GIFT OF
AGRIC.
LIBRAH
MINI
TECHNICAL AND SCIENTIFIC SERVIC
Bulletin IVo.
(ENT. i ..OGICAL SE
THE LIFE HISTORY
THE TIM
nu ' )TTON HARV
P.T, I
ORGANIZATION OF THE MINISTRY OF AGRICULTURE, CAIRO, EGYPT.
Minister
Under-Secretary of State.
Consulting- Agriculturist .
inspector-General
W. Cartwright, M.A.,
T. L. Smith.
J. Wright.
R. W. Brigstocke.
H.E. Ahmed Helmy Pasha.
J. Haines.
Q. C. Dudgeon, F.E.S., Vice-President of the International
Association of Tropical Agriculture, Correspondent of the
International Institute of Agriculture, Rome, sto.
A. T. McKHIop.
PROVINCIAL INSPECTORS.
J. D. Shepherd.
H. M. Heaid.
C. A. Williams.
T. E. Bayne-Jardine.
Ibrahim Bey Fahmy.
Daoud Eff. Fat'hi.
Mohammed Eff. Kamel.
Mohammed Eff. Osman.
Director
Director
Entomologist!!
ADMINISTRATIVE AND STATISTICAL SERVICE.
„ ... Sadik Bey Henein.
ENTOMOLOGICAL SECTION.
L. H. Gough, Ph.D., F.E.S.
( Gilbert Storey, B.A., F.E.S.
, E. W. Adair, B.A., F.E.S.
HORTICULTURAL SECTION.
Director
Assistant- Director
Superintendent ...
T. W. Brown.
F. C. Walsingham.
C. S. Crouch.
BOTANICAL AND MYCOLOG1CAL SECTION, GIZA.
{Cotton. Breeding F'.trm «t Gha.)
Botanist B. G. C. Bolland, B.A.
CHEMICAL LABORATORY.
Chemist F. Hughes, F.C.S.
COTTON SEED DISTRIBUTION.
Director ... A. S. Morton.
BUREAU OF COMMERCIAL INTELLIGENCE.
Directed by the Consulting-Agriculturist.
Director
Pathologist
Veterinary Inspectors
VETERINARY SERVICE.
W. Littlewood, M.R.C.V.S. Egyptian Government Delegate,
International Quarantine Board, Egypt.
. F. E. Mason, M.R.C.V.S.
H. Cooper, M.R.C.V.S.
H. Mason, M.R.C.V.S.
E. de R. Gordon, M.R.C.V.S.
Principal
F. W. Trydell, M.R.C.V.S.
SCHOOL OF VETERINARY MEDICINE.
D. S, Rabagliati, B.Sc., Agrlo. (Edin.), M.R.C.V.S.
HIGHER SCHOOL OF AGRICULTURE, GIZA.
Director .........
Lecturer, Chein. and Agrlc.Chem. ...
Lecturer in Physics ........... .
Lecturer in Botany ............
Lecturer in Agriculture .........
Ernest Shearer, M.A., B.Sc.
G. Burns, B.Sc.
J. W. McPherson, B.A., A.R.C.Sc.
J. R. Davidson, M. A., B.Sc.
Alphonse M. Greiss.
MLMSTKY OF AGRICULTURE, EGYPT.
TECHNICAL AND SCIENTIFIC SERVICE.
Bulletin !\o. 4.
(ENTOMOIjOGIGAL SEGTIOX.j
t
THE LIFE HISTORY OF GKLEGHIA 0088YPIBLLA
FROM THE TIME OF THE COTTON HARVEST TO THE TIME
OF COTTON SOWING,
BY
LEWIS GOUGH, Pii.I)., F.E.S.. i:n ..
%
DIBBOTOH «>r THE KNTOMOUMJIOAI SHCTION.
ur I'l-'uillnij VH Man-It 39, I'Jlti.)
CAIRO.
(jrOVKUNMKNT
to l>f obtiiinod, ••ithi-r din-otly or through any l.uoksfllor.
