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Florida Entomologist
Official Organ of the Florida Entomological Society
Vol. XV SUMMER NUMBER No. 2
AUGUST, 1931
BIOLOGY OF THE MEXICAN COTTON BOLL WEEVIL VII:
THE BOLL WEEVIL IN ARTIFICIAL HIBERNATION QUARTERS'
By EDGAR F. GROSSMAN
Repeated experimentation with the conventional type of hiber-
nation cages in which cotton boll weevils (Anthonomus grandis
Boh.) were placed re-
sulted in the construe- ,*
tion of a new type hiber- ,
nation cage in which
various factors which in-
fluence the hibernation
phenomena could be con-
sidered individually. The
new type cage consisted
of a 16-mesh screen cyl-
inder measuring nine
feet in length and about
one foot in diameter.
Nine smaller tubes meas-
uring 12 inches in length
and three inches in di-
ameter were inserted
horizontally along the
cylinder wall at one foot
intervals. The nine foot
cylinder was not equip-
ped w i t h hibernating
materials but each one Fig. 1.-Three cylindrical hibernation cages
of the smaller tubes was with the inserted tubes filled with Span-
filled with Spanish moss, ish moss.
as illustrated in Fig. 1. The open ends of the tubes were fitted
with corks.
'Contribution from the Department of Cotton Investigations, Florida
Agricultural Experiment Station.
THE FLORIDA ENTOMOLOGIST
By the use of this type cage the geotropic influences exerted on
the boll weevil when it seeks hibernation quarters can be studied.
Likewise the influence of moisture can be determined by wetting
the Spanish moss in alternate tubes or in sections of adjacent
tubes. Furthermore the number of weevils which enter hiber-
nation in the smaller tubes can be noted, thereby providing
means for the interpretation of weevil survival based on the
number of weevils which actually entered hibernation rather
than on the total number of weevils placed in the cage.
Frequent observations made while boll weevils emerged from
their hibernation quarters in an 8x8x8 foot cage indicated that
the majority of the weevils emerged from the uppermost layer
of Spanish moss which was supported about six feet above the
ground, on a tree trunk.2 Very few weevils emerged from the
moss which was packed about the bottom of the cage. These
observations indicated that the boll weevil was negatively geo-
tropic when seeking quarters in which to hibernate.
By liberating weevils at the bottom, in the mid-section and
at the top of individual cylindrical cages, respectively, the geo-
tropic influences exerted on the weevil could be detected. The
weevils, in their search for hibernation quarters, entered the
moss-filled tubes which ranged from one to nine feet above the
ground. Subsequent counts of the numbers of weevils entering
each tube were made. Data were secured from a total of 24
cages which were used for experimentation for three consecu-
tive years: in eight of the cages the weevils were liberated at
the bottom; in eight at the middle; and in eight at the top. The
data secured from the combined series of eight cages show a
marked similarity in view of the fact that the largest percent
of the weevils entered hibernation in the uppermost tube, though
the series in which the weevils were liberated at the top showed a
great increase in the number of weevils which entered hiberna-
tion in the top tube. Whether the weevils were liberated at the
bottom or in the middle of the cage apparently made little dif-
ference in the weevil dispersion. These data are presented in
Table I.
The fact that the weevils were confined in the cages during
daylight and therefore might have been influenced by photo-
tropic influences which in turn might have caused them to crawl
toward the top of the cage, was also considered. A test including
'Grossman, Edgar F. Diurnal Observations of the Emergence of Boll
Weevils from Their Hibernation Quarters. The Florida Ent. Vol. XIV. No.
3, pp. 45-52, Sept. 1930.
SUMMER NUMBER
a series of three cages in which the weevils were liberated at the
bottom, middle and top of each cage, respectively, was con-
ducted in a cooled dark-room. In the absence of light the weevils
reacted as they did in the presence of light. The assumption
therefore that geotropic influences caused the majority of the
weevils to hibernate in the uppermost tubes seems tenable.
