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1903.— No. 11.

Department of the interior.

BUREAU OF GOVERNMENT LABORATORIES.

BIOLOGICAL LABORATORY.

ENTOMOLOGICAL DIVISION.
BULLETIN No. 1.

PRELiiNAM BOLLEll ON INSECTS OF THE CACAO.

PREPARED ESPECIALLY FOR TITE BENEFIT OF FARMERS.

By CHARLES S. BANKS,

Entomologist, Bureau Government Laboratories.

MANILA :

BUREAU OF PUBLIC PRINTING.
10852 1904.

FRONTISPIECE.

[Drawn from nature, by Charles S. Banks, 1903.]
LEGEND.

Fig. 1. Cacao pod, showing mealy-bug, natural size, and the attendant ants and sheds built
by the latter,

2. Female mealy-bug and young, enlarged four diameters.

3. Egg about to hatch, enlarged forty diameters.

4. Young insect just hatched, showing filamentous mouth-parts, enlarged one hundred

diameters.

5. Female mealy-bug, enlarged nineteen diameters.

6. Male mealy-bug, adult, enlarged twenty-one diameters.

7. Ant, attendant to the mealy-bug, enlarged nineteen diameters.

8. Hymenopterous parasite of the mealy-bug, enlarged nineteen diameters.

1903.— No. 11.

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Department of the interior

BUREAU OF GOVERNMENT LABORATORIES.

BIOLOGICAL LABORATORY.

ENTOMOLOGICAL DIVISION.
BULLETIN No. 1.

PRELIMINAM BULLETIN ON INSECTS OF THE CACAO.

PREPARED ESPECIALLY FOR THE BENEFIT OF FARMERS.

By CHARLES S. BANKS,

Entomologist, Bureau Government Laboratories,

MANILA :

BUREAU OF PUBLIC PRIxVriNG.
10852 1904.

SB

^

LETTER OF TRANSMITTAL.

Department of the Inteiuoh^
Bureau op Government Laboratories,
Office of the Superintendent of Laboratories,

Manila, P. I., September IJf, 1903.
Sir: I have the honor to transmit herewith '^A Preliminary
Bulletin on Insects of the Cacao/^ by Mr. Charles S. Banks, Ento-
mologist, Bureau of Government Laboratories.
I am, very respectfully,

Paul C. Freer,
Superintendent Government Laboratories.
Hon. James F. Smith,

Acting Secretary of the Interior, Manila, P. I.

3

ILLUSTEATIOI^S.

Cacao mealy bug Frontispiece.

Facing page.

Fig. 1. a, h, c, Black ant, larva, and pupa 9

2. Wood attacked by white ants 10

3. Cicada, adult 10

4. Cicada, wing venation 10

5. Cicada, egg-laying apparatus (ovijwsitor) 11

6. Cicada, nearly f ull-gro wn ny ni ph : 11

7. Cicada, forefoot of nymph 11

8. Cicada, appearance of twigs after oviposition (from U. S. Dept.

of Agr. Div. Ent., Bui. 14, n. s.) 14

9. Cicada, old wounds in tree after one year 14

10. Anomala, species related to that on cacao 17

11. Anomala, larvj^e of species found on cacao 17

12. Anomala, larva in pupal cell 17

13. Cerambycid, adult 19

14. Cerambycid, larva 19

15-17. Branches killed by Cerambycid larvae 20

18. 18a, h, Cerambycid, burrows of larvc^e in wood 21

19. Bag used to protect the upper parts of the tree 23

20. Bags for the jirotection of the lower part of the tree 23

21. Termite, adult female distended with eggf:^ 25

22. Termite before distention with eggs, much enlarged 25

23. Termite, cells in which the young are reared 25

24. Termite, cross section of the queen cell 25

25. Psocidfe clustered on the trunk of the cacao tree and indi-

vidual Psocids 26

26. Twig girdler, w-ork on twig 26 mm. in diameter, enlarged 27

26a. Tw'ig girdler, work on twig 13 fnm. in diameter, redu(;ed 27

27. Orthopteron, work on branches, showing scar 27

28. Orthopteron, work on branches, showing eggshells in place 27

29. Orthopteron, small scar with eggs 28

30. Plant lice, stages from larva to adult 29

3 1 . Plant lice, f ru it d istor ted by 11 ce 30

32. Thrips, leaves curk^d by the insect in its attacks 30

33. Thrips, adults enlarged 30

34. Large yellow scale, adult enlarged and eggs at J) 31

35. Sphindidfie, adult, showing markings of wing covers, enlarged- 31

36. Eucleida?, full-grown larva 33

37. Eucleidc% pupa 33

38. Slug caterpillar, damage to leaves 34

5

6

Facing page

Fig. 39. Slug caterpilJar, larva 35

40. Slug caterpillar, cocoon from which the adult has escaped __ . 35

41. Shig caterpillar, another form, larva and parasite 85

42. Slug caterpillar, another form, work on leaves 35

43. ChrysomelidjK, full-grown beetles 36

44. Chrysomelidpe, larva of related species (redrawn from Com-

stock) 42 '

45. Sisi scale insect, showing the insect on the leