66 TlMEHRI. 
which is being worked out at Kew. 
Other plants are known to yield caoutchouc, but mostly 
in insufficient quantity, or of too poor a quality to make 
its collection remunerative. 
As I have already said, gutta-percha is produced by 
two species of Sapotacex, Isonandra gutta and Mimu- 
sops balata. That of the latter is the well known balata 
gum of this colony. 
Isonandra gutia is a large tree found, like Urceola 
e/astica, on the Malayan peninsula in Singapore. It grows 
to a height of eighty feet, the trunk being three feet or 
more in diameter. Another less well-known species of 
this genus affords some gutta-percha. 
Mimusops balata — the balata or bully tree of Guiana 
— is next in importance, it is found in British, French, 
and Dutch Guiana : and either this or very closely allied 
plants are also found in Venezuela, Trinidad, and Jamaica. 
On points of the Berbice, Canje, and Mahaicony rivers 
of Guiana it is particularly plentiful. It is one of the 
finest forest trees of the country, eighty feet high or more, 
having a trunk two feet in diameter. The wood is hard 
and very durable. Two kinds are recognised by the 
balata collectors and woodcutters, which from their des- 
cription are either well marked varieties or distinct spe- 
cies — a question it would be very interesting to determine. 
The first exportation of balata gum took place more 
than twenty years ago, when a small sample was send 
home for expirement. The quantity increased yearly, 
and in 1865 reached 20,000 lbs. In 1874 it fell to 1,669 
lbs., which fetched £111 in the market. The next year 
the figures were 10,134 lbs., realizing only £1 14. 10. o. 
