FRUCTIFICATION OF FLOWERS. 83 



occurrence in stagnant waters. Thus buoyed up, the blossom 

 rises to the surface, and expands its large yellow petals in the 

 atmosphere, but as soon as fructification is accomplished, the air 

 of the bladders escapes or is absorbed, and the sinking Utricularia 

 returns to its more congenial element. In other cases, where 

 the depth of the water in which it grows is too great to allow 

 the plant to rise to the surface, as, for instance, in many species 

 of Water-wort (Elatine), and Water-plantain (Alisma), a bubble 

 of air is secreted within the folded corolla at the time when 

 fructification is to take place, and forms a subaqueous atmo- 

 spheric chamber in which the process can be safely accom- 

 plished. 



But the fructification of the Vallisneria spiralis, a common 

 plant in the ditches of the rice-fields in Italy, is beyond all 

 others curious. This herb grows in the mud, generally several 

 feet below the surface of the water, and has its stamens and 

 pistils on different flowers. The anthered flowers grow in short- 

 stemmed compact knobs at the basis of the leaves, while the 

 stigmate-flowers are seated on long stalks spirally contracted 

 like a corkscrew. When the time of fructification approaches, 

 the small anthered flowers detach themselves from their stalks, 

 and swim about upon the surface, where they freely emit their 

 snow-white pollen ; w r hile the stigmate flowers, in which a 

 similar separation from the maternal plant was not admissible, 

 gradually rise to the top by the unfolding of their spiral coils. 

 As if prompted by an animal instinct, they are constantly 

 moving on the surface, as though they were seeking the small 

 anthered flowers, which are at the same time swimming about 

 in considerable quantities. When fructification is completed, 

 their long stalk again contracts into a spiral, and the flower, 

 having no longer the contact of the water to fear, sinks again 

 to the bottom, where the fecundated germ grows to maturity. 



Thus a despised and troublesome weed shows us wonders in 

 its organisation, which would be utterly incomprehensible if we 

 did not attribute them to a divine and all- wise Creator ! 



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