TABLE I.-THE NUMBER AND PERCENT OF WEEVILS FOUND IN THE NINE,
TUBES FILLED WITH SPANISH MOSS DURING EXPERIMENTATION WITH
24 CAGES.
Number of Section of cage in which weevils were placed
moss-filled Bottom I Middle I Top
cage tubes Number Percent of Number Percent of Number Percent of
(from top weevils total num- weevils total num- weevils total num-
to bottom) found ber found found ber found found ber found
1 692 33.02 786 32.52 1,133 58.34
2 301 14.36 573 23.71 243 12.51
3 251 11.98 225 9.31 179 9.22
4 145 6.92 219 9.06 84 4.33
5 124 5.92 156 6.45 58 2.99
6 123 5.87 152 6.29 45 2.32
7 147 7.01 96 3.97 60 3.09
8 170 8.11 79 3.27 53 2.73
9 143 6.82 131 5.42 87 4.48
Totals ......... 2,096 100.01 2,417 100.00 1,942 100.01
Other experiments devised to determine the influences of mois-
ture were also conducted in a cooled dark-room. In one cage the
Spanish moss in the bottom four tubes was moistened and the
weevils were liberated at the bottom of the cage. In the second
cage the moss in the alternate tubes was moistened and the
weevils were liberated in the middle of the cage. In the third
cage the moss in the four uppermost tubes was moistened and
the weevils were liberated at the top of the cage. Where the
bottom tubes were moistened the greatest number of weevils
entered hibernation in the lower tubes. In the cage where the
upper tubes were moistened the greatest number of weevils
entering hibernation were found in the uppermost tubes. Where
the alternate tubes were moistened a slight deviation from the
average distribution which had been previously determined when
the moss was not moistened was noticeable. The data are pre-
sented in Table II. The indications are that moisture is a factor
which can be assumed to attract boll weevils to the quarters in
which they hibernate.
THE FLORIDA ENTOMOLOGIST
TABLE II.-DISTRIBUTION OF BOLL WEEVILS IN THREE CYLINDRICAL HIBER-
NATION CAGES EQUIPPED WITH NINE TUBES FILLED WITH SPANISH MOSS.
SNum r of section of cage in which weevils were placed
Number of
moss-filled Bottom I Middle Top
cage tubes Numberl Percent of Numberl Percent of Number Percent of
(from top weevils I total num- weevils total num- weevils total num-
to bottom) found ber found found ber found found ber found
1 22 10.05 *69 *20.97 *137 *56.15
2 10 4.57 56 17.02 *38 *15.57
3 15 6.85 *42 *12.77 *16 *6.56
4 15 6.85 32 9.73 *8 *3.28
5 22 10.05 *45 *13.68 5 2.05
6 *21 *9.59 29 8.81 4 1.64
7 *31 *14.16 *14 *4.25 9 3.69
8 *38 *17.35 22 6.69 12 4.92
9 *45 *20.55 *20 *6.08 15 6.15
Totals 219 | 100.02 I 329 100.00 244 100.01
*Denotes tubes containing wetted Spanish moss. Other tubes dry.
It is not surprising therefore that in Florida cotton growers
have been forced to move their cotton planting away from areas
neighboring ponds and in which theie were Spanish moss-laden
trees, since the weevils hibernated there so successfully and
reappeared in the fields in such large numbers that the use of
control methods involved too much expense for producing cotton
economically.
Hibernation cage data is usually interpreted on the assump-
tion that when groups of weevils are caught in the cotton fields
each group contains practically the same percent of weevils
which are prepared for hibernation and that they will subse-
quently enter hibernation in equal numbers on being confined in
the hibernation cage. The resultant emergence data, however,
are very irregular when the survival percentages of the suc-
cessfully over-wintered weevils are considered. The discrep-
Sancies are, in all probability, due to the fact that the survival
percent are based on the number of weevils placed in the cage
-regardless of their condition-rather than on the number of
weevils which actually entered hibernation.
In the fall of 1927, over 20,000 weevils were placed in a large
hibernation cage during a period extending over three weeks.
