158 Clyde E. Leighty 



TABLE 14. Means, Standard Deviations, and Coefficients of Variability (concluded) 



Average weight of straw per culm of plant, iii decigrams 



68 , 102 118 



M 5.963 ± .084 3.767 ± .087 2.103 ± .052 



ff 2.167 ± .060 2.243 ± .062 , 1.341 ± .037 



C 36.34 ±1.12 59.54 ±2.14 63.77 ±2.36 



Average number of spikelets per culm of plant 



68 102 118 



M 17.027 ± .267 9.227 ± .215 4.707 ± .118 



<y 6.857 ± .189 5.523 ± .152 3.023 ± .083 



C 40.27 ±1.27 59.86 ±2.16 64.22 ±2.39 



Average number of kernels per spikelet of plant 



68 102 118 



M ^.013 ± .012 2.135 ± .015 2.046 ± .012 



ff 311 ± .009 .379 ± .010 .312 ± .009 



C 15.45 ± .43 17.75 ± .50 15.25 ± .43 



Breaking strength of straw, in grams 



68 102 118 



M 209.346±3.1C0 84.534±1.985 58.400±1.475 



ff 79.696 ±2.192 51.036 ±1.403 37.930 ±1.043 



C 38.07 ±1.19 60.37 ±2.18 64.95 ±2.43 



Considering first the average yield of culm per plant in decigrams, 

 it is seen in Table 13 that the mean for series 63 is 6.063 ± .108, for series 

 100 it is 2.630 ± .065, and for series 122 it is 1.917 ± .047. It is evident 

 that the yield per culm averages higher for plants grown in the less crowded 

 conditions. Without repeating here the means for the other line, the same 

 results are seen to hold in this. As to variability, considering the 

 standard deviation to be in such cases the best index, it is clear that the 

 variability in yield of culm per plant is greatest in the plants grown under 

 the least crowded conditions. The standard deviations for series 63, 

 100, and 122, are, respectively, 2.469 ± .076, 1.665 ± .046, and 1.215 

 ± .033. The other line exhibits about the same decrease in standard 

 deviations from the least to the most crowded condition. 



It will probably be well to take up separately the remaining characters 

 considered, but without repeating in the text the constants recorded in 

 the tables unless some unusual circumstance exists. Reference can be 

 made to the tables for the constants on which conclusions are based. 