II.MM III* UMVI:I:XMIAT I'IIBSS*, iiula'j. ;md I'rotn th« S A l,K- K"< > M .
(Mil I ni'iili i I'tilaijr, Shnrhi Qai-r el Aini.
1910.
PRICE P.T. I.
MINISTRY OF AGRICULTURE, EGYPT.
\o. 4.
(KNTOMOIA )( MGAL SECTION.)
THE LIFE HISTORY OF GELECHIA GOSSYPIELLA
FROM THE TIME OF THE COTTON HARVEST
TO THE TIME OF COTTON SOWING.
The whole problem of the. control of Gdechia gossypidla Saund.
is closely bound up with the solution of the question where and how
Gdechia passes the late autumn and winter.
As is well known in the summer, from June onwards, Gelechia
gossypidla passes through many generations, each of which lasts
only a few weeks. Each successive generation is immensely more
numerous and more important in the damage it does, than the preceding
one. Towards late autumn, however, we find a change; with the
advent of colder weather the larvae no longer pupate, but hibernate
unchanged when full fed, pupation taking place, on the advent of
warm weather, next spring.
The object of this paper is to show what happens with the seed
worm between the time of the first picking and the time of sowing,
this being the period during which the pest can be controlled most
effectively.
It is so well known to cultivators and ginners that it is not
necessary to insist on the enormous increase of the pest between the
first and second pickings. As a general rule the first picking is
affected only to a slight degree, whilst the second is seriously damaged,
and if the harvesting of a third picking were attempted, it would in
most places be found to be worthless. Four or five years ago three
pickings appear to have been the rule, but this year, owing .to Gdechia
attacks, few cultivators in Lower Egypt obtained a third picking.
The increase of the pest between the first and second pickings
can be most easily gauged by examination of commercial cotton s
— 2 -
Thus it was found that in a first picking sample only eighty seeds per
thousand had been damaged by the seed worm as against 377 seeds
per thousand damaged by this insect in a second picking sample,
showing an increase of 207 per thousand in damaged seed during the
interval of approximately six weeks that separates the first and second
pickings.
The extent of the increase in numbers at this period is, however,
not so interesting from the point of view of pest control, as is the
fact that during the harvest season (i.e. the period including the first
and second pickings) the life-cycle of Gelechia becomes modified, and
that it is soon after the first picking that the full fed seed worm inter-
calates a period of hibernation as larva before pupating.
Examining first picking seed in January a certain number of
Gelechia larvae are found hibernating, together with a number of dead
worms. These hibernating larvae were not necessarily full grown at
the time of picking, or of ginning; safely hidden in the " double"
seeds they can have finished feeding after both of these operations
were completed. In the case of the dead worms there is of course
nothing to show when or how they died. Taking the number of
living hibernating worms, found in January in first picking seed
and comparing them with the number of damaged seeds, six living
and thirteen dead worms were found to eighty damaged seeds, or
seventy-five living worms in one thousand damaged seeds.
For second picking seed the' numbers of hibernating worms
present in January are much greater. The sample we examined
contained 377 damaged seeds in every thousand seeds. In this case
118 living and fifty-six dead worms were found in the 377 damaged
seeds, or 313 living worms in every thousand damaged seeds.
The proportion of living worms found in January in one thousand
seeds (uninjured and damaged) in the sample examined consequently
works out at six per thousand in the case of the first picking and 118
per thousand in the case of the second picking.
The question immediately arises, what has happened to reduce
the proportion of living worms to damaged seeds so considerably
in the first picking seed as compared to the second picking seed.
A solution to this problem is offered by the observation that
very large quantities of larvae leave the seed and pupate on the sacks,
especially in first picking seed. The moths from these pupae emerge
— 3 —
during the winter, and apparently do not wander away from the
,sacks to any great extent. During December, January, and February,
it is always possible to find immense quantities of dead moths in the
accumulation of dust and dirt that collect on and between the sacks
in a seed store. For example, scrapings off sacks containing first
picking seed taken in February at Kafr el Zayat were found to contain
large quantities of dead moths. Ten grammes were examined and
found to include 248 dead moths, forty-four empty pupa cases, and
two dead larvae.