About a week after the last weevils had been placed in the cage
a total of 2,100 weevils were found dead. Subsequent exam-
ination of other hibernation cages showed a similar high rate
of mortality of weevils which occurred during the initial period
of confinement in the cages. Obviously the interpretation of the
data which were accumulated to record the percent of winter
SUMMER NUMBER
survival in the light of offering information relative to the spring
infestation which might be expected, met with the embarrassing
question whether or not the number of weevils which died before
they entered hibernation should be deducted from the total num-
ber placed in the cage. Since a thorough search for the dead
weevils could not be made, a condition due to the inadvisability
of disturbing the debris in which other weevils had hibernated,
the survival data generally have been based on the number of
weevils which had been placed in the cages. The construction
of the new type cylindrical hibernation cage, however, provided
means for determining the number of weevils which failed to
enter hibernation without disturbing the weevils which had
entered.
TABLE III.-THE NUMBER AND PERCENT OF WEEVILS WHICH ENTERED HI-
BERNATION AND THE NUMBER AND PERCENT OF WEEVILS WHICH DID NOT
ENTER HIBERNATION IN 24 CYLINDRICAL CAGES.
w 'o
ab
B9
ES^
^i-^ C3
1^"a
1 300
2 300
3 300
4 1,000
5 1,000
6 1,000
7 1,000
8 1,000
9 1,000
10 1,000
11 1,000
12 1,000
13 1,000
14 1,000
15 1,000
16 1,000
17 1,000
18 1,000
19 1,000
20 1,000
21 1,000
22 1,000
23 500
24 500
*Not recorded
162
16
88
359
236
107
223
163
140
121
324
103
490
346
478
463
528
265
269
438
334
329
244
219
~4-
ao
54.0
5.3
29.3
35.9
23.6
10.7
22.3
16.3
14.0
12.1
32.4
10.3
49.0
34.6
47.8
46.3
52.8
26.5
26.9
43.8
33.4
32.9
24.4
21.9
r.
120
37
34
634
749
397
328
509
604
642
611
211
510
586
522
494
345
407
397.
328
509.
0
8
247
178
7
15
496
449
328
256
237
65
686
0
68
0
43
127
328
is
P-1
46.0
94.7
70.7
64.1
76.4
89.3
77.7
83.7
86.0
87.9
67.6
89.7
51.0
65.4
52.2
53.7
47.2
73.5
Of the 20,900
bernation cages,
weevils which were placed in 24 cylindrical hi-
a total of 6,445 or 30.84 percent entered hiber-
THE FLORIDA ENTOMOLOGIST
nation. The other weevils either died before entering hiberna-
tion and were subsequently carried off by ants, or escaped. A
list of the number of weevils placed in each of the 24 cages, the
number and percent found hibernating and the number and
percent of the weevils which did not enter hibernation are pre-
sented in Table III. The weevils were all captured on November
6, 7 and 8, which is generally the most favorable time for plac-
ing weevils in hibernation cages in Florida. Nevertheless, the
percent of the weevils which entered hibernation varied in in-
dividual cages from 5.3 percent to 52.8 percent. Consequently,
the survival percentage, when computed from the total number
of weevils placed in the cages would vary considerably also.
In order to illustrate this point more clearly nine of the cylin-
drical cages were examined at intervals extending from 44 to
162 days after the weevils had been placed in the cages. The
percent survival, when based on the number of weevils which
were placed in the cage (1,000 specimens in each cage) varied
from 5.4 percent to 29.7 percent. When, however, the survival
percent was based on the number of weevils which entered hi-
bernation the variation was greatly reduced, extending from 50.5
percent to 85.9 percent. These data are presented in Table IV.
TABLE IV.-INTERPRETATION OF BOLL WEEVIL SURVIVAL BASED ON THE NUM-
BER OF WEEVILS PLACED IN HIBERNATION CAGES AND ON THE NUMBER OF
WEEVILS WHICH ENTERED HIBERNATION.
