450 



HUTCHINSON'S POPULAR BOTANY 



plant lifts its head above the marsh or salt-pool which it inhabits. Lengthen- 

 ing continues until the object is attained, but thereupon ceases, no matter 

 what the depth or shallowness of the water. The Rev. Gerard E. Smith. 

 a botanist well acquainted with the plant, has thus sketched the process : 

 " The anthers are vesicular and buoyant : as they swell and become mature, 

 the membranous sheath enclosing them is distended, and the whole is 



brought to the sur- 

 face of the water. 

 The flower-stalks are 

 rapidly lengthened, 

 the flowers quit the 

 sheath, which then 

 becomes a bladder, 

 and aids the eleva- 

 tion of the spike an 

 inch above the 

 water. Presentl}* 

 the anthers burst, 

 the vesicle loses its- 

 buoyancy, and the 

 flower-stalks, bear- 

 ing the fertilized 

 stigma, sinks within 

 the bosom of the 

 parent plant." It 

 will be noticed that 

 the flowers both of 

 Tassel-grass and 

 Zostera are small 

 and inconspicuous,, 

 and possess neither 

 calyx nor corolla. 

 Large blossoms and 



Photo by-} [E. step. bright colours would 



FIG. 554. SCOTS PINE (Pinus sylvestris). be useless to plants 



which depend on 

 water for the distri- 

 bution of their pollen, just as they are to the wind-pollinated forest trees. 

 Doubtless the most curious of hydrophilous plants is the Italian Eel-grass 

 (Vallisneria spiralis), which is also one of the greatest marvels of the 

 vegetable world. It is distributed throughout Southern Europe, and grows 

 in still water. Our illustration (fig. 515) shows both the male and female 

 plants, with their strap-shaped leaves and flowers in various stages ; the male 

 plant is on the right, the female on the left. The pistillate (i.e. female) 



The female flowers are 



ienal; the tips of the shoots. The cones are soon formed, but 

 seeds do not ripen until the second year. 



