BIOLOGICAL STUDIES OF FIGS. 907 



like long roots, which penetrate through the style, and 

 following its canal, finally through the funnel-shaped 

 opening in the ovule, reach the inner nucellus. The 

 fertilization has then taken place, and immediately after- 

 wards changes take place in the ovule and nucellus, which 

 in short time lead to the production of a fertile seed. As 

 a rule, we find that in the same flower the pollen grains 

 and the stigma are not fully developed at one and the 

 same time. It is therefore evident that the pollen in a 

 flower cannot be useful for fertilizing the stigma in the 

 same flower. This is nature's remedy against self-fertil- 

 ization, requiring that the pollen be brought from some 

 other flower or from some other tree of the same kind. 

 In the majority of flowers the pollen can only be trans- 

 ported from one flower to another by means of insects, 

 and often the flowers are so peculiarly constructed that 

 only a certain kind of insect can reach the pollen, or 

 rather, can reach the honey glands at the base of the 

 anthers, as without the presence of these glands the in- 

 sects would have no occasion to visit the flowers, which 

 in such a case would remain sterile. 



Nearly every flower we see in the field, and certainly 

 every bright colored flower, requires the visit of some in- 

 sect, in order that its stigma may be fertilized by the 

 pollen which adhered to the insect when it left the last 

 flower visited. Thus the insects and the flowers stand in 

 close intimacy. The honey glands of the flowers furnish 

 food for the insects, which are attracted to the flowers by 

 their size, color, scent, or by the odor of the honey. The 

 insects pay for their visit and for their meal by unknow- 

 ingly carrying the pollen from one flower to the other. 

 The insects are fed, the flowers pollinated. Only in 

 very few instances do the insects live and breed in the 

 flowers. One such instance is the fig, in which the 