SS 4I F.S Percent weevils living
'- j a On basis of On basis of number
e :j 0 1,000 weevils weevils which entered
Placed in cage hibernation
1 Dec. 20 44 17.0 67.4
2 Jan. 4 59 8.2 76.6
3 Jan. 25 80 29.7 80.2
4 Feb. 8 93 19.0 84.8
5 Feb. 22 107 14.2 85.9
6 Mar. 8 121 8.3 58.6
7 Mar. 22 134 7.2 57.9
8 Apr. 5 148 22.9 68.5
9 Apr. 19 162 5.4 50.5
Of especial significance are the three cages which were examined
on March 22, April 5 and 19, respectively. The counts based on
the total number of weevils placed in the cages shows that 7.2
percent, 22.9 percent and 5.4 percent respectively, survived.
The counts, however, in which only those weevils which entered
hibernation were included in the calculations shows that 57.9
percent, 68.5 percent and 50.5 percent of the weevils survived.
SUMMER NUMBER 27
With this interpretation of hibernation cage data in mind the
great variations which occur from year to year, or even during
the same year in different cages, can be better understood.
With the exception of the'first two groups (Table IV) the
weevils which were removed from their hibernation quarters
in the cylindrical cages were placed in a low temperature incu-
bator kept at 47F. and from 79 percent to 85 percent relative
humidity." The rate of survival of the weevils is presented in
Table V. A large percentage of the weevils lived until May 31,
the time when they first appear in the cotton fields in large
numbers. A month later many weevils were still alive, but
by August relatively few of the weevils lived. Hibernation of
the weevils in cages exposed to varying temperatures and rel-
ative humidity appears to be attendant with the same success
as the hibernation of the weevils kept at a constant optimum
temperature and relative humidity.
TABLE V.-PERCENT WEEVILS LIVING IN A LOW TEMPERATURE INCUBATOR FOR
A SPECIFIED NUMBER OF DAYS AFTER THEIR REMOVAL FROM SEVEN HIBER-
NATION CAGES, RESPECTIVELY.
Percent weevils living in incubator after removal from hibernation cages
SCage Cage Cage Cage Cage Cage Cage
Date No. 1 No. 2 No. 3 No. 4 No. 5 No. 6 No. 7
Jan. 25 100.00 .. ...... ..... ...... -
Feb. 8 98.45 100.00 ............... ........ .....
Feb. 22 93.80 94.60 100.00 ..... ...... ...
Mar. 8 87.21 92.43 95.77 100.00 .......... ...... ......
Mar. 22 78.30 84.35 94.36 92.79 100.00 .......... ........
Apr. 5 66.70 80.00 84.18 86.76 91.67 100.00
Apr. 19 62.02 74.60 83.80 84.35 86.12 94.76 100.00
May 3 54.26 63.25 77.46 75.92 79.17 90.83 92.60
May 22 49.23 55.15 67.60 71.10 66.67 82.54 79.64
May 31 44.96 49.19 64.80 67.48 65.28 79.04 75.93
June 14 30.23 38.38 53.52 44.59 55.56 58.95 59.26
June 28 10.08 22.70 28.17 32.54 45.84 40.61 29.63
July 16 2.71 9.37 18.31 16.87 22.22 15.28 1.85
July 26 1.16 5.95 10.56 13.26 13.89 7.86 1.85
Aug. 9 0.00 1.08 1.41 3.62 4.17 3.49 0.00
Aug. 23 ........ 0.00 0.00 0.00 1.39 1.31 ..........
Aug. 29 .......... ........ .......... .......... 1.39 0.87 .
Sept. 5 .................... .......... 0.00 0.44 ...
Sept. 14 .......... ......... .......... ........ .......... 0.00 ..
The reliability of the data which are generally obtained from
hibernation cages, however, is so questionable that the general
use of cages as indicators of probable weevil distribution and
population is unwarranted.
"Grossman, Edgar F. Biology of the Mexican Cotton Boll Weevil VI.
Some Humidity and Temperature Effects on Development and Longevity.
The Florida Ent. Vol. XIV. No. 4, pp. 66-71. Dec. 1930.
