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_U. S. DEPARTMENT OF AGRICULTURE,
BUREAU OF | ENTOMOLOGY—BULLETIN No. 49.

L. O. HOWARD, Entomologist.

REPORT

ON THE

HABITS OF THE KELEP, OR GUATEMALAN
COTTON-BOLL-WEEVIL ANT.

By O. F. COOK,

Botanist in Charge of Investigations in Tropical Agriculture,
Bureau of Plant Industry.

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WASHINGTON:
GOVERNMENT PRINTING OFFICE.
1904.

an

BUREAU OF ENTOMOLOGY. .

- O. Howarp, Entomologist and Chief of Bureau. ‘ : =

C. L. Maruarr, in ate of experimental field work.
F. H. CxirrenpEn, in charge of breeding experiments.

A. D. Hopxrns, in charge of forest insect investigations. aig

W. D. Hunter, in charge of cotton boll weevil investigations.

‘FRANK BENTON, in charge of apicultural investigations.

F. M. Wesster, in charge of field-crop insect investigations.

A. L. QuAINTANCE, in charge of bollworm investigations.

EY A. Scuwarz, D. W. CoquiLuLeTtT, TH. ee Natian BANKS, Assistant

Entomologists.
R. 8. Cuirron, E. 8. G. Titus, F. C. Pratr, AvuGtst Brsce, OTTO HEIDEMANN, A N.
CaAuDELL, J. Kotinsxy, R. P. Currin, F: D. CoupEN, Assistants.

R. CG. Atrnouse, W. F. Tastet, Mary G. Cuampney, A. J. LEISTER, Sa PARTELLO,

T. A. Keener, Stenographers and Clerks.
Lizuian L. Howenstern, J. F. Strauss, Drafstmen.

G. H. Harris, W. E. Hivos, A. W. Morritt, Sprincer Goes, C. M. Wauxker, J. C.
CrawrorD, Jr., W. A. Hooxer, W. W. Yorsers, A. C. Morean, W. D. Prercs,
E. D. Sanperson, E. C. Sansporn, A. C. Lewis, A. F. Conrapr, H. A. Morgan,

S. E. McCienpon, i. S. HaArpy, R: C. Howsty,.A. W. Buckner, J..B. Gannerr,

engaged in cotton boll weevil investigations.

F. C. Bisnorr, C. T. Bruges, A. A. Grrautt, C. R. a ones, engaged in bollworm investi-
gations.

J. L. Wess, H. E. Burks, W. F. Fiske, engaged in forest insect investigations.

Lesuig Martin, J. M. Ranxin, engaged in apicultural investigations.

HENRIETTA A. eee C. J. Gituiss, W. A. KELEnER, Marte Rey, Maset F. CLASIONS

engaged in silk wnvestigations.

HERBERT OsporN, J. 8. Hinz, C. E. CoHamBuiss, LAWRENCE BRUNER, Tonporied Field

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Agents.

U. S. DEPARTMENT OF AGRICULTURE,
BUREAU OF ENTOMOLOGY—BULLETIN No. 49,

L. O. HOWARD, Entomologist.

OB Osa:

ON THE

HABITS OF THE KELEP, OR GUATEMALAN
COTTON-BOLL-WEEVIL ANT.

Bye O. Eo COOK,
Botanist in Charge of Investigations in Tropical Agriculture,
Bureau of Plant Industry.

WASHINGTON:
GOVERNMENT PRINTING OFFICE,
1904.

HABITS OF THE KELEP, OR GUATEMALAN COTTON-
BOLL-WEEVIL ANT.

The kelep“ was discovered.on the cotton April 20, 1904, in Alta
Vera Paz, Guatemala, and its efficiency as a destroyer of the Mexican
cotton boll weevil (Anthonomus grandis Boh.) was demonstrated the
following day. It was immediately appreciated, of course, that such
an insect would be of value in Texas, providing that it could be colo-
nized and would thrive in that State, and that it had no noxious habits.
To the solution of these questions all subsequent study of the species
has been directed.