In second picking seed at the same time of the year, the worms
are mostly still in the seeds, and have not emigrated to pupate.
This leads one inevitably to the conclusion that the worms in
the seed at the time of the first picking do not to any great extent
hibernate, but that they pupate and emerge during the course of the
next few months. A further conclusion is that for want of suitable
food plants, or on account of the cold weather, the majority of these
moths do not propagate their species.
The main danger consequently lies in the worms which were
not full fed at the time of the first picking. If it were possible at the
time of the first picking to destroy all the cottoa plants and immature
bolls, the damage to be anticipated from GeLechia in the next season
would be very slight. Such a procedure is, however, impossible on
account of the great financial loss involved by rejecting the second
picking.
A recommendation can, however, be made to reserve first picking
for sowing, and either to crush or export all second picking seed as
soon as possible. Alternatively the second picking seed could be
treated by heat or poisonous gas to kill all the worms contained,
should it for any reason be desired to keep it in Egypt. Similar
treatment of first picking seed is not so necessary but would be
useful.
Not all the worms that having left the seed wander about in a
seed store, pupate on the sacks. A small minority is to be found in
other places. Sweepings were taken in February in a seed store at
Kafr el Zayat. 639 grammes were examined, which consisted of
113 grammes of cotton seed, 95 grammes of stones or straw, and
431 grammes of dust. In this material three larvsS were found, of
which two dead. The living larva was discovered in the dust, the
— 4 —
two dead ones in the seed. Of one thousand of the seeds 154 had
been damaged by seed worm.
A further recommendation is that, if possible, all seed cotton
stored in Egypt after January 22 of each year should be kept in
moth-proofed stores, and that cotton seed be permitted to remain
unprotected until after planting is finished. Before this date it
might be kept in open stores without much harm, provided they are
sprayed and swept periodically, as the majority of larvae emigrating
from seed and seed cotton before then will belong to generations
bred in the first picking cotton; these larvae can be expected to
pupate and the moths to emerge during winter and early spring ;
such moths not finding foodplants to oviposit on are lost for the
propagation of the species, whilst the hibernating larvae from the
later seed are not yet leaving the seed. Of course it would be better
if all cotton seed and seed cotton could be stored in moth-proofed
stores, from the time of picking until ultimately disposed of, but
it is not possible to interfere to so great an extent with ordinary
practice.
Leaving the question of cotton seed and seed cotton in stores on
one side, the much more important question arises as to the fate of the
larvae left in the fields after the last picking.
Under the old boll worm law, which was intended to restrict
Earias insulana Boisd., all cotton sticks have to be pulled up by
December 31 of each year. This is in order to reduce the quantity
of oqr or ratoon cotton which in the spring could offer breeding
grounds for Earias larvae. The law further ordered all bolls to be
removed from the sticks before December 15 in order to destroy the
last generation of Earias.
At first it was hoped that vigorous enforcement of this law would
also help to check Gdechia gossypiella. It has without doubt made
Earias insulana much rarer this winter (1915-1916) than it used
to be only four years ago, but in the case of Gdechia the result has
not been appreciable.
At the time of pulling the sticks great attention has been given
to the removal and burning of the bolls, and the Ministry of Agriculture
has caused large quantities of badly cleaned sticks to be burnt. To
affect Gdechia gossypiella this work ought to be carried out at a much
earlier date than prescribed by the Boll Worm Law (Earias Law),
— o —
and much more attention would have to be paid to preventing bolls
falling to the ground and being left there to rot. In combating
Earias, bolls left on the ground did not have the same significance as
they have in the control of Gelechia.
