The river-banks are lined with nipa palms and mangroves. At low tide you can see the mangroves, standing on trestles of black woody roots, looking like snakes writhing in the mud. Upon these pedestals, a crown of bright green leaves, thirty to forty feet in height, form aquatic forests at the mouth of the rivers all along the coast. Each branch is weighed down by a fruit, which, when ripe, drops into the mud and starts a new tree. The nipa palm has matted roots which easily retain the flotsam and jetsam carried down by the unceasing current of the waters; it has an angular fruit which, like that of the mangrove, sinks into the mud and forms forests on its own account. The incessant action of these encroaching trees add continually to the land. Indeed, there are certain aged natives who have been heard to say that part of the coast near Sirik, although exposed to the constant surf of the north-east monsoon, has encroached on the sea for two miles or more, during their lifetime. When the land reclaimed by the mangroves and nipa palms becomes dryer, the trees die, and give place to other tropical vegetation. On my travels in and out of these rivers, I have often seen, especially on a hot sunny day, the distant line of coast just before it recedes into the horizon, looking as though it were lifted high up in the air, when, between the line of verdure and the sea, appeared a space of light as though the trees stood on rays of silvery transparency. [Illustration: DATU BAY NEAR SANTUBONG] The rivers Lundu, Sarawak, Sadong, Batang Lupar, Saribas, Kalaka, and Rejang flow into the Bay of Sarawak. The rivers Oya and Muka (from which two rivers an important trade with sago is carried on), Bintulu and Baram, are situated in the more northern portion of the territory. Owing to the perpetual strife between land and water, these rivers have bars at their mouths, but the bar across the Baram is the most formidable amongst the rivers of the country.