VARIABILITY IN LINKAGE OF CHARACTERS OF MAIZE 
31 
pollen is stored for several hours an excess of waxy seeds results. 
The second combination G c wx wx X c c Wx ivx, which corresponds 
to Brink's case where a deficiency of waxy seeds was found, is shown 
in Table 19. Obviously there is no difference between the percentage 
of waxy seeds obtained with this combination and that obtained 
when the noncrossover combination was used, the percentage found 
in the former case (Table 18) being 45.98 ±0.44 and in the latter 
(Table 19) 45.96+0.27. 
Further evidence on this point is found in summarized form in 
Table 15, an inspection of which shows that the percentage of waxy 
seeds is not affected by the nature of the aleurone factors C and B 
when the percentages of waxy in entries 3 and 4 are compared with 
those in entries 1 and 2, nor by the nature of the cross, that is, 
whether between crossover or noncrossover classes when the per- 
centage of waxy in entry 5 is compared with entry 7 and entry 6 
compared with entry 8. 
Table 19. 
-Reciprocal crosses of colored waxy (C c wx ivx) X wJiite Jvorny 
(c c Wx wx) 
Reciprocal cross 
White horny, female 
Number 
of seeds 
Percentage 
of white 
Percentage 
of waxy 
Colored waxy, female 
Number 
of seeds 
Percentage 
of white 
Percentage 
of waxy 
3882X3776 
290 
3885X3787- 
180 
3888X3778 
515 
3892X3784. . 
150 
3895X3787-2. 
61 
3898X3793 
97 
3900X3789 
414 
3907X3802 . 
592 
3907-2X3801-.- 
224 
3909X3804. 
447 
3916X3808 
505 
3916-2X3808-2. 
585 
3919X3806 
438 
3922X3803... 
419 
Mean.. .. 
46. 6±1. 98 
53. 9±2. 50 
49. 1±1. 48 
51. 3±2. 75 
41. 0±4. 24 
46. 4±3. 41 
47. 6±1. 65 
45. 3±1. 38 
50. 0±2. 25 
45. 9±1. 59 
51. 5=1=1. 50 
48. 4±1. 39 
47. 3=fcl. 60 
50. 8=1=1. 64 
48. 34± . 44 
53. l=kl. 98 
41. 7±2. 47 
48. Oil. 48 
44. 0±2. 72 
57. 4=1=4. 26 
48. 4=1=3. 42 
51. 7±1. 65 
49. 5=1=1. 38 
54. 0±2. 24 
48. 5±1. 59 
51. 7=1=1. 50 
50. 1±1. 39 
48. 4=1=1. 60 
50. 4=bl. 64 
49. 75=fc . 48 
189 
198 
538 
72 
589 
26 
510 
445 
450 
628 
416 
360 
550 
256 
47. 1±2. 45 
57. 6±2. 37 
44. 8=1=1. 45 
54. 2=1=3. 96 
51. 3±1. 39 
53. 8=1=6. 58 
45. 1±1. 49 
46. 5=fcl. 59 
52. 2=bl. 58 
47. lil.34 
49. 8±1. 65 
50. 3=1=1. 77 
49. 4±1. 44 
45. 7=b2. 08 
47. 1±2. 45 
48. 5±2. 39 
45. Oil. 45 
43. 1=1=4. 27 
45. 8±1. 38 
38. 5±6. 42 
47. 6±1. 49 
46. 1±1. 59 
43. ld-1. 57 
45. 5±1. 34 
46. 9±1. 64 
46. 4±1. 77 
45. 6=1=1. 43 
48. 4±2. 10 
. 48.67± .56 • 45.96± .27 
CROSSING OVER REDUCED BY THE R ALEURONE FACTOR IN A HETEROZYGOUS 
CONDITION 
In 1921 aberrant color ratios appeared in a progeny of the cross 
Dh 416. This progeny was one of many that had been grown since 
the original cross was made in 1914, all being heterozygous for the 
C aleurone factor. The following season it was determined that the 
irregularities were due to another factor for aleurone color comple- 
mentary to C and located in another chromosome.. It now has been 
demonstrated that this is the factor B, which must have mutated 
from the dominant to the recessive condition. The bearing of this 
on the present study is that in two of the progenies used in studying 
the linkage relations of C and Wx there were plants heterozygous 
for B, giving back-crossed ears with 62.5 per cent white and selfed 
ears with 43.75 per cent white. The event has proved fortunate, 
since it has resulted in a demonstration that the presence of B in a 
heterozygous condition is associated with a lower crossing over 
between O and Wx, 