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FLORIDA ENTOMOLOGIST
Official Organ of The Florida Entomological Society, Gainesville,
Florida.
Vol. XV, No. 2 August, 1931
J. R. W ATSON ........----.. ----............-............----- ........- ................-Editor
WILMON NEWELL --..............--------....................... -Associate Editor
H. E. BRATLEY..--........-..........---------- ..-.....-.--.....Business Manager
Issued once every three months. Free to all members of the
Society.
Subscription price to non-members is $1.00 per year in ad-
vance; 35 cents per copy.
A CONTRIBUTION TO THE LIFE HISTORY AND HABITS OF
THE CELERY LEAF TYER Phlyctaenia rubigalis GUENEE
IN FLORIDA
RALPH L. MILLER
ABSTRACT
The celery leaf tyer is commonly present in the celery grow-
ing areas of Florida and whenever it has a continuous supply of
food material for several months, when the population is not
reduced artificially and the meteorological conditions are fav-
orable, it becomes quite destructive. At Sanford, Florida, it
feeds on some seventy host plants, many of which are abundant
throughout the entire year.
The entire year can very easily be spent in the active stage
without any difficulty of feeding, dwarfing or sterility of adults.
The most favorable humidity for development and most rapid
reproduction was about 80%.
The celery leaf tyer or greenhouse leaf tyer, Phlyctaenia rubi-
galis Guenee, has done severe damage to celery in Florida for
many years. However, many points in its life history and de-
velopment, especially during the summer months, have been quite
obscure. The work of the writer on this subject, covering the
period from November 1, 1928 to May 1, 1929, full time, and part
time during the remainder of the year 1929, is reported in the
following paper. The work was done in the laboratory and field
at Sanford, Florida, in a station maintained jointly by the United
States Department of Agriculture, Bureau of Entomology, and
the State Plant Board of Florida. Occasional trips were made to
SUMMER NUMBER
the other celery growing areas in the state and studies of celery
tyer populations there were made. Many thanks are due the
fellow workers of the writer at Sanford, Florida, for their many
suggestions regarding the work.
DISTRIBUTION AND HOST PLANTS
The celery leaf tyer is generally distributed over the entire
celery growing area of the state of Florida. Its abundance
varies from such scarcity during the late summer that it cannot
be found, to more than two or three hundred adults per three
hundred foot row of celery during the late spring. When the
celery is cut during April or May, the adults leave and at that
time the larvae can be found on some sixty or seventy host
plants, as shown in Table II following. During the growing
season for celery, the moth population increases continuously
and abundantly, increasing more than 200 times during five
months, as shown in Table I.
TABLE I.-ABUNDANCE AND INCREASE OF CELERY LEAF TYER ADULTS DUR-
ING THE CELERY GROWING SEASON AT SANFORD, FLORIDA.
Number Number
Month of Rows Feet Per Row Moths Per Row
December (1928) 15 300 1
January (1929) 29 300 3
February 21 300 112.5
March 12 300 126.5
April 15 300 201.1
Where there is not a continuous supply of growing celery the
tyer cannot build up its population as shown above. In sweep-
ings at both Sarasota and Oviedo, where there is a break be-
tween the fall crop and spring crop of celery, not more than
twenty-five or thirty moths were found per row at any time,
while all other factors were similar.
When the celery is all cut in late spring the tyer migrates to
any succulent plants growing in a damp, cool, shaded place. It
it very abundant in the swamps, woods, ditch banks and similar
places. During the time when the celery fields are not irrigated
and before the summer rains begin, the celery tyer population
along the beaten paths becomes greatly reduced so that by June
15th almost none can be found. However, diligent search will
usually reveal a few that are left in the out of the way damp,
cool places down in the weeds or swamps.
Many writers have prepared long lists of plants on which
this insect will feed. The writer has a similar list composed
THE FLORIDA ENTOMOLOGIST
of plants on which celery tyer larvae were found feeding at
Sanford, Florida, during the year 1929, as shown in Table II.
TABLE II.-SEASONAL HOST PLANTS OF THE CELERY LEAF TYER AT SANFORD,
FLORIDA DURING THE YEAR 1929.
