1865.] The Vegetation of the Islands of the Indus River. 59 



S. spontaneum has sprung up, and its leaves now aid in catching the 

 seeds of the Tamarix and S. 3Iunja, which having ripened, are flying 

 about at the mercy of the winds. The two latter lie dormant until 

 the next year. In the meanwhile the 8. spontaneum for a short time 

 kept down by the cold season and eaten over by the cattle, has its 

 growth stopped until March or April, when it springs up, and by 

 September is in its full growth and blossom. The Tamarix and S. 

 Munja being now, on the rising of the river in August, placed under 

 favourable circumstances, begin to grow rapidly, and by the end of the 

 second year cover the Balaa, killing out S. spontaneum to a great 

 degree. Upon the island being flooded at the end of the second year, 

 the vegetation on it catches the seeds floated down by the river, and 

 these in their turn germinate and gradually develope a jungle. At 

 very little expense, indeed, many of these Balaas might be sown 

 broadcast with the seeds of timber trees, (Acacia or ' Sissoo' are 

 undoubtedly the best) about the beginning of August. When the river 

 rose it would cover the islands and deposit sufficient alluvial soil to 

 permit their germinating and taking root. The seeds would not be 

 •carried off by the currents, as they become entangled in the grass, 

 which after an inundation is generally seen pressed flat to the surface ■ 

 with a large amount of alluvial deposit keeping it down. 



Developing jungles on these islands, would not only supply timber, 

 firewood, &c, but by making the islands permanent, would to a 

 great extent assist in forming a permanent channel for the river, the 

 absence of which is one of the great difficulties to be overcome at 

 present by the navigator. 



