No. 572] THIRTEEN YEARS OE WHEAT SELECTION 463 



Selection to Decrease Neck-Lengths 

 The result of the selection for short neck-lengths is 

 shown in Table III. This is a clear illustration of how 

 misleading short-term experiments may be. Had the 

 experiment been discontinued at the end of the third year, 

 the figures would have indicated that it was possible to 

 modify this character very rapidly by selection. How- 

 ever, in the following two years the neck-lengths seemed 

 to revert to the mean of the pure lines, and the last year 

 they were actually longer than when the experiment was 

 started. The reduction in the first three years was prob- 

 ably due to growing conditions. 



TABLE III 



Discussion 



From the data presented in these tables, it is evident 

 that there has been no permanent gain for these thirteen 

 years of selection either in yield per plant, height of 

 plant, or shortening of neck-lengths. The expected sea- 

 sonal variations occur. A comparison of the yield of 

 Haynes Blue Stem, which is grown extensively in Minne- 

 sota, and was continued in the variety test without any 

 attempt at selection throughout the whole period, with 

 Hutcheson ('13). 5 



2 Love, H. H., "A Study of the Large and Small Grain Question," An. 

 Sep. Am. Br. Asso., 7: 109-118, 1911. 



a Myers, C. H., "Variation, Correlation and Inheritance of Characters of 

 Wheat and Peas," Cornell University Thesis, 1912. 



* Hutcheson, T. B., "Correlated Characters in Arena satira, with Special 

 Reference to Size of Seed Planted," Cornell University Thesis, 1913. 



sLeighty, C. E., "Studies in Variation and Correlation of Oats, Avena 

 sativa," Cornell University Thesis, 1912. 