Celery
Spinach
Escarole
Corn
Cabbage
Parsley
Lettuce
Strawberry
Turnip
Chinese Cabbage
Japanese Pea
Barley
Beets
ORNAMENTALS
Calendula
Petunia
Snapdragon
Viola odorata
China Aster
Nasturtium
Carnation
Daisy
Sweet Pea
Poppy
Larkspur
S Strawflower
S Chrysanthemum
Zinnia
SGeranium
Corn Flower
Cosmos
Coleus
SI Marigold
SUMMER NUMBER
I I I I I I I I
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WEEDS
Spanish Needle (Bidens leu-
cantha)
Sow Thistle (Sonchus)
Amaranth (A. spinosus & A. re-
troflexus)
Cudweed (Gnaphalium)
Night Shade (Solanum nigrum)
Commelina communis
Chenopodium ambrosioides
Castor Bean
Parietaris floridana
Ragweed (Ambrosia bidentata)
Fireweed (Erectites)
Flebane (Erigeron vernus)
Stachys floridana
Pokeweed
Morning glory (Calonyction bo-
nanox)
Grass (Panicum sp.)
Dog Fennel (Eupatorium capill-
folium)
Eclipta alba
Plantain (P. major)
Plantain (P. lanceolata)
Bindweed (Convolvuls repens)
Specularia perfoliata
Senecio lobatus
Curly Dock (Rumex crispus)
Water Cress
Pennywort (Hydrocotyle)
False Nettle (Boehmeria cylin-
drica)
Portulaca oleracea
Dew-berry (Rubus villosus)
Crabgrass (Elusine indica)
Canna
Water Hemp (Acnida canna-
bina)
Lambs quarter (Chenopodium
alba)
Bishop Weed (Ptilimnium capi-
laceum)
Thistle
Shepard's Purse
THE FLORIDA ENTOMOLOGIST
LIFE HISTORY
After having established the fact that some seventy plants,
many of which grew abundantly during the summer months,
may serve as host to the celery tyer, it remained to show that the
celery tyer would actually live over the summer on these plants.
This was done very successfully and is shown in Table III fol-
lowing. Adults or eggs were placed on the plants and a thin
muslin bag was placed over that part of the plant. In this cloth
cage, the insects developed very abundantly. In a few instances
the bags were removed, sometimes accidentally, sometimes in-
tentionally, and in every case the celery tyer larvae finished their
development.
An interesting observation was that usually not more than
one generation could develop on one plant, for as soon as it
became injured by the larvae it became hard, tough and unfit for
feeding. For this reason, usually not more than one generation
was spent in one place, except on cultivated crops where develop-
ment was continuous. Since there are but few cultivated crops
that harbor celery tyer successfully during the summer months
and those on weeds only spend one generation in a place, the
difficulty of finding them through the summer is very great.
At Sanford, Florida, the celery tyer passed through nine first
born generations and seven last born generations during the
year December 1928 to December 1929. These were fed entirely
on celery and Bidens leucantha.
In all the life history work no difficulty was experienced where
the insects were given the proper food and care. All adults were
of normal size and the females deposited the normal number of
fertile eggs.
For details of the life history work see the following table.
TABLE III.-SUMMARY OF CELERY TYER LIFE HISTORY AND REARING DURING
THE YEAR DECEMBER, 1928 TO DECEMBER, 1929.
I I Days
Av. No. Av. Life Place of
Months Temp. Host Plants Reared Cycle Rearing
"F. | I
December 63.25 Celery ........................ .... 37 57.21 Insectary
& Spanish needle .............. 20 66.5 Insectary
January Bidens leucantha
January 65.85 Celery .................... .... 16 49.4 Insectary
& Amaranthus spinosus .... 17 49.0 Insectary
February Bidens leucantha ............. 12 50.4 Field
Sonchus sp. ........................ 1 55.0 Field
SUMMER NUMBER
Months
February
&
March
March
&
April
May
&
June
June
&
July
July
&
August
Av.
