1903, with the variety Early 

 Ohio, which was considered to give better yields on Illinois soil. 

 Unfortunately, the seed tubers which were obtained had been grown 

 in southern Illinois on soil of an entirely different type from that 

 upon which they were to be planted in the experiment, and there is 

 no means of knowing whether the stock was adapted to the latter 

 type. 



These potatoes were of different type from those used in 1902. 

 the Early Ohio being oblong-cylindrical. The average weight was 

 smaller and the cooking quality poorer than those of the previous 

 year. They were slightly infected with scab, but were fairly typ- 

 ical of the variety. 



Two hundred nineteen individual tubers were analyzed in the 

 same manner as those of the year before, with the result that fully 

 as great variation in individuals was found in this variety. 



Comparing the two varieties used (1902 and 1903), which of 

 course is not strictly fair, owing to their being the product of dif- 

 ferent soils and seasons, it is seen that the higher average dry mat- 

 ter is shown in the round-flat variety, which is in accord with 

 Fischer's theory. 



The dry matter fluctuations were from 10.55 percent to 30.96 

 percent, with an average of 16.15 percent and a mode between 

 16.0 percent and 17.0 percent. 



TABLE 20. VARIATIONS IN DRY MATTER. (CROP OF 1902, EARLY OHIO) 



The average nitrogenous matters, calculated to fresh basis is 

 2.43 percent, and calculated to water free basis is 15.21 percent. 

 The variations in total nitrogenous matter are shown in the fol- 

 lowing table : 



