Another plant which performs an important function in the fertilisation of these arid formations, is the _Spinifex squarrosus_, the "water pink," as it is sometimes called by Europeans. The seeds of this plant are contained in a circular head, composed of a series of spine-like divisions, which radiate from the stalk in all directions, making the diameter of the whole about eight to nine inches. When the seeds are mature, and ready for dispersion, these heads become detached from the plant, and are carried by the wind with great velocity along the sands, over the surface of which they are impelled on their elastic spines. One of these balls may be followed by the eye for miles as it hurries along the level shore, dropping its seeds as it rolls, which speedily germinate and strike root where they fall. The globular heads are so buoyant as to float lightly on the water, and the uppermost spines acting as sails, they are thus carried across narrow estuaries to continue the process of embanking on newly-formed sand bars. Such an organisation irresistibly suggests the wonderful means ordained by Providence to spread this valuable plant along the barren beach to which no seed-devouring bird ever resorts; and even the unobservant natives, struck by its singular utility in resisting the encroachments of the sea, have recorded their admiration by conferring on it the name of _Maha-Rawana roewula_,--"the great beard of Rawana or Rama." The banks being thus ingeniously protected from the action of the air above, and of the water at their base, other herbaceous plants soon cover them in quick succession, and give the entire surface the first aspect of vegetation. A little retired above high water are to be found a species of _Aristolochia_[1], the Sayan[2], or _Choya_, the roots of which are the Indian Madder (in which, under the Dutch Government, some tribes in the Wanny paid their tribute); the gorgeous _Gloriosa superba_, the beautiful _Vistnu-karandi_[3] with its profusion of blue flowers, which remind one of the English "Forget-me-not," and the thickly-matted verdure of the _Hiramana-doetta_[4], so well adapted for imparting consistency to the soil. In the next stage low shrubs make their appearance, their seeds being drifted by the waves and wind, and taking ready root wherever they happen to rest. The foremost of these are the Scævolas[5] and Screw Pines[6], which grow luxuriantly within the actual wash of the tide, while behind them rises a dense growth of peculiar plants, each distinguished by the Singhalese by the prefix of "Moodu," to indicate its partiality for the sea.[7] [Footnote 1: _Aristolocia bracteata_. On the sands to the north of Ceylon there is also the _A. Indica_, which forms the food of the great red and white butterfly (_Papilio Hector_).]