50 
SPICES 
CHAP. 
The stigma, being very sticky, retains the pollen and 
withdraws it from the stick ; the rostellum then released 
flies back to its original position and helps to press the 
pollen into the stigma. 
Another method sometimes used is to employ a thin 
flat stick and to press the rostellum upwards beneath 
the anther cup, pressing this with the thumb so as 
Vanilla Fertilisation. 
A. Column from in front. 
B. Side view. 
C. Side view showing position of fertilising 
stick. 
D. Rostellum pushed up and pollen touching 
stigma. I 
E. Side view of column showing attachment 
to lip. 
a. Anther. 
p. Pollen. 
r. Rostellum. 
s. Stigma. 
to slide it over the rostellum, and force the pollen into 
the stigma. This method, however, is not so satisfactory 
as the first one. It is rougher and perhaps easier to 
effect, but there is a certain amount of uncertainty as 
to whether the pollen has quite reached the stigma and 
is well inside. 
By both these methods the pollen of a flower is used 
to fertilise its own stigma. It is probable that better 
results would be obtained by transferring the pollen of 
