10 MALAYAN FISHES. 
Within the writer's memory the main rivers of the West coast 
were fine clear streams. The waters provided irrigation for the 
rice fields and contained quantities of fine edible fish. These rivers 
are now thick turbid streams carrying a heavy burden of slime and 
silt. 
We have probably one hundred different species of, Carp alone, 
besides dozens of species of Catfish and many fine fish belonging to 
the families OSPHROMENIDAE, NOTOPTERIDAR, etc., ete. Catfish can 
exist in slime and silt though it is questionable whether they can 
thrive, but Carp certainly require clear water to breed in. 
One of our Carp the Kélah (Barbus sp.) has been described 
by Swettenham as the finest fresh water fish he ever ate in the East, 
and the Kalui (Osphromenus olfax) is so highly esteemed that 
several attempts have been made to introduce it into France, and it 
has been acclimatised in Mauritius, Australia and parts of India. 
Tin mining is necessary and some pollution of the rivers is 
unavoidable, but there have been many cases where carelessly con- 
structed dams have broken and a turbid flood of slime has been 
allowed to pour direct into the rivers for months while leisurely 
Tepairs are being made. Though much of the damage done in the 
past is irremediable, let us hope that a more general ‘recognition of 
the value of the fresh water fisheries will result in a fair measure 
of protection in the future. There are still rivers which can be 
saved. 
By saving our fresh water fisheries we shall save, incidentally, 
our rice-fields, for Rice and Fish in addition to being the two 
staple foods of the country are inseparable. When you destroy one 
you destroy the other. 
Where you can grow rice you can catch fish and where you can 
no longer catch fish you cannot grow rice. 
To explain: the mining silt which pours into the rivers gradual- 
ly raises the bed of the stream and so causes a rise in the water 
table. A rise in the water table limits the area of drainable land, 
and drainage is as necessary to a rice field as irrigation. So the 
area which can be planted with rice becomes smaller and smaller 
until eventually the water table is so high that the river channel 
can no longer carry off storm water. The resultant floods deposit 
a layer of slime and silt on the rice fields and complete the work of 
destruction. 
Fish cannot breed in the rivers polluted with slime and silt, 
so the Fisheries and rice fields perish simultaneously. In our 
policy of construction and development these facts should not be 
lost sight of. 
There is yet another point which has received no attention and 
that concerns anadromous Marine fishes which enter rivers to 
spawn. Among these fishes the principal one is the Shad (Téru- 
