ENCLOSURE TO PART 1V.
A NEW BOLL WORM.
Mr. Hargreaves related the occurrence in Uganda of a new bollworm,
 Argyroploce sp.*
APHIDS AND JASSIDS.
The Chairman read notest by Mr. Haines.
Mr. HARGREAVES stated that in Uganda the Aphids was
perhaps the most serious pest on cotton; certainly the accumulated
effect appeared to be greater than that of anv other insect.
Mr. RITCHIE suggested that the control of Aphids and Jassids
by fungi might be further investigated; a fungus was the most potent
controlling factor of Aphis in Tanganyika, and he instanced the
success of a fungus as the controlling factor of West Indian cane
hopper, Delphax sacchernora.
This suggestion was accepted by the Section.
Mr. HARDENBERG was experimenting with nicotine dust and
Bordeaux mixture in the control of Jassids.
OCCURRENCE OF MAJOR PESTS.
The Chairman read notes§ by Mr. Haines.
The Section accepted the position as put forward by Mr. Haines,
and agreed :—-That
 a wider survey was necessary before any definite
information could be supplied.
COTTON STAINER (DYSDERCUS SPP.)
The Chairman read the following paper (referred to in Agenda as
T.C. (C)Cot.15), which had been submitted by the Southern Rhodesian
Government : —
Two species of varieties of Dysdercus, namely D. intermedius,
Dist. and D. nigrofasciatus, Stal. are extremely prevalent in their
season in Southern Rhodesian cotton fields. It is clearly desirable
that the relation of these abundant insects to the cotton crop should
thoroughly be understood.
The economic status of an insect in any particular area must
obviously be determined by local investigation, but experience in other
areas is helpful in indicating a direction to such local research. In
consulting available literature, some difference of opinion in respect
to these insects in different cotton growing countries is apparent.
It is desired to make it clear at the outset that the present writer
is wholly concerned in seeking information and has nothing in the
way of experimental results to impart. His object is merely to place
certain difficulties before the Conference and if possible to obtain an
answer to one or two questions.
The genus Dysdercus appears to be of almost universal occurrence
in the tropics and is apparently represented by one or other of its
species in practically all cotton growing countries. The different
species seem to have quite similar habits and it appears permissible
to deal with the genus as a unit.
See also page 171.
For text of these notes see page 173.
- For text of these notes see page 172.

238