IN BORNEAN FORESTS [chap. 



a climate, the ataps are bad conductors of heat, so that houses 

 roofed with them are much cooler than those covered with ordinary 

 tiles or with wooden boards. I had learnt by experience that in 

 Sarawak it is not always easy to get what one wants, and especially 

 at the time one wants it, so I resolved to get my own men to 

 make the ataps I needed. 



After my first excursion to Mattang I had heard from the 

 Chinese that, in addition to the track across the forest by Siul, 

 there was a far easier route by water leading to the very foot of 

 the mountain. Several rivulets find their way down the north 

 side of Mattang, and, widening on the plain, form an intricate 

 system of canals which are under the influence of the tide. I was 

 told that, following at high-tide a small water-passage, or " trusan," 

 it was easy to travel by boat from the Sarawak river to the foot of 

 the mountain without having to go round by sea. 



Accordingly, in the beginning of January, I started up this 

 trusan with my men, and entered the Mattang channels. We 

 stayed here for about ten days, at a place called Salak, where 

 nipa palms grew in abundance, so that my men had every facility 

 for making the ataps I required. During the excursions I made 

 all round I had ample opportunities of investigating the peculiar 

 vegetation along the streams and estuaries which are influenced 

 by the tide. 



Descending the Sarawak river, just below Kuching, the " kayu 

 p'dada," or " peddada " of the Malays (Sonneratia lanceolata, Bl.), 

 abounds, a mere variety of 5. acida, which is not, however, strictly 

 an estuarine plant, for it thrives also in places where sea and fresh 

 water do not mix. 1 Together with the Sonneratia, but usually 

 farther away from the water, the predominant trees on the lower 

 Sarawak are Heritiera litoralis and three species of Brownlowia. 2 

 On the banks of the river Acanthus ilicifolius, with glossy and 

 spinose leaves, is about the only herbaceous plant which grows. 

 The true ligneous salt-water plants on the Sarawak river are about 

 ten species ; amongst these are Skyphiphora hydrophyllacea, 



1 In Celebes, at Kandari, on the banks of the Lepo Lepo river, where 

 Sonneratia acida, or a nearly allied variety, is common, I have observed that 

 during heavy rain the leaves change their position, and from the usual hori- 

 zontal take a vertical direction. The flowers are nocturnal, but are open 

 morning and evening, and are then frequented by various sunbirds (Nec- 

 tariniida?). 



2 These are Brownlowia sarawakensis, Pierre ; B. Beccarii, Pierre ; and 

 a third species yet unnamed. All these have the under surface of their 

 leaves silvery, such as botanists call " lepidote," i.e.. covered with minute 

 scales. Heritiera litoralis has similar leaves, whilst in A vicennia the under 

 surface of the leaves is covered with a thick white woolly coat. Considering 

 the small number of trees which grow along the river near the sea, to find 

 amongst them five species with lepidote leaves suggests the idea that local 

 biological circumstances render this peculiarity advantageous. 



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