18 
BULLETIN 61, HAWAII EXPERIMENT STATION 
two examples in fruit variations indicate that color, flavor, and odor 
characters are to some extent hereditary. The papaya, like various 
other kinds of plants, has mutating characters which reoccur and 
predominate rather unexpectedly. The orange-fleshed fruit contains 
red pigments which occasionally develop in multiple form, and give 
the red color in place 
of the orange. 
SEX DETERMI- 
NATION AND IR- 
REGULARITIES 
The problem of sex 
determination in the 
papaya has led to 
considerable specula - 
tio n. For some 
years claims have 
been made that the 
sex of the future 
plants can be deter- 
mined before the ap- 
pearance of the blos- 
soms. In many in- 
stances it has been 
stated that pistillate 
plants develop from 
seeds taken from cer- 
tain portions of the 
cavity of the fruit. 
Occasionally it is re- 
ported that fresh 
seeds producing pis- 
tillate flowers can be 
accurately separated 
by their appearance 
from those producing 
plants with stami- 
nate flowers, and, like- 
wise, that pistillate 
plants can be success- 
fully identified dur- 
ing the first few 
weeks of their growth 
previous to being 
set in permanent 
place. Investigations were made at the station to determine 
whether this was true. In one experiment, carried on from 1922 
to 1924, 72 plants were grown from seeds of one oblong pa- 
paya, 36 of the seeds being from the portions of the cavity at the 
basal or stem end, and the rest from toward the stigmatic end of 
the cavity. The seeds of each section gave a large percentage of 
pistillate plants, but no evidence was obtained to show that the seeds 
Figure 16. — Crowded and dwarfed fruit and constricted 
trunk growth resulting from prolonged drought 