Immediate practical use was also made of these observations of
habits and life history. The ant has been brought to Texas in healthy,
vigorous condition, notwithstanding injunction proceedings and other
unavoidable delays, which lengthened the period of travel and cap-
tivity to more than a month. Of about 4,000 ants, in 89 colonies,
scarcely more than a dozen died during the voyage, and half of these
were in a single colony which was for a time deprived of a queen.
The loss, too, was made good many times over by the emergence dur-
ing the voyage of numerous ants from pupe which had been collected
and placed in the cages with the mature insects.

While the adult worker ants expose themselves freely to dry air and
sunlight, the chief factor in the successful transportation of the colonies
has been the maintenance of adequate moisture in the cages by means
of artificial nests constructed of earth and stones, carefully built in to
form underground chambers not to be shaken down by the jarring
unavoidable in steamboat and railroad travel. It was fortunate,
perhaps, that the weevil ant was quite unknown when we left the
United States, for our outfit included nothing in the way of bell jars,
glass plates, and other laboratory appliances recommended by Lubbock
and other investigators of ants. Much time might have been wasted
with these complicated contrivances which would at best have been
far less suited to our purposes than the very simple means to which
necessity compelled a resort. For this ant, at least, the stone and

«This is the name of the cotton-protecting ant in the Kekchi language of Alta Vera
Paz, Guatemala. The word has no other meaning or derivation, but appears to have
come down from ancient times, when a higher agricultural civilization existed in this
region than that found by the Spaniards. The accent is on the second syllable, and
the first sounds as though written kay.

6

earth nests built at the bottom of glass jars, with the lower half pro-
tected from the light by closely wrapped thick paper, and closed above
by a piece of cloth, leave little to be desired. Many of the colonies
adopted the artificial nests without change, or have even carried out
the few particles of earth which accidentally fell in while the chambers
were being constructed for them. Others have brought in earth and
remodeled their apartments and are now living in chambers of practi-
cally the same size and shape as in their own nests. They have ceased
to be disturbed by the occasional removal of the paper cup from the
bottom of their cage, and all the operations of the colonies can be
observed under conditions altogether favorable.

It is not intended, however, to enter at this time upon detailed
accounts of the interesting domestic behavior of the ants, but rather
to give what might be called a biological outline of their activities,
from which it may be possible to understand something of their place
in nature and of. their probable utility in agriculture.

One of several minor agricultural virtues of these ants les in the
fact that they dig no large chambers or passages which can serye as
pitfalls for men or farm animals, as do many other kinds, including
the leaf-cutting ant of southern Texas, which the cotton planters are
attempting to exterminate at much expense. The nest of the kelep is
a simple burrow, extending from 1 to 3 feet into the ground, and con-
sists of from three to six small chambers, with connecting galleries.
The passageways are about a quarter of an inch in diameter and the
chambers from 1 to 3 inches broad and half or three-fourths of an inch
high, with level or slightly sloping floors and broadly arched roofs.
The queen, with some of the eggs and younger larvee, is generally to
be found in the lowest chamber, but the pupe in their cocoons are
usually near the top and the remainder of the smaller larvee and eges
lower down. In addition to the chambers inhabited by the ants there
are in each nest one or more cavities for the storage of the hard parts—
the bones, as it were—of the insects which the colony has captured
and eaten. Heads, legs, wings, and other fragments of insects of
many kinds, including the boll weevil, are here packed indiscrimi-
nately together. The mass is often penetrated by a network of deli-
cate roots, and is the home of several small animals which commonly
find shelter in the nests of the keleps: a snail, a worm, a mite, a Pod-
urid, and a thysanuran. A hymenopterous insect was also obtained,
which is probably a parasite of the ants.

