4 BULLETIN 925, U. S. DEPARTMENT OF AGRICULTURE. 



Table I. — Measurements of maize plants of two sister progenies, one of which 

 was brachytic and the other normal in stature. 



Plant character. 



Height of plant decimeters. 



Number of leaves: > 



Above the upper ear 



Total 



Number of branches in the tassel 



Ear length: 



Upper ear centimeters. 



Total do. . . 



Number of rows on upper ear 



Diameter of stalk iVinch . 



Fourth leaf from top: 



Length centimeters . 



Width do. . . 



Braehvtic. 



8.66±0.10 



3.20±0.08 

 22.90±0.19 

 15.30±0.64 



14.20±0.27 

 27.60±0.98 

 16.30±0.26 

 20.50±0.35 



62.60±6.20 

 9.20±1.40 



Normal. 



14.40±0.24 



3.37±0.09 

 20.80±0.27 

 25.90±1.01 



16.40dz0.23 

 2S.10±0.71 

 21.20±0.30 

 12.40±0.21 



64.40±8.90 

 12.30±1.50 



The range in height of the brachytic plants was from 6 to 10 

 decimeters with a coefficient of variability of 10.1+0.81. Nine hand- 

 pollinated ears were obtained from these brachytic plants, from 

 which progenies were grow T n the following season (Table II). In 

 five cases colored and white seeds were planted separately, making 

 14 progeny rows. Since no differences were found between the 

 plants grown from seed of the two colors, they may be considered as 

 single populations. The progenies from seeds of different colors of 

 the same ear are grouped together in the table. In each pair the 

 progeny grown from white seeds appears first. The differences in 

 height between the progenies were for the most part insignificant, 

 and while the measurements are given separately in Table II, it would 

 seem not unfair to consider them as a single population. The num- 

 ber of individuals is then 286 with a mean height of 8.81 ±0.046. The 

 range in height is from 5 to 13 decimeters with a coefficient of vari- 

 ability of 13.1 ±0.37. 



The progenies differed somewhat in appearance, some having stiff 

 erect leaves while in others the leaves were long and drooping, like 

 those of the plant shown in Plate I. They differed also in produc- 

 tivity, the best-yielding progeny exceeding the poorest by more than 

 100 per cent. The diversity among the progenies, however, was no 

 greater than is ordinarily found among sister progenies of normal 

 stature. 



All but one progeny had about 25 per cent of the plants with 

 aborted male inflorescences (PL III). The degree of abortion varied 

 from plants having a few of the branches aborted at the tips or per- 

 haps several short naked branches to those which aborted all the 

 tassel branches or bore only undeveloped spikelets. The progenies 

 also varied in the percentage of affected plants, but for the 274 plants 

 involved 27±1.81 per cent showed this abnormal behavior. 



The abortion of the male inflorescence did not affect the female 

 inflorescence, and the yield of such plants was as great as that of un- 



