42 
C. papaya has been hybridized with C. gracilis, the latter as the male 
parent. In the orchards of the Hawaii station there are trees which 
are believed to be natural hybrids of C. papaya and C. peltata. At- 
tempts made at this station to cross C. papaya with C. quercifolia 
have failed. 
AN ATTEMPT TO BREED A HERMAPHRODITE PAPAYA. 
Mr. John Scott, 1 who had observed plants apparently of the 
forbesii form but had not seen those of elongata or pentandria, was 
impressed with the idea that it would be possible to increase the num- 
ber of hermaphrodite flowers and shorten the peduncles until a truly 
hermaphrodite race would be attained. The work was begun but 
was unfortunately terminated by the early death of Mr. Scott. 
IDEALS IN BREEDING THE PAPAYA. 
There seems to be no good reason to doubt that it will be possible to 
breed a papaya combining at least many of the most desirable characters 
and to hold the variety reasonably stable by the same means as 
are employed in maintaining seed varieties of vegetables and garden 
flowers. This presupposes segregation or hand pollination in either 
case, the latter being the method which most breeders will be com- 
pelled to follow because of the proximity of other varieties over which 
they have no control. The simplicity of hand pollination in the 
papaya and the large number of seeds resulting from one operation 
renders it a very practical means even for commercial seed produc- 
tion. 
It may be well to outline here some of the ideals which the breeder 
should have in mind in his search for Mendelian characters which may 
be combined. 
1. Vigor of tree. — It is important with the papaya, as with other 
species, to use vigorous individuals as parent stocks. 
2. Early and low fruiting habits. — There is a wide variation in the 
plants in this respect, some producing no fruit on the first five or six 
feet of the stem, while others bear fruit which almost touches the soil. 
It is believed that this is a character which may be transmissible, and 
the advantage of early and low-bearing trees is obvious. 
3. Freedom from the branching habit. — Trees that produce side 
branches freely require considerable pruning to prevent the numerous 
new shoots from taking the nourishment which should go to the fruit. 
4. Productivity but not excessive bearing. — Trees that have long bare 
spaces on their stems and those whose fruits are so numerous as to 
crowd each other should be avoided in favor of such as have the fruits 
well spaced with just sufficient room to mature normally. 
i Trans. Bot. Soc. Edinburgh, If (1873), pp. 287-288. 