The habit of preserving this useless débris is rendered the more
curious by the fact that dead ants seem not to be included in the col-
lection, but are carried out of the nest, as is the general custom
amone bees and other related insects. It was thought at one time
that some of the captive colonies were resorting to cannibalism, since
some dead ants were found pulled in pieces like the insects which had

7

been eaten, but this may have resulted from the prolonged efforts of
the living ants to carry the dead out of the nests. When the insects
were being liberated at Victoria after a month of captivity, almost
the first thing they did was to bring out their dead ants and carry
them as far from their nests as the boundaries of their inclosures
would permit.

The extremely slight mortality of the ants during the journey is an
evidence, certainly, of considerable hardiness. The unexpectedly
good result was probably due also, in a measure, to the fact that the
insects were transported during the rainy season when the atmos-
pheric humidity was high and the soil in the cages did not dry out
rapidly. The marginof safety is evidently a rather narrow one. If the
soil is too wet the insects forsake their chambers and crowd together
at the surface. When this was noticed the cloth covers were removed
to give more air and permit more rapid evaporation. Too great dry-
ness, however, is amuch more serious danger. Unless the color of
the soil be carefully watched the first intimation of difficulty is likely
to come in the form of dead ants. The danger could be lessened, of
course, by increasing the quantity of soil in the cages, but this would
have the disadvantage of additional bulk and weight, important con-
siderations where transportation is so difficult as in Guatemala.

It seemed possible when the first report was sent in, that the very
limited distribution of the ants might be due to some inability on
their part to dig in other than the very loose shale soil which covers
the particular slopes specially preferred by the insects, according to
the belief of the Indians. Later, however, the ants were found in _
somewhat different situations, and even on level bottom lands, though
such are very rare in that part of Guatemala. Considerable diver-
sity of soil was also revealed during the excavations made in cap-
turing the colonies brought to the United States. Furthermore,
another way was found of explaining why the ants have so limited
a range. It is only on these very loose soils that weeds can be
pulled easily, and hence it is only these which can be cleared without
burning. <A nearly continuous cultivation can be maintained, which
is very exceptional under Indian methods of agriculture. The cotton
is planted, too, during the latter half of October—a very rainy period
when burning is impracticable, so that the ants are not destroyed, as
must happen in the clearing of land for corn, beans, and other crops.
If these considerations have the supposed bearing, it is not impossi-
ble that in the United States, where the land is cultivated more con-
tinuously, the ants may multiply and extend their boundaries much
more rapidly than they have been able to do in Guatemala.

Every practicable effort was made in Guatemala to find the ants in
other localities more accessible than the remote and mountainous dis-
trict where they were first discovered and from which the caged insects

8

had to be brought out by Indian carriers.. None of the keleps were
found, however, in other parts of the country, and the probability of
their existence elsewhere seems smal] in view of the fact that-no other
field cultures of cotton exist in the neighboring regions, although the
natural conditions are generally favorable and many attempts have been
made, some ona very large scale. In a few instances a satisfactory
crop was obtained the first year before the weevils had time to multi-
ply, and expectations were aroused which only deepened the subse-
quent disappointment. One very small field of cotton in the Polochie
Valley, below Tucuru, was said to be 4 miles from any other plants,
but the weevils had found it before the crop ripened. There are
rumors of the existence, in Mexico, of tree cottons which are resistant
to the boll weevil, but in Guatemala these suffer quite as much as the
smaller kinds. Large trees often failed to furnish a single uninjured
boll as a specimen for our collection of varieties. The wish to find
the protecting insects nearer home has been echoed by many news-
paper accounts claiming the existence of the same or simiJarly useful
ants in various parts of Texas, but thus far none of these reports has
proved to be based on fact. The kelep is as yet the only ant known
to attack and destroy healthy adult boll weevils, just as the cotton
grown with the protection of the ants is, so far as known, the only
field culture permanently maintained in the weevil-infested regions of
Central America.

