90 SCHOOL AND HOME GARDENS 
Cross-pollination. Petunias afford interesting material 
for experiments in cross-pollination. Plant two varie- 
ties of petunias, preferably pure white and red-purple. 
When the corolla is about to open, cut away a part 
of it and remove the stamens (as indicated in Fig. 49) 
and tie a paper bag over it. At the same time place a 
bag over another one that has not 
been opened. In a day or two, 
when the flowers open, remove 
the bags and with a small brush 
transfer pollen from the flower 
that contains stamens to the pistil 
u ¢ of the one that has the stamens 
removed. Replace the bag over 
the one that has been fertilized, 
to let the seeds ripen. Transfer 
len fr hi paial 
ealin estes pollen from white to red-purple 
Tote eee flowers and from red-purple to 
part of the corolla opened, yhite. Continue sowing seeds from 
showing stamens and pistil ; . 
c, same, with top of stamens the cross-pollinated plants for sev- 
removed 
eral seasons, and make a note of 
the number of red-purple, of white, and of any mixed 
colors that you obtain. Seeds gathered from red-purple 
and from white flowers should be sown separately. 
The plants that are to yield seed should be kept sepa- 
rate, to prevent further cross-pollination. If you produce 
plants that bear unusually fine flowers, reproduce them 
by means of cuttings. 
