An account of a Botanical Expedition to 

 Lower Siam. 



It had long been clear that there was a very great differ- 

 ence between the flora of the Northern part of the Peninsula 

 South :of Burmah, and that of the southern portion from 

 Penang southwards, and it was in order to discover where the 

 boundary line between these two floras ; lay that I started 

 from Penang on the 23rd of February, 1910, for Alor Sta by 

 the little steamer Liuchiu. The boat started at 8 o'clock 

 a.m. and arrived at the town of Alor Sta at 2 p.m. Off the 

 island Pulau Bidan I noticed that the sea was for some dis- 

 tance of a bright green colour due to the immense abundance 

 of a minute green alga floating on the surface. The coast of 

 Kedah, where the river enters the sea, is extremely flat and low 

 lying, the Elephant hill, Gunong Geriang, and another one 

 standing out on the flat plain very conspicuously., The shores 

 were covered with immense quantity of Avicennia bushes and 

 trees. Avicennia officinalis usually occurs mixed up with the 

 true mangroves Rhizophoracnae but where-ihere is a demand 

 for firewood for steamers etc., unless protected the mangroves 

 are cut away so largely for firewood, piles and for fishing 

 stakes,fthat the valueless Avicennia often remains alone. Its 

 wood is not of use as firing and it seems to be considered 

 valueless for posts or stakes. A similar extensive area of 

 Avicennia to the exclusion of the Rhizophoraceae is to be seen 

 at Prai in Province Wellesley where the demand for mangrove 

 firewood has left the mud banks in possession of the despised 

 avicennia. The boat stopped a short time at a village at the 

 mouth of the river and then proceeded to the town an hours' 



Jour. S. B. R. A. Soc, No. 59, 191 1. 