It was feared at first that the keleps would not be able to excavate
nests in other than very loose and granular soils, and particularly that
they might fail to penetrate hard and tenacious subsoils like those
which underlie some of the cotton fields about Victoria. Itseems, how-
ever, that these offer no special difficulties for the ants. Some of the
buried colonies are bringing up earth from a depth of about 18 inches,
and in experimental nests constructed of the tough Texas soil the ants
have given ocular demonstration of their power to dig out passage-
ways. The nest of a colony which has been in the ground at Victoria
for a week shows, on being dug out, a nearly vertical gallery, with a
depth of 14 inches, and the usual lateral chambers. Whether the ants
will survive the floods to which many of the level cotton lands of
Texas are subject, is one of the questions still to be answered. In
Guatemala they are accustomed to very heavy rains which thoroughly
saturate the soil, but the drainage is excellent. Possibly, however,
the impervious nature of some of the Texas subsoils may afford pro-
tection by holding air in the nests.

Another equally practical question is frequently asked by planters
who cal] to see the ants. Will not plowing and cultivation destroy
the nests and drive the insects from the cotton fields? As they
burrow to a depth of from 1 to 3 feet, the shallow plowing cus-
tomary in Texas will cut off only the passage leading to the surface,

9

and this the ants will undoubtedly be able to renew in a few hours.
No injury need be anticipated on this score, except the loss of the few
individuals actually stepped on and crushed. Where the surface soil
is loose the ants are careful to start their nests against some rigid
object, often at the base of the cotton plant itself, and follow the
root down 2 or 3 inches where a more moist and firm material can be
reached. The frequency with which this occurred in Guatemala may
indicate that the ants transfer their nests to the vicinity of the cotton
after it has begun to grow. There was no indication that the making
of the burrows injured the plants, but, if anything, the reverse; at
least the largest ant colonies were dug out where the cotton had flour-
ished best. Goner al reasoning would also suggest that the slight open-
ing of the soil about the plant would be as heel to benefit as to injure
it. Nothing was found to indicate that the roots of the cotton or any
other plant are attacked by the ants. They may gnaw off a small root
which interferes with their operations, but they disturb the soil so little
that such damage must certainly be extremely slight and in complete
contrast to the extensive injuries often done by the large red ants
(Pogonomyrmex barbatus) native in Texas, which permit nothing to
grow within an area of several square yar ae surrounding the entr ance
of their nest.

Like the human inhabitants of tropical countries, the ants have the
habit of taking a siesta. When the weather is clear and hot they are
much less numerous upon the cotton plants in the middle of the day
than in the morning or evening, and in the longer days and drier
climate of Victoria a tendency to lengthen this period of retirement
to the underground nest is already evident. That the strong sanlight
and heat are distasteful to the ants is easily proved by alternately
shading and exposing the entrance of the nest. The ants appear
promptly when there is shade and seek their subterranean shelter
when it is withdrawn. The fact that the ants are thus quiescent in
the middle of the day when, according to Messrs. Hunter and Hinds,
most of the weevil injuries are inflicted, might seem to interfere with
their utility. But apart from the poetic justice of having the weevil
caught in the act of damaging the cotton, all purposes would be served
as well or better if it were disposed of in the evening or the morning
before. It seemed in Guatemala that the weevils, as well as the ants,
were more numerous in the earlier and later hours of the day; at least
they were easier to find. In rainy or cloudy weather more ants remain
on the cotton during the day.

The cotton which they protect in Guatemala i is an annual variety.
The crop is harvested in May and the old plants pulled up to make
room for the development of peppers, which it is customary to plant
among the cotton, to ripen somewhat later. The ants very rarely

10

climb the pepper plants, but weevils were in a few instances found
roosting upon them—a safer place, apparently, than upon the cotton.

While most ant colonies have only one queen, several were found
with larger numbers, usually two or three, but in one case six and in
another fifteen. Queens occasionally retain one or both of their wings,
and when the colony with the fifteen queens was captured several of
them had wings, which were lost later. It was thought that these
queens might be young and unfertilized, but large numbers of eges
have been laid and these are now hatching. If the queens were unfer-
tilized the eges will doubtless, to judge from the analogy of bees and
other ants, produce males, which may be very desirable if it should
prove possible to breed the insects in captivity.

