2. PART IV.
and it appears to increase in importance from negligible proportions
at altitudes below 5,000 feet to a serious problem at about 6,000 feet.
Attempts are therefore being made to find answers to such questions
as the following:
What insect carries streak in Kenya?
What are its food plants?
Does it breed on maize or merely end its days on that host?
Does the insect thrive best at 6,000 feet or are its food plants
limited in distribution to red soils at the altitudes indicated ?
It is believed that answers to some of these questions may be
forthcoming shortly but, since nothing definite is known at present,
the methods of the writers of serial stories will be adopted and this
paper will end in an atmosphere of profound mystery.
REFERENCES
(1) Butler, E. J. Fungi and Disease in Plants, page 473.
(2) Dowson, W. J. Some problems of economic biology in East
Africa (Kenya Colony). Annals of Applied Biology, Vol.
VIII., No. 2, August, 1921.
18) Storey, H. H. Streak disease an infectious chlorosis of sugar
cane, not identical with mosaic disease. Report of the
Imperial Botanical Conference, London, July, 1924.
(4, Storey, H. H. The transmission of streak disease of maize
by the leaf hopper Balclutha mbila, Naude. Annals of
Applied Biology, Vol. XII., No. 4, November, 1925. :
Mr. RITCHIE, in six years, had only found head smut on maize
(Ustilago reiliana) on one occasion, but it occurred on both wild and
cultivated Sorgums. The disease had not made much headway in
Tanganyika, where the maize crop is grown under haphazard native
conditions.
BACTERIUM MALVACEARUM, E.F.S.
Mr. McDONALD said that very little cotton was grown in Kenya,
and this disease had never been sufficiently important for investigation.
BROWN BAST DISEASE OF HEVEA.
The Section regretted that it was not in a position to reply to this.
OHAPTER VI.
MISCELLANEOUS.
RECENT WORK IN THE CONTROL OF CUTWORMS.
It was agreed:
That the conditions and problems in South Africa are so
entirely different from those in the tropical East African Colonies,
that the problem is one for solution in the various territories
concerned.
COMPILATION OF LISTS OF INJURIOUS INSECTS.
Mr. ANDERSON explained that this question had been brought
up by the Kenya Agricultural Department, as it was felt that a
compilation, in the various territories, of injurious insects would be of
great benefit. He thought that it would be advisable that the pests
should be enumerated under the host plants and also systematically.

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