FORMATION OF SEED. 



I2 9 



Now in due course some of the pollen grains of the 

 stamen will be brought to the stigma of the pistil. 

 There they will stick fast, being held by a kind of 

 sticky fluid which is formed upon the stigma. Try if 

 you can see through your magnifying glass any 

 pollen grains upon an}' 

 of the stigmas of the 

 flowers which you have 

 gathered. If not, look 

 for a large flower that 

 has begun to fade, 

 and try again. In the 

 little violet even you 

 should see through a 

 good glass the little 

 mouth or opening of 

 the channel down the 



Stigma and perhaps also Fig. 109. Diagram of a flower. A>, 

 , , ... calyx ; K. corolla : /. filament ; a, 



some pollen sticking anther with pollen bags open sho wing 

 round it. This settling P llen P ain * { ^ ; "* the sti f ma; * 



& the style ; F, the ovary ; z, the inner 



of the pollen upon the covering of the ovule, S ; em, inner 



bag containing the vital part of the 



stigma is called polli- ovule, at E. 



nation. 



But it is not always so good for a flower for pollina- 

 tion to take place by its own pollen as by that of 

 another flower. Indeed this is sometimes necessary ; 

 for, as we have seen, the stamens and pistil are some- 

 times removed from one another by being in separate 

 flowers (monsecious, p. 123), or in separate plants 

 (diaecious, p. 123); and, in flowers in which stamens 

 10 