The queen does not have a special chamber, but walks about among
the workers. She was usually found in the lowest chamber of the
nest, with eggs and young larvee, and nearest to the ‘bone yard,”
but if the lower chambers of the nest were opened first by digging in
from the side, she sometimes took refuge in the upper rooms or per-
haps escaped into the open air. In several of the nests no queens
were found. In the cages the queens usually remain constantly in the
lowest chambers and are fed by the workers. Some queens seem,
however, to have more of the instincts of workers, and one or two
regularly come to the surface to feed with them. In one instance a
worker was seen carrying a queen about the nest. She had been
seized by the jaws and her body was waving in the air over the
worker’s back. It was feared at first that she was dead, but on being
released her actions were normal.

At Victoria some of the colonies were released by placing the jar on
the ground and inserting a bent cotton stalk on which the insects could
climb out. They immediately began digging a burrow at the base of
the adjacent cotton plant, and in the course of two hours the workers
were ready for the queen and a delegation of two or three of them
brought her out. She returned several times to the underground
chambers of the cage, but was finally aroused sufficiently to follow
along the cotton stalk and out of the jar. The eges and larve had
already been removed. One of the queens did not go directly into
the ground, but climbed the cotton plant and remained there about an
hour, in spite of many visits from workers who caressed her with their
antennze as though to coax her to come down. In some instances the
queen remained longer in the old nest and was not transferred till
night, when the colonies seem to be quite as active as in the daytime,
perhaps more so. On another occasion the queen was carried bodily
into the new nest by a worker who seized her by the mandibles, as
mentioned above. . ;

The very strong homing instinct of the ants would have made it
safe to release them in the plantations for study, even if their other

TT

habits had been less known. Instead of scattering or becoming bewil-
dered -under the strange conditions they act from the first as though
they were thoroughly familiar with their surroundings. Many colo-
nies have been tested on a table isolated below by water. The insects
were allowed to climb out of their cages by means of a ladder consist-
ing of a cotton leaf with the stem bent back. There was no hesitation
or preliminary exploration. The ants filed out at once and spread
themselves over the table. Weevils were often caught, stung, and
carried back to the cage within a minute or two after the release of
the ants from their captivity.

All observations continue to confirm the previous report, that this — ~
ant is a truly predaceous insect. Compared with the nervous haste
of many other species, its motions are slow and deliberate, and, like
the so-called praying mantis, it stands for long periods quite motion-
less, with its antennee and mandibles extended, ready for something
to come that way and be caught. It seldoms attacks weevils or other
insects unless they are in motion and a weevil is generally safe as lone
as it keeps quite still. The ant’s field of vision seems limited to less
than an inch. This, however, is adequate for practical purposes, since
the most convenient time for catching the weevil is when it is climbing
up the plant. In Guatemala a weevil placed on a leaf stem so as to
walk up and meet an ant was almost sure to be taken. In that coun-
try, however, weevils are seldom or never seen crawling about on the
cotton, perhaps because the ants have discouraged this habit; but Mr.
Hunter informs me that in Texas the weevils frequently reach the
bolls by climbing up from the ground, and that they usually pass
along the stems from one square or boll to another, so that the oppor-
tunities of the ants are excellent.

That the ants know how to sting the weevils at the only two points
where their armor is vulnerable shows, of course, a highly specialized
instinct, and it is altogether likely that all individuals do not possess
it in an equal degree. Some colonies, too, attack the weevils much
more promptly and skillfully than others. As might naturally be
expected, hunger increases the eagerness and adroitness of the insects,
and it seems, too, that the members of the large colonies show more
ferocity than those of the small, as is known to be the case with the
honey bee and many other social animals. The imported colonies
contain from twenty to one hundred and ten workers each, averaging
between forty and fifty. It may be that the smaller communities and
their queens would survive in captivity as long or longer than the
larger colonies, but if it should appear that they are less able to forage
successfully the desired increase in numbers may be much slower, so
that the use of larger cages and the bringing of larger colonies may
prove desirable, should further importations of the ants be made.
The rate of propagation of the keleps is likely to prove much slower

