FLORA OF THE SUNDRIBUNS. 
357 
9 
302. Oryza coarctata Roxb. ; F, I. ii. 206 ; F. B. 1. vii. 93. 
Everywhere in the forests on newly formed sloping alluvial river- 
banks, from the northern boundary to the sea-face, Hamilton^ Griffith ! 
Ellis ! Heinig ! Prain ! Sea-face, on sand covered by high tides, 
Prain ! 
! Vernac. Bani Dhdn, 
I A tall, rigid perennial grass, with wiry rootstock ; an excellent mud- and 
sand-binding plant. 
Distrib. — Sind. 
First discovered by Hamilton in 1796. This is the most common and most 
I plentiful grass in the Sundribuns ; it is the first species to establish itself on the 
" compensation banks of alluvium that are formed on the opposite bank of a rive^ 
whenever the * set * of the current produces erosion. Such banks vary in size from 
a few square yards to several acres ; wherever they occur there are closely and 
uniformly covered by a sheet of Oryza coarctata. Where the bank shelves 
rapidly off into deep water a narrow fringe of Myriostachya Wightiana is often 
associated with the Oryza at the river-edge ; the upper or forest margin of such 
a bank becomes at times invaded by a belt of Hargoza {Acanthus ilicifolius) 
bushes, and by young plants of Gengnsoa {Exccecaria Agallocha)^ Keora [Sonneratia 
apetala)i Bden {Avicennia officinalis) and the like. This belt of shrubbery 
I gradually extinguishes the Oryza coarctata. If such a belt, as sometimes happens, 
does not form immediately, a sward of Zoysia pungens, mingled with tufts of 
Fimbristylis ferruginea^ springs up instead on the landward side of the alluvial 
bank and drives the Oryza out. The plants of 0 . coarctata near the upper 
j edge of such a bank rarely exceed i8 inches in height ; towards the lower or river- 
edge they may be from 4 to 6 feet high. On the sand at the sea-face, the stems 
are only 4-8 inches high ; they are, however, perfectly healthy and flower 
profusely though they are covered by every high tide. The species is one of the 
best sand-binders on the coast, as well as the most effective of the mud binders 
j on these newly formed alluvial banks. 
j 333. Leersia Sw. 
303. Leersia hexaiidra Sw. ; F. B. I. 94. L. ciliata F. I. ii. 
207. E. D. L 247. 
' Northern clearings, in ponds, Calcutta Garden Collectors ! 
A floating grass ; a good fodder. 
Distrib. — Cosmopolitan in the Tropics. 
333. Zoysia Willd. 
304. Zoysia pung’eilS Willd. ; F. B. I. vii. 99. Agrostis matrella 
F. I. i. 317. 
Northern clearings, very common ; occasionally also in narrow 
patches behind alluvial river-banks throughout the forests; sea-face, 
common. 
j A wiry grass ; useless as fodder; an excellent sand-binder. 
