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opposite them serving asa guide. The tube of the corolla is about 
as long as the ovary. The style and ovary are green. The 
anthers are introrse and adnate, though the point of attachment 
to the filament is a little above their base, making them slightly 
versatile, so far at least as to turn back with facility. At the time 
of bursting they bend back, becoming arcuate in shape and 
open upward. When an insect lights upon a flower and turns 
about in the effort to reach the various nectaries, these anthers 
are favorably situated to leave the pollen on its uncer side. The 
stigmas of the flower being closed on one another are not yet in 
a condition to receive this pollen, except a small quantity which may 
be left on the few hairs that project from the edges of the cleft. 
But when an older flower is subsequently visited, it will have its 
stigmas turned in the proper way for the reception.of the grains. 
Working about the flower to obtain the nectar, all parts of the 
exposed stigmas are likely to come in contact with some part of 
the insect to which pollen adheres, and the grandular stigmatic 
hairs will rub it off and hold it. In this way cross-fertilization 
will be effectually secured. 
The structure and mode of bursting of the anthers is an 
additional help in this process. By curving they are made stiff, 
and their walls are stretched. The tissue of the cell-walls is very 
elastic. While experimenting with the anthers to see how they 
opened, one was pressed along its sides between the prongs of a 
_ pair of forceps. The instrument suddenly slipped, and the shock, 
or relief from pressure, was so great that the cells burst, quickly 
throwing out the pollen to quite a distance. Repeating the 
experiment and imitating the first operation as nearly as possible, 
others were ruptured in the same manner. Sometimes the elastic 
force was so great as to nearly empty the cells by a single effort. 
Doutless an insect will also exert a like pressure, by grasping the 
anthers with its feet or pressing them between its legs while at 
work upon the flower, and cause their bursting in a similar way. 
As a result the pollen will be shot against its body, and more 
adequately dust it than by a simple act of rubbing against them. 
The tissues of the cells being stretched and the anthers bent’ into 
the form of a bow, as soon as they are unloosed, shoot out their 
tiny missiles, stored up within, and hit their insect guests, not as 
enemies, but as agents of the plant in furthering its economy. 