12

than that of the weevils, but the ants are such long-lived insects that
they may be expected to overtake the weevils under favorable con-
ditions. An ant queen has been known to live for fifteen years and a
worker for six years. 3

The fact that the ants attack, paralyze, and destroy the weevils has
been assumed frequently to mean that a battle takes place between the
insects, and pictures of such imaginary encounters have appeared in
the newspapers. As a matter of fact, however, the weevil has no
means of defense except its armor and is quite at the merey of any
ant strong and skillful enough to sting it. Even this stinging is not
always necessary, some weevils being carried into the nest without
being stung, and perhaps while still feigning death to avoid discovery.
The ants are strong enough to pull the weevils in pieces, but the pre-
liminary sting facilitates matters by preventing any further efforts at
escape. It is a well-known fact that insects and spiders which have
been stung and paralyzed by predaceous wasps as food for their young
will keep for considerable periods. The ants may utilize this means
of storing food when there is an overabundance; a colony fed for the
last three days exclusively on weevils kills more than it consumes, and
piles up the victims.

The fact that the ant uses its sting in capturing its prey has led
some to confuse it with the stinging ants which are serious pests in
some tropical countries. Some of these inflict painful injuries and are
much feared. There is, for example, an ant which makes nests among
the leaves of the coffee trees in Liberia, rendering it quite impracticable
to gather the crop until the insects are dislodged by fire. The kelep
does not belong, however, to any such category. It is a predaceous
or hunting ant which very seldom stings except to paralyze its prey
and thus render the game easier to capture and carry off; but at other
times it has no inclination to sting and does so only when actually
seized cr injured. The sting, however, is too small and weak to pene-
trate the skin of the inside of the hand, so that the insects can be picked
up with entire impunity. If accidentally squeezed between the fingers
or caught under one’s collar, a kelep may be able to sting, but the
wound smarts, in most people, for only a few minutes, and is on the
whole a less formidable injury than a mosquito bite, since the irritation
is less prolonged.

It should be a sufficient testimony to the peaceable temper of the
ants to state that in opening about 100 nests and collecting some 4,000
ants Mr. Doyle and I were stung only about half a dozen times, and
that with no care or precautions. A majority of the ants were picked
up with the bare hands while the disturbed insects crawled at liberty
over us. Under such circumstances a stinging ant would attempt
to wound any foreign object which came in its way, but the keleps
have apparently no tendency to defend their nest in this manner.

ail el

13

They are not afraid to climb upon the hand if one stands still, but they
appear to do this out of curiosity, and not to fight; and, as already
stated, they never attempt to sting human beings unless actually held
or injured. The fear that they may interfere with the cultivation
of the cotton or with the harvesting of the crop is entirely ground-
less. It would be much more nearly correct to compare them with a
harmless insect-eating animal like the toad than with the vegetable-
feeding, stinging ants, like the large red ant so common about Victoria.
This latter species has a vicious temper, seeks actively to sting the
intruder, and is able to inflict a serious, painful wound, accompanied
by nausea, headache, fever, and even temporary paralysis. Fortu-
nately, the cotton ant is able, by its superior dexterity, to defend
itself, and is always victorious in a struggle with the harmful Texan
species, the extermination of which would be almost as welcome at
Victoria as the destruction of the boll weevil itself.

The Indians believe that the keleps are able to combat also the
dreaded teken or leaf-cutting ants which are as serious pests in Guate-
mala as in southern Texas. It is scarcely to be supposed, perhaps,
that they can drive out well-established communities of the leaf-cutters,
but they may prevent the growth of new colonies by killing the
workers as fast as they appear above ground. At least there are no
nests of leaf-cutters in the areas occupied by the keleps.