Temp.
F.
68.8
73.0
78.6
80.8
| 81.8
August 81.5
&
September
September 76.8
&
October
October 71.6
&
November
November 72.5
&Deembe
December
Host Plants
Celery ..--.............--.--.... ...
Fire weed -.. .......-....-----
Erechtites hieracifolia
Ragweed ......................---
I Ambrosia bidentata
Fleabane .....................
Erigeron vernus
Calendula ........................
Calendula officinalis
Celery ............................
Briad plantain ...............
SPlantago major
Bishop weed .....--..............
Ptilimnium capillaceum
Corn .................................
Zea mays
Dog fennel .....................
Eupatorium capillifolium
Celery ................................
Commelina communis ..-...
Water hemp .........-...
Acnida cannabina
Square weed .....-.............
Senecio lobatus
Celery ...................-..-......--
Chrysanthenum sp. .........
Cosm os ..................... ......
Bidens leucantha --..........
Mexican tea ....................
Chenopodium ambrosioder
SPlantago major ..............
Amaranthus spinosus ...
Celery ..............................
Cosmos .........................
M arigold .......................
Amaranth .........................
Mexican tea ..................
Commelina communis ...
Spanish needle .................
Violet (Viola sp.) .........
Cudweed .............-- ......
Gnaphalium sp.
Marigold .........................
Dog fennel .....................
Spanish needle .................
Marigold .. ...................
Spanish needle ...............-
Marigold ............. .........
Amaranth .....................
Celery ......................
M arigold .........................
Celery ...............--- ..-.......
I Days
No. Av. Life Place of
Rearedl Cycle Rearing
.12 51.6 Insectary
8 47.0 Insectary
12 44.0 Insectary
2 43.0 Insectary
. 15 45.0 Field
36.8
29.8
37.0
36.6
40.3
27.7
28.2
26.3
27.6
26.5
32.0
33.0
33.5
33.0
25.0
29.0
32.3
33.0
33.0
32.0
32.0
31.5
33.5
31.4
31.0
31.2
28.0
28.0
30.0
30.5
35.5
38.0
37.4
38.7
39.0
Insectary
Insectary
Insectary
Insectary
Insectary
Insectary
Insectary
Insectary
Insectary
Field-bag
Yard-open
Yard-bag
Yard-bag
Yard-bag
Field-
open
Field-bag
Field-bag
Yard-bag
Yard-bag
Field-bag
Field-bag
Field-bag
Field-bag
Yard-bag
Yard-bag
Yard-bag
Swamp-
bag
Yard-bag
Yard-bag
Yard-bag
Yard-bag
Yard-bag
IPorch-jar
IYard-bag
IPorch-jar
THE FLORIDA ENTOMOLOGIST
Another very important and interesting phase of the life his-
tory work was the effect of humidity on development, sex and
deposition of eggs. The humidities were controlled by aspirating
air through saturated salt solutions. The apparatus was set
up in a constant temperature room. Mr. C. 0. Bare corroborated
the writer's sex determination of the adults. The results are
shown in the following Table IV.
TABLE IV.-RELATION BETWEEN HUMIDITY AND DEVELOPMENT OF CELERY
LEAF TYER.
Av. Life II Av. No. eggs
% Humidity No. reared Cycle-Daysi % Male I % Female per female
I I
100% All died before emerging
80% 17 32.8 70.6 29.4 144.2
45% 9 33.1 44.5 55.5 35.0
25% 18 34.9 27.8 72.2 0.0
0 All died before pupation
The writer is quite aware that the small number of insects
used in the above experiment would tend to minimize the im-
portance of the findings, but since the results were so striking
it was thought advisable to at least make a progress report.
ATHENA PELEUS (Timetes petreus)
ELLEN ROBERTSON MILLER
In Florida a delightful phase of insect collecting is the fact
that one may come upon an unlocked for and occasionally a rare
specimen which by rights belongs in a more tropical country.
