PART IV.
At last it was noticed that in a few trees the inflorescences on one
side always aborted whilst those on the other side of the tree produced
good nuts; on examination it was found that the stem and many of
the petioles had been damaged by rhinoceros bettle on the side of the
bad nuts. After this a close search was made of a number of trees bearing
 diseased nuts or abortive inflorescences and it was found in nearly
all cases that petioles had been nibbled and holes eaten in the trunk.
Recently a tree which had borne an excellent record for both nuts and
inflorescences for the last 13 months was noticed to be deteriorating,
some of the young nuts were developing lesions, and a young
inflorescence dropped all its female flowers. When examined petioles
were found to have been eaten and there was much frass; though the
actual beetle was not found there was abundant evidence that the tree
had been damaged by rhinoceros beetle.
CONCLUSION.
It is suggested, that the evidence regarding nut fall and gummosis
in Zanzibar, though at present very incomplete, points to the lack of
nutrition as being the cause of the disease. This mal-nutrition may
be general, due to lack of food or water in the soil or to inactive roots,
the result of poor aeration of the soil. Or, it may be local and be due
to the cutting off of the food supply from the inflorescences, the result
of mechanical injury caused by the rhinoceros beetle.
There is evidence that our Zanzibar coconuts are living near the
line of starvation and that any aggravation of the adverse conditions
tends to increase the symptoms of nut fall.
In Zanzibar there is no attempt to manure the trees and very
little cultivation is done: moreover the rhinoceros beetle has increased
in recent years.
I shall be very grateful for any information which. you can give
me as to the occurrence of excessive nutfall and gummosis in other
countries and its treatment.
Mr. BAILEY said that this disease was very prevalent in the
coastal area of Kenya, and especially to the south of Mombasa where
it caused very considerable loss. The soil was very shallow and poor
in this district, with the exception of the river flats; and whereas the
disease was prevalent on the shallow soils he had not observed it on
the richer lands bordering the rivers where subsoil moisture was
avatlable.
THE CULTURE OF COCONUTS IN THE SEYCHELLES.
Mr. Fuller read a paper® submitted by the Director of Agriculture.
Seychelles (referred to in Agenda as T.C(C)Ag.17).
THE CONTROL OF THE RHINOCEROS BEETLE.
Mr. ANDERSON said that traps had been successful in Kenya,
and he would submit details to Miss Welsford.
Mr. RITCHIE stated that Oryctes monoceros also breeds extensively
 in the wild palms Borassus, Pheniz, and Hyphene, and In
decaying sisal bases.
* For text of this paper see Appendix.

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