It can be considered as certain that all Gelechia larvae arriving
at maturity after the middle of October are going to hibernate before
pupation. As we have seen above, it is the hibernating larvae which
arc chiefly responsible for carrying on the pest from one season to the
other. The later the bolls are left on the plants or in the field, the
more certain they are to be infested by Gelechia larvae. It is con-
sequently urgently to be recommended that the final destruction of
immature or worthless bolls should take place at the time of final
picking.
It has been almost impossible this year to obtain bolls for exam-
ination in January from cotton sticks or from cotton plants left
standing in the fields or stored as fuel. That such bolls are a favourite
hibernating place for Gelechia larvae is well known. We have, however,
been able to examine a number of bolls collected at Giza in October
1915. These bolls were stored in the insectarium of the Entomological
Section, no special care being given to them. On February 21, 1916,
seventy-six bolls were examined and were found to contain five small,
eight half-grown, and thirty-nine full-grown living Gelechia larvae,
fourteen dead larvae, and two empty pupa cases of Gelechia. In addi-
tion to these three empty pupa cases of Pyroderces gossypiella Wlsm.,
one Earias insidana pupa, and one dead Pimpla roburator F. were
found. Seventy-five cotton bolls found on sticks, used as supports
fcr peas, were collected in a garden near Cairo in February 1916; these
contained two small, three half-grown, and one full-grown Gelechia
larvae.
The destruction of the bolls to be really effective must be complete.
Fellahm do not realise that bolls fallen to the ground are as great a
menace to the next year's crop as bolls left on the cotton sticks, and
very much more serious than the worms left in the seed.
In order to ascertain what happens to worms in bolls lying on
the ground, two sets of examinations have been made. In one case
bolls have been collected from the ground in the field amongst growing
crops, in the other, seed and bolls containing worms have been buried
at various depths under growing bersim as well as in unwatered land.
The following monthly results have been obtained by the end of
March (at the time of sowing the 1916 crop).
Bolls were collected in fields under beans, wheat, barley, and
bersim, in the neighbourhood of Shibin el Qanater, on December 26, 19 1 5,
January 23, February 16, and March 18, 1916 (see Table I).
About two hundred and thirteen bolk were examined in
December. These contained twelve small, five half-grown, and twenty
full-grown living larvae, besides two living pupae and ten empty pupa
cases of Gdechia.
Three hundred and fifteen bolls were examined in January,
containing sixteen small, twenty-one half-grown, and forty-three full-
grown living larvae and eighteen empty pupa cases of Gdechia.
Two hundred and forty-three bolls were examined in February,
containing five small, forty-seven half -grown, and fifty-two full-grown
living larvae and nineteen empty pupa cases of Gdechia.
Two hundred and thirty-nine bolls were examined in March,
containing one small, four half-grown, and forty-nine full-grown
living larvae, two living pupae, and sixteen empty J pupa cases of
Gelechia.
It will be noted that no living pupae were found in January or
February and that they again occurred in March. The pupae found
in March doubtless belonged to the hibernating generation of worms,
those found in December to the last maturing generation of the pre-
vious autumn.
Attention is also drawn to the steady increase in the proportion
of the worms present in the bolls during December, January, and
February, and the obvious decrease in March. This decrease is very
probably to be considered in connection with the emigration of full
fed larvae previous to pupation.
It becomes very obvious from the study of Table III that during
the winter months two generations of Gdechia larvae are found in the
bolls on the ground.
The older of the two generations, the hibernating generation,
consists entirely of full-fed worms. These form about fifty per cent
of the total of worms found in December, January, and February ;
and without doubt compose part at least of the, eighty-eight per cent
of full-grown larvae found in March. There are, however, indications
that many of the worms of the hibernating generation must have
emigrated to pupate, or pupated by the end of March,
_ IT
The younger of the two generations is the winter-feeding brood.
