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disease also found on young African oil palms 
has been noted, the cause of which is obscure. 
In the early stages, from the first to the third year, 
the third leaf from the centre collapses at the base. 
This is followed gradually by the collapse of the 
outer leaves, so that finally only a single central leaf 
may be standing rigid. The youngest central leaves 
are left uninjured, and growth continues. Normal 
new leaves ajre developed, so that the final appearance 
is of a number of collapsed diseased leaves, below a 
normal development of rigid leaves. The growth of 
the tree is, perhaps, retarded for twelve months, 
but finally recovers. 
Diseases of Other Crops. 
During the last three years much attention has 
been given to the possibility of establishing agri- 
cultural industries, other than rubber and coconut 
cultivation, on an economic scale. The cultivation 
of the African oil palm is promising and the diseases 
so far encountered are similar to those of the coconut 
palm. Fibre plants of the Agave family have claimed 
considerable attention, but the leaves of these plants 
are generally strong and leathery, and do not 
form attractive feeding places for fungi. The plant 
Hibiscus Sabdariffa var. altissima, from which 
roselle fibre is obtained, appears very subject to 
eel- worm attacks. A bacterial disease, a wilt, and 
a die-back, are being investigated. 
Wither-tip, a ‘serious disease in the West Indies, 
has been observed on lime trees, which are now 
being cultivated on a plantation scale, but is causing 
little damage. A root disease, with symptoms 
similar to those shown in the case of rubber roots 
attacked by Ustulina zonata, has been under investi- 
gation. It is to be expected that the serious root 
