CHARACTERS IX AX UPLAND-EGYPTIAN" COTTON HYBPJD. 
21 
Fiber character, range of length, Plate X, € and D. 
Seed character , range of fuzziness, Plate XI, C and D. 
MENDELIAN SEGREGATION IN THE HOLDON-PIMA HYBRID. 
The only characters which showed a markedly bimodal distribution 
in F 2 are petal spot (fig. 27; . anther color (fig. 29), and midlock 
so 
s-o 
+o 
*■ J- a- r <3 & 
i 
i 
L 
~c 
9 
f 
\ 
f 
\ 
y 
f 
/Vf/VO r/9/e/rfT/O/Vj f> f/ZO J*9/Z//97-/0/tf 
eo 
30 
20 
/o 
/ -? y 
S £ r <3 & 
1 
%. 
/ 
k>' 
/ 
1 
v^ 
// 
■/ 
N 
V 
S 
r 
\ 
Fig. 23.— Calyx gland abundance: Frequency dis- 
tribution of Holdon x Pima F2 cotton plants, by 
grades, as used in computing the correlations. 
The ordinate figures indicate the number of 
plants as a percentage of the tocal population. 
Fig. 24.— Corolla length: Frequency distribution 
of Holdon X Pima F2 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. 
furrow index (fig. 37;. Faint indications of bimodality are also to 
be noted in the curves for leaf index (fig. 10) and bract connation 
index (fig. 18), but these are almost certainly not significant. Evi- 
dence of Mendelian segregation in petal spot was afforded by data 
from both F 2 and F 3 . Anther color and midlock furrow index, 
unfortunately, were not determined on the V ? populations, but a 
Fig. 2.5.— Corolla index: Frequency distribution of 
Holdon X Pima F 2 cotton plant 
in computing the correlations. The' ordinate figures 
indicate the number of plants as a percentage of the 
total population. 
ffOr 
s-o\ 
*?o 
/ 
v 
i 
L 
\ - 
^ 
9 
S 
v 
/ 
\ 
1 
> 
L 
=> 
I 
N 
/y (//o s<4je//9r/owJ /=> (Wo w?#//?t/o/v) 
Fig. -o.— Petal color : Frequency distribution of 
Holdon X Pima Fj cotton plants. 
I in computing the correi i1 
nate figures 
percentage of the total population. 
strong presumption of Mendelian segregation is afforded by the 
frequency distributions in F 2 . 
PETAL SPOT. 
On the basis of the entire F 2 population (215 the 
actual distribution for this character and 
