CUAP. I.] SAND FORMATION. 49 



tion in the fertilisation of these arid formations, is the 

 Spinifex squarrosus, the " water pink," as it is sometimes 

 called by Europeans. Its seeds 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, 

 the heads become detached from the plant, and are 

 carried by tke 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. 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 estua- 

 ries 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 seed-devouring birds seldom resort. Even 

 the unobservant natives, struck by its singular utility 

 in resisting the encroachments of the sea, have re- 

 corded their admiration by conferring on it the name of 

 Maha-Rawana rcewula, " the great beard of Eawana." 1 

 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 suc- 

 cession, and give the entire surface the first carpet of 

 vegetation. A little retired above high water are to be 

 found a species of Aristolochia 2 , the Sayan 3 , or Choya, 



1 See the story of Rama, Vol. I. p. 

 678. 



2 Aristolochia bracteata. On the 

 sands to the north of Ceylon there is 

 also the A. Indica, which forms the 

 food of the great black and red but- 

 terfly (Papillo Hector). 



VOL. I. E 



3 Hedyotis umbettata. A very cu- 

 rious account of the Dutch policy in 

 relation to Choya dye will be found in 

 a paper On the Vegetable Produc- 

 tions of Ceylon, by W. C. ONDAATJIE, 

 in the Ceylon Calendar for 1853. 

 See also BEBTOLACCI, B. iii. p. 270. 