Such was my experience when on June 3, 1926 I found Athena
peleus (Timetes petrens Cramer) in its larval stage, feeding on
a fig leaf in my neighbor's yard. It was a caterpillar very dif-
ferent from any I had previously seen. Its length was one and
one-half inches and its body had the thickness of an old time
slate pencil. Its more striking characteristic was a dorsal pat-
tern of three light diamonds having an opalescent quality. They
began on the fifth segment and continued over the eleventh.
Dull orange-red tubercles each with a stiff black spine were at
the anterior and posterior points of the design, and also where
the diamonds joined, four in all. The skin at the base of the
tubercles had a bluish metallic sheen. This color in a paler shade,
was repeated between the diamonds and the darker triangular
side areas. These began at the front of the sixth segment. Each
SUMMER NUMBER
area showed a black line above and below a gray oval that was
outlined in iridescent blue. The second and third and fourth
segments each bore a dark oval, and there was a pair of black
dots on the dorsum of the first, second and third segments.
The bifurcated head was rough and of a dull red tone, a color
that extended back over the first four segments and appeared
in the prolegs. The long black spinuled antennae seemed to con-
tinue as raised lines on the face. The frons was sculptured with
parallel grooves and the adfrontales were conspicuous. It was
a colorful caterpillar.
I confined the larva with a spray of its food plant in a breed-
ing jar and on June 6 found it contracted to three fourths of an
inch, resting on the lid of the jar. The red color was gone from
its skin and the entire body appeared iridescent.
June 7 at 8:30 A.M. the larva was hanging by its anal claspers
to the silken mat on the lid which it had spun for the purpose.
At 9:30 a pale yellow-green pupa emerged.
The chrysalis had a pair of spines at the cephalic end and a
branched spine on either side of the thorax with other spines
following. Along the dorsum were three rows of black tuber-
cles, the middle row showing correct spines. The chrysalis had
a length of three-fourths of an inch.
I was away from home until June 20. Upon returning I found
that the butterfly had emerged and died. The specimen was
somewhat frayed but Doctor Kahl of the Carnegie Museum,
Pittsburg, identified it for me and kindly hunted out what little
had been written about the insect. He showed me the figures of
the larva and chrysalis made by Cramer which had been drawn
and colored by hand in 17-....., and also cases of pinned butter-
flies, one of which had been taken at Miami, Florida.
By one not conversant with the Lepidoptera the butterfly
might be mistaken easily for a swallowtail of the subfamily
Papilioninae. This because there are tails on each hind wing,
not alone the usual elongation of the Papilioes, but there is an
additional, shorter one.
Holland pictures the butterfly as on plate XXI of his Butter-
fly Book, showing the golden-brown upper surface of the wings
crossed by dark brown hands. It is very like my specimen. The
under surface of both body and wings is light, the latter show-
ing opalescent tones of blue, lavender, green and brown, a very
lovely play of color. A dark line edged with blue goes from the
body through the wing to the inner tail extension. Possibly a
THE FLORIDA ENTOMOLOGIST
butterfly clinging with closed wings to a twig simulates a leaf
and this mark suggests its midvein.
My specimen when spread measured two and one-half inches
from tip to tip of the fore wings. I have never seen the butter-
fly in the open, and have found but the one larva. The insect
belongs to the subfamily Nymphalinae.
KALO
NON-ARSENICAL INSECTICIDES
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KAOLITH. A fluorine spray, especially valu-
able for fruits, such as apples and
peaches. Recommended in Florida for celery and
tomatoes. A companion spray to Kalite dust. (Note.
Neither Kalite or Kaolith contains arsenic, lead or
copper. No arsenical residue)
KALOIL. A self spreading, free flowing pyre-
thrum contact spray. Needs no soap.
Special oxidized sulphonated oil spreader and acti-
INvator, increases efficiency and lowers cost. Gives
results in Florida when nicotine can not be used.
It will pay you to investigate. Ask the State Entomologists.
THE KALO COMPANY, Quincy, Illinois
Printing for All Purposes
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Pepper Printing Company
Gainesville, Florida
We recommend the goods advertised in The Florida Ento-
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