AND CROSS-FERTILIZE THEIR FLOWERS. 
35 
69. One might doubt whether such movements as those of the stamens of Bar- 
berry and of Kalmia were really intended for the use here assigned to them. 
But they serve this purpose, unquestionably, and we can think of no other. Now 
there is a flower of a tropical Orchid, cultivated in some conservatories (named t 
Catasetum), in which a movement under irritation (analogous to that of the Bar- 
berry-stamen) and one of elasticity (like that of Kalmia) are combined in one 
apparatus, — one so elaborate and special that nobody can doubt that it is a con- 
trivance for this particular purpose. It cannot well be described here without 
numerous figures and much detail. But the amount of it is, that a sensitiveness 
of two slender and partly crossed arms, which the moth or other large insect must 
hit in reaching the flower-cup, liberates a pollen-mass which is set as a spring, and 
lets it fly like a catapidt ; it hits the head of the insect at some distance, disk-end 
foremost, and sticks fast to it, in proper position to be applied to the stigma of the 
next proper flower visited. 
70. Returning to flowers of ordinary structure, and of familiar kinds, two par- 
ticular arrangements for insuring cross-fertilization in perfect flowers must be 
briefly noticed. The commonest is that of 
71. Dichogamous Flowers. Dichogamy is the name given to the case in which 
the stamens and the stigmas of the same blossom come to perfection at different 
periods. That is, the anthers mature and discharge their pollen in some plants 
before the stigma is ready to receive it, in others only after the stigma has with- 
ered. Either way, the pollen that fertilizes and the stigma that is fertilized can 
never belong to the same blossom. 
72. In the Common Plantain of our dooryards and waysides, Plantago major , and 
in the English Plantain, or Ripple Grass ( P . lanceolata) of the fields, this is famil- 
iarly illustrated. The style projects from the apex of the closed bud, ready to 
receive pollen from other flowers a day or two before its stamens are hung out 
upon their slender filaments, to furnish pollen for other flowers, — not for their 
own, the stigma of which is by that time dried up. Plantain-flowers, however, 
produce no nectar, and are neither fragrant nor brightly colored ; so they are not 
visited by insects, but are left to the chance of the conveyance of the pollen by 
the wind. It is the same with many Grasses and Grains, only in reverse order. 
Their anthers hang out on their slender filaments one morning, and the feathery 
stigmas of that blossom not until the next morning ; and the wind is the pollen- 
carrier. 
