135 
FUNGI FROM PENANG; FROM Mr. FOX, 6—1—10. 
Nos. 4, 5, 7 and 9. Polyst ictus occidentalism Fries. 
No. 6. Polystictus florid anus, Berk. 
No. 8. Schizophyllum commune, Fries. 
Polystictus occidentals is the only parasitic species, and but little is 
known respecting its life-history, but judging from analogy its 
diffusion can be affected by wind borne spores or by underground 
mycelium spreading from one tree to another. As the trees are so 
large and presumably old, the question arises as to whether they have 
not passed their prime, and are becoming too weak to supply the 
required amount of water and food to the branches. If a trench 
could be formed around the base of the trunk, and flooded with a 
solution of nitrate of potash or nitrate of soda (preferably the first 
named), using one pound to three gallons of water, say once a week, 
for two months, the end would be somewhat delayed, but no cure 
is known. 
(Signed) G. Massee. 
t8 — 1 — 10. 
RUBBER AND ITS SUBSTITUTES. 
The circular which was issued recently by the Synthetic Rubber 
Co. announcing the proposed voluntary winding-up, on the grounds 
that further expenditure was not justified, has given great satisfaction 
to dealers and brokers in rubber, although it may be said that in 
Mincing Lane the synthetic bogey never caused much apprehension, 
even though Professor Dunstan, at the British Association Meeting 
in I906, confidently predicted the synthetic production of rubber 
before the Association met again at York. At present there is still 
no likelihood of the prophecy coming true, but the commercial pro- 
duction is by no means an impossibility. It is interesting from this 
point of view to give a resume of the many attempts, especially 
during the last decade, to make artificial rubber or prepare satisfact- 
ory substitutes for it. The only known actual synthesis of caout- 
chouc is that accomplished by Bouchardet and Tilden by polymeri- 
sing isoprene (CH : (CH2). (CH2) CH), which is itself one of the 
distillation-products of caoutchouc. Wallach and Tilden (1892) also 
showed that isoprene obtained from turpentine behaves similarly to 
that obtained in the destructive distillation of rubber. Kondakow, 
in 1902, prepared a substance closely resembling caoutchouc, by the 
action of light for a year on di-iso-propenyl or methyl isoprene. A 
British patent granted in 1907 proposes to convert acetelene and 
ethylene into di-vinyl under the influence of a dull red heat, which 
latter product yields' methyl di-vinyl or isoprene on treatment with 
methyl chloride. The isoprene is then to be condensed to rubber. 
Other processes have been patented on the assumption that coal tar 
■! contains polymers of isoprene or compounds convertible into such 
substances. Thus Seguin and Boussy de Sales patented in France 
Y during 1903, a process according to which tar (containing isomers of 
