WHITE AND GREENISH FLOWERS 



Water- PI an tain 



{Alisma Plantago-aquatica) Water-plantain family 



Floivers — Very small and numerous, white, or pale pink, whorled 

 in bracted clusters forming a large, loose panicle 6 to 15 in. 

 long on a usually solitary scape y 2 to 3 ft. high. Calyx of 3 

 sepals ; corolla of 3 deciduous petals ; 6 or more stamens ; 

 many carpels in a ring on a small flat receptacle. Leaves: 

 Erect or floating, oblong or ovate, with several ribs, or lance- 

 shaped or grass-like, petioled, all from root. 



Per/erred Habitat — Shallow water, mud, marshes. 



Flowering Season — June— September. 



Distribution — North America, Europe, Asia. 



Unlike its far more showy, decorative cousin the arrow-head, 

 this wee-blossomed plant, whose misty white panicles rise with 

 compensating generosity the world around, bears only perfect, 

 regular flowers. Twelve infinitesimal drops of nectar, secreted in 

 a fleshy ring around the centre, are eagerly sought by flies. As 

 the anthers point obliquely outward and away from the stigmas, 

 an incoming fly, bearing pollen on his under side usually alights 

 in the centre, and leaves some of the vitalizing dust just where it is 

 most needed. But a " fly starting from a petal," says Muller. 

 "usually applies its tongue to the nectar-drops one by one, and 

 after each it strokes an anther with its labellie ; in so doing it may 

 bring various parts of its body in contact with the anthers. As a 

 rule, however, the parts which come in contact with the anthers 

 are not those which come in contact with the stigmas in the same 

 flower." Any plant that lives in shallow water, which may dry 

 up as summer advances, is under special necessity to produce an 

 extra quantity of cross-fertilized seed to guard against extinction 

 during drought. For the same reason it bears several kinds of 

 leaves adapted to its environment : broad ones that spread their 

 surfaces to the sunshine, and long grass-like ones to glide through 

 currents of water that would tear those of any other shape (see p. 

 155). What diversity of leaf-form and structure we meet daily, 

 and yet how very little does the wisest man of science understand 

 of the reasons underlying such marvellous adaptability ! 



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