CHARACTERS IN AN UPLAND-EGYPTIAN COTTON HYBRID. 
25 
the spot. It should be noted, however, that the whole of progeny 161 
and part of progeny 123, including the individual showing presence of 
the spot, were grown from open-pollinated seed. While all the plants 
which were graded in these two progenies were judged from their 
general appearance to have originated from self-fertilized ovules, 
the possibility exists that the individual in each of these progenies 
/o 
fa?/ 
E" 
til 
V- 
^ 
/ 
/ 
Fig. 37.— Midlock furrow index: Frequency dis- 
tribution of Holdon X Pima F2 cotton plants, 
by grades, as used in computing the correla- 
tions. The ordinate figures indicate the num- 
ber of plants as a percentage of the total popu- 
lation. 
/o 
/ .«? 3 ■** ^ £■ P- <S & 
W" 
s=; 
.V 
/* 
-/=> 
Fig. 38.— Fiber length: Frequency distribution 
of Holdon x Pima F 2 cotton plants, by grades, 
as used in computing the correlations. The 
ordinate figures indicate the number of plants 
as a percentage of the total population. 
which showed presence of the spot may have resulted from cross- 
fertilization. 18 
It is interesting that there were two entirely spotless F 3 progenies 
(Nos. 19 and 171) the F 2 parents of which had been recorded as 
showing presence of the spot. The mere trace (grade 1) recorded for 
F 2 plant No. 19 may have been due to mistaking discoloration due to 
an extraneous cause for presence of the red pigment, but this could 
30 
/o 
/ ^ 3 
<3 -P 
1 
-\ 
y 
/ 
/ 
/> 
/=> 
/y (fro w/e/spT/on) ■ 
GO 
JO 
/o 
/=, 
X 
A 
> 
8 
¥ 
v// 
-/y 
Fig. 40.— Lint index: Frequency distribution of 
Holdon X Pima Fa cotton plants, by grades, 
as used in computing the correlations. The 
ordinate figures indicate the number of plants 
as a percentage of the total population. 
Fig. 39.— Fiber color: Frequency distribution of 
Holdon x Pima Fg cotton plants, by grades, as 
used in computing the correlations. The ordi- 
nate figures indicate the number of plants as a 
percentage of the total population. 
not well have been the case with F 2 plant No. 171, which was 
graded No. 3. 
Only two of the F s progenies, Nos. 44 and 29, appeared to be 
homozygous for presence of the spot. In all the other progenies one 
'8 This was probablv the case with the plant in progeny 123 whieh was graded No. 5 in pes] i 
petal spot, this individual having been decidedly aberrant in respect to leat in [ex and vein angle also. 
42433—23 4 