The fact that the ants were fed on sugar during the journey from
Guatemala to Texas has suggested to some planters that the insects
may escape from the cotton plants and attack cane. This apprehen-
sion is also quite unnecessary. The moistened sugar was used merely
as the most readily obtainable substitute for the nectar secreted for
the ants by the cotton plant. The ant’s jaws are especially adapted
for catching the weevils or other insects, but are quite unsuited for
enawing into sugar cane or other vegetable tissues. They are too
long, blunt, and weak to be effective for biting, and are used only for
seizing, carrying, and pulling apart their prey. They do not crush
nor chew their food, and are apparently unable to eat anything except
liquids or substances soft enough to be lapped up, as it were, by their
tongues. While the insects are feeding, their jaws are usually opened
wide as though to get them out of the way. The strong front legs
are used in much the same manner as the squirrel’s paws, to assist the
jaws in grasping and turning the prey, though they serve also for
walking.

None of the numerous varieties of cotton growing at Victoria has
nectaries equal in size to those of the Guatemalan cotton protected by
the ants, but the quantity of liquid food available in fields of such
varieties as King and Parker may prove sufficient, the average size of
cotton plants in Texas being much larger than in Guatemala. More

14

ants will be necessary, however, for their protection, and the nectar-

producing qualities of the different varieties may become « question

of practical importance if the keleps should become established. At
present the nectar secreted on the leaves and ‘‘squares” of the cotton
goes to waste, or even serves to attract injurious insects, among them
the bollworm moth. The discovery of the ant supplies a practical
reason for the existence of the nectaries, hitherto quite unsuspected,
and it suggests the further possibility that the weevil and the ant may
have been factors in the evolution of the cotton plant, for the weevil
is not known to feed on any plant except cotton.

The former report alludes to the scarcity of insects in the cotton
fields protected by the keleps, but it had not at that time been ascer-
tained that these ants were a cause of the deficiency. The finding of
the bone yards filled with the disjointed remains of their prey proves
that they capture and consume adult insects of many and diverse kinds,
and at Victoria they have shown a taste for bollworms also and similar
soft-bodied larve. Their appetites are not, however, without dis-
crimination. They have spared, for example, the larve of ladybirds,
which are beneficial insects; also those of the small Thecla butterfly,
which is sometimes injurious to cotton. The former are often picked
up by the keleps but are put down again without injury, while the
latter are fondled and licked with the tongue. The keleps sometimes
visit plant-lice and leaf-hoppers to secure honeydew, but they have
not been detected in taking care of these insects or in carrying them
about, as do many other ants. This is the only suggestion of an unde-
sirable propensity on the part of the keleps, but the danger, if any, is
extremely remote—much less, indeed, than with many ants native in
the United States.

SUMMARY.

The present status of the investigation of the boll-weevil ant may be
summarized by saying that three of five crucial questions have been
met and answered, and that two others are still to be reached, but with
no insurmountable obstacles as yet in sight.

(1) An ant has been discovered in Guatemala which attacks and kills
the adult boll weevil, and thus holds this most injurious insect in check
and permits the regular harvesting of a crop of cotton, even under con-
ditions favorable to the weevil.

(2) This ant is carnivorous and predaceous; if injures no form of veg-
etation, and takes nothing from the cotton plant except the nectar secreted
for it on the leaves and floral envelopes. —

(3) The habits and temperament of the insect are such that it is readily
capable of domestication, transportation, and colonization in the cotton
fields of Texas.

15

The issues which remain to be determined are:

(4) Whether the keleps will survive the winter climate of Texas; and,

(5) Whether they can be obtained or propagated in sufficient numbers
to serve the practical purpose for which they have been introduced.

It would be most unfortunate, however, if the discovery of what may
prove to be an effective enemy of the boll weevil should result in any
premature relaxation of efforts to avoid damage by cultural expedients.
Indeed, it seems quite possible that the first use of the ant may be to
render such measures more effective, since while still limited to small
areas the keleps may be able to perform an important service if they can

still further reduce the number of weevils which survive the winter. If

the cotton plants close about the nests of the ants were allowed to remain
through the winter, the weevils would congregate upon them and thus
furnish the food which the ants are likely to require on warm days of the
colder months.

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