178 GLIMPSES IXTO I'LAXT-IJFE 



pollination, fertilisation, and the growth of the 

 ovule. There is so much to be said about the 

 first subject, that I must leave the two latter for 

 a succeeding chapter. 



Before seed can be formed it is necessary that 

 the powder contained in the anthers, which is 

 called pollen, should be transferred from those 

 anthers to the stigma or upper part of the pistil, 

 and this transference is called pollination. If we 

 examine a tulip or, better still, a buttercup, we 

 find the anthers and stigmas so near together 

 that the transfer of the dust-like jjt^Uen to the 

 sticky- looking stigmas can easily take place. 

 This \\-ould be called an instance of self- 

 pollination, but although cases of this kind do 

 occur in nature, they are not at all common. 

 As a rule, in order to ensure what is called 

 cross-pollination, the transfer of the pollen of one 

 flower to the stigma of another, many wonderful 

 and interesting arrangements exist even in some 

 of our commonest flowers. 



Cross-pollination must be the case in such plants 

 as dog's mercury, because we find in a colony of 

 these plants — so frequently seen by the roadside — 



