PART IV. ?
In Tanganyika the only known alternative food-plant is the Okra
(Hibiscus esculentus), whilst in Egypt the ascertained alternative
food-plants are Hibiscus esculentus, Hibiscus cannabinus, and
Hollyhocks.
Interesting points in this connection are that, in Tanganyika one
of the most important parasites of the Pink Boll worm is only found
attacking the larva infesting the Okra, not those infesting Cotton; and,
further, that the larva infesting the Okra pupates in the pod and not
in the soil. As one delegate suggested, it may be that the form in
the Okra is similar to that found infesting Hibiscus in Uganda, more
especially as in Queensland two distinet Pink Boll worms are also
known, one attacking Cotton and one restricted to Hibiscus.
4. Pink Born Worm IN GINNERIES.
From observations made by Mr. Ritchie, there appears to be a
distinct danger of Pink Boll worm being spread from ginneries.
5. ApeqQuacy oF METHODS OF DISINFECTING IMPORTED COTTON SEED.*
The general trend of the remarks made in this connection were
to the effect that certain methods were adequate, but that certificates
to the effect that such methods had been employed were not to be
wholly relied upon. In other words, examination and effective
treatment at the port of entry was absolutely necessary.
In this connection, it is suggested that each African Territory be
asked to furnish a return showing the source of origin, the covering
statement and condition of any cotton-seed found to be infested with
Pink Boll worm when examined.
SECTION III.
THE SUDAN BOLL WORM} (Diparopsis castanea).
(a) DISTRIBUTION AND STATUS.
The Sudan Boll worm does not appear to have become established
nor to flourish in Uganda, Tanganyika, and Kenya. It is a serious
pest in Nyasaland, Portuguese East Africa, and South Africa: it is
known to be present in the Belgian Congo. It is not possible to
review its distribution farther afield.
In Nyasaland the insect is widely distributed—the most serious
cotton pest and the chief limitation of cotton growing.
In Portuguese East Africa, the Sudan Boll worm occurs wherever
cotton is grown. It is a very serious pest—the worst of cotton pests
and, in places, is responsible for 809, loss of crops.
In South Africa, it is a very serious pest and, except for parts
of the Cape Province, occurs wherever cotton is grown.
(b) History AND Hairs.
As regards the general history of this insect in places where it is
not considered a major pest, it is impossible to furnish the Empire
Cotton Growing Corporation with any information.
© See also page 183.
I See also page 182.

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