From the figures given in the table it is quite easy to trace the
slow growth of the individuals composing it during December, January,
and February. By March all but nine per cent of this generation were
full fed. As the last picking in the fields from which these bolls were
collected took place on October 26, and the cotton sticks were removed
from the fields on or before November 3, 1915, there appears to the
writer to be considerable probability that the eggs from which the
larvae forming the winter-feeding generation were derived must have
been laid on bolls on the ground. Should this be actually what
happens, bolls left on the ground after the last picking acquire a still
greater economic importance than they already had.
Having found that Gdechia larvae readily survive in bolls lying on
the surface of the ground amongst cultivated crops, where the bolls
are liable to rot and where they must be- submerged every time the
fields are irrigated, it is not surprising to find that many of the larvae
that are buried at the time of preparing the ground for the crops
survive. As it was difficult or even perhaps impossible to find such
bolls by digging in the fields, experiments in thii direction were made
in the grounds of the Ministry of Agriculture at Cairo.
Seed containing larvae and "double" seeds were used, on account
of the difficulty in procuring bolls at the time when the experiment
was started (December 23, 1915). Two series of experiments were
made ; small flower pots were prepared by having the drainage hole
being stopped by plaster of Paris. One set of these pots, Series I, was
filled with apparently good cotton seed, fifteen full fed Gdechia larvae
placed in the seed, the pots were then closed by tying muilin over the
opening. In the second set, Series II, the pots were filled with infested
seed (" double " seed) instead of sound seed with isolated larvae.
The further treatment of both these sets of pots was exactly the
same. One half of them were buried in dry ground, in land left
unwatered except by rain, the other half was buried in land on which
a crop of bersim was grown.
To test the influence of depth at which the seed was buried part
of the pots were lowered until their tops were five, ten, fifteen, and
twenty centimetres from the surface.
From these experiments the depth factor does not appear to be
an important one, and Gdechia larva) seem to support being buried
— 8 —
in moist or dry conditions very well (see Table II). On January 23,
when the first examination was made in the infested seed (Series II),
eighty-one living and seventeen dead were, found in the pots which
had been buried under growing bersim, and 113 living and seventeen
dead in the pots buried in unwatered land.
The "good" seed (Series I), gave similar results; here twenty-five
living and eighteen dead larvae were found Jn the pots buried under
bersim, and twenty-three living and five dead in the pots buried in dry
soil. Forty-nine larvae had disappeared. This disappearance is not to
be wondered at, as the gauze covering the pots had rotted away
entirely.
Two months were supported quite as well as four weeks inter-
ment had been. On February 23, further sets of pots were dug up
and examined. The pots containing " infested " seed (Series II)
buried under bersim yielded 153 living Gelechia larvae and eighteen
dead ones, those buried in dry soil 132 living and six dead seed worms.
No pupae were found.
In the ''good" seed (Series I) fifteen living and four dead larvae
were recevered from pots buried under bersim, one dead and twenty-
four living worms from the pots buried in dry land; seventy-six
larvae had disappeared.
Although there were no double seeds in the "good" seed pots at
the time of burying (December 23, 1915) several were found when
the pots were examined, showing that some of the larvre had spun
seeds together in the interval. The instinct to spin up seeds appears
to have been stronger in the case of worms in moist surroundings.
Attention is specially drawn to the fact that a very large majority
of the worms were found inside seeds in Series I.
Three months' burial were also supported by a part of the worms.
The numbers of worms found were, however, distinctly less than those
recovered in the earlier examinations, possibly on account of emigra-
tion for pupation.
From these experiments it would appear that the hibernating
or full-fed larvre survive even if ploughed under or buried in seed,
or in bolls, and that they can exist for long periods under these condi-
tions.
Consideration of all the facts submitted in this paper makes it
appear probable that hibernation of full-fed larvae is induced by the
temperature of their surroundings at the time of their reaching maturity.
Moisture or dryness does not under certain limits appear to affect
their hibernation. The period of hibernation can also be very pro-
tracted given the right conditions. Thus hibernating larvae were
found in seeds taken from some Indian cotton imported by an Alex-
andria firm in January 1914, when the cotton was re-ginned and the
seeds examined in December 1915. These larvae must have belonged
to the last generation before the cotton was picked in India in Sep-
tember 1913, and they must have been considerably over two years
old. They were found in Desi cotton seed.
Similarly in cotton seed from the 1914 crop, one thousand
damaged seeds were examined in February 1916, and three living
Gdechia larvae were found. These larvae must consequently be
at least sixteen months old.
CONCLUSIONS.
1. The larvae of Gdechia, gossypietta maturing after the first
picking intercalate a period of suspended or lessened activity, or
hibernation before pupating. This period normally extends to the
next spring or summer, but can last at least two years.
2. The larvae reaching maturity before or at the time of the first
picking mostly pupate and emerge as moths during the next few
months, but before the next crop season.
3. There are two broods of larvae to be found during the winter,
a hibernating and a winter- feeding brood; these are the most fertile
source for re-establishing the pest in the next season.
4. The moths emerging in autumn and winter are to a great
extent lost for the maintenance of the species, and will be still less
important if destruction of bolls on cotton sticks stored for fuel or
lying on the ground is properly carried out.
5. During the winter hibernating larvae are to be found in cotton
seed and seed cotton, and are very much more numerous in second
picking than in first picking material. Still greater numbers remain
in bolls left on cotton sticks, unless destroyed there, or in bolls left
in the fields to rot. At the time of sowing, such bolls still contain
enormous numbers of living Gdechia larvae. Burial under growing
irrigated crops does not affect the vitality of these larvae.
— 10 —
6.. Efficient control is only possible if the destruction of all bolls
is systematically undertaken at the time of the last picking, the bolls
on the ground, or even buried bolls, being as important as those left
on the cotton sticks. Cotton seed (other than for sowing) and seed
cotton stored after the middle of January ought to be kept in moth-
proof stores, and all cotton seed intended for sowing (excepting
perhaps first picking seed), ought to be treated by heat or poisonous
gas before distribution. All other cotton seed ought to be exported
or crushed before April 1, unless it has been treated in the same way.
7. The order of importance of the methods of control are : —
(a) Destruction of bolls as early as possible, earliness being an
important factor ; (b) moth-proofing of all stores intended for the
storage after January of cotton seed and seed cotton (except seed
kept for sowing); (c) treatment of all seed intended for sowing, and
immediate exportation, crushing or treatment of all the remaining
cotton seed.
8. None of these methods of treatment can be efficient alone,
and unless all three are universally and thoroughly applied. Treat-
ment of the seed alone cannot be expected to give any appreciable
results.
TABLES.
— 12 —
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— 13 —
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— 14 —
TABLE II. — Experiments to Demonstrate the Power of Gelechia Lar
Experiments starl
SEUIES ].— I'OTS KILLED WITH " GOOD " SEED: FIFTEEN FULL-FED LAKVVK WEBB PLACED IN EACH P<
Conditions to which the Pot was subjected.
Gelechia LarvfE.
fl
o
Serial
No.
of Pot.
Buried.
Depth in
Cen-
timetres.
Time
of Exposure.
,,,„„,
Dead.
sl
' Remarks.
65
) Under Bersim I
5
One month.
4
9
.
66
sown
10
5)
4
•)
^H
e»
67
( December 23, ')
15
5,
9
5
68
) 1915. (
20
<S
2
§f
69
| In unwatered (
5
8
2
.^
70
land which, J
10
3
1
C
09
71
( however, became j
15
5
1
0
72
) wetted by rain. (
20
N
7
1
CS
49
Under Bersim I
5
Two months.
3
2
to
50
sown
10
7
1
s
51
December 23, )
15
3
0
^
52
1915. (
20
59
o
]
S5
53
} In unwatered (
5
,,
11
1
b
54
land which,
10
1
0
p
55
( however, became j
15
7
0
,^
56
) wetted by rain. (
20
»
5
0
fe
33
) Under Bersim I
5
Three months
5
9
1 pupa in 34.
;54
sown
10
5
0
3
35
( December 23, )
15
•
1
0
Oi
36
) 1915. (
20
„
1
L
jrf
37
j In unwatered I
5
n
7
1
s
1 pupu in 3'.).
38
( land which,
10
2
0
o
39
( however, became j
15
1
1
£
-
40
) wetted by rain. (
20
„
1.
0
Totals for the .January Examination.
65-68
69-72
Under Bersim
In dry ground
—
One month.
»
25
23
18
5
—
49-52
53-56
Tot
Under Bersim
In dry ground
als for tli
e February I
Two months.
«
jxamin;
15
24
ition.
4
1
—
Totals for the March Examination.
33-36
37-40
Under Bersim
In dry ground
—
Three months
„
12
11
10
2
—
Totals for three Months.
—
Under Bernini
In dry ground
Together
—
—
52
58
110
32
8
40
—
to Survive when buried under a Growing Crop or in Dry Soil.
December 23, 1915.
— 15 —
SERIES 2.— POTS KILLED WITH INFESTED SEED CONTAINING A LARGE NUMBER OP DOUBLE SEEDS.
THESE DOI-BLK SEEDS WERE NOT OPENED IN' ORDER TO AVOID DISTURBING THE LARV.K UNNECESSARILY.
Conditions to which the Pot was exposed.
Gielechla, Larvae.
,.;
Serial
*o '-3
No.
of Pot.
Depth in
Buried. Cen-
timetres.
Time
of Exposure.
Living.
Dead.
v a
81
K
«
Remarks.
57
i Under Bersim ( 5
One month.
26
6
O
58
sown 10
15
4
59
60
December 23, \ 15
1915. ( 20
»
15
25
5
2
s
Pots 1-24 will bu
examined in April.
61
iln onwatered ( 5
19
4
62
land which, J 10
35
11
2
63
however, became ) 15
•
19
1
q
64
wetted by rain. (
20
»
40
1
1
41
Under Bersim I
5
Two months.
31
1
te
42
sown
10
63
8
i— i
Ci
43
December 23, )
15
32
6
^H
44
1915. (
20
27
3
CO"
45
iln unwatered 1
5
37
2
b
46
land which, (
10
20
1
B
47
however, became (
15
42
2
c
48
wetted by rain. J
20
„
33
1
£
25
} Under Bersim )
5
Three months
11
1
20
sown (
10
13
t;
j®
1 pupa in 15.
27
December 23, f
15
10
i
S
1 pupa in 26.
28
1915. )
20
,5
4
0
«f
29
In unwatered j
5
5
0
IM
30
land which, (
10
8
0
8
1 pupil in 3(1.
31
however, became (
15
8
4
1 pupa in 31.
32
wetted by rain.
20
„
9
0
"
Totals for the January Examination.
57-00
BI-64
Under Bersim
In dry ground
—
One month.
,5
81
113
17
17
—
Totals for the February Examination.
41-4J
45-4S
Under Bernini
In dry yround
—
Two months.
»
153
132
18
6
—
Total for the March Examination.
-'5-28
j'.i :;:.'
Under Bersim
In dry ground
—
Three months
38
30
8
4
—
Totals for three Months.
—
Under Bet-si m
In dry ground
Together
—
—
272
275
547
43
27
70
—
— 16 —
1
I
>« o o •*
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OH
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examined
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Govt, Press 0020-1910-1.030 ex.
7 DAY USE
RETURN TO DESK FROM WHICH BORROWED
AGRICULTURE LIBRARY
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This publication is due on the LAST DATE
and HOUR stamped below.
m^$?\
NOV 1. 4 1985
received in
Natural Hesouices L.lvary
NiiV? C iHH5
PHOTOCOPY JUL 6
<x
"88
«T
; •
fVU'/ctf^ -o
&*]_ 1389
*&
RB 17-50m-3,'70
(N5381slO)4188-A-32
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University of California
Berkeley
• r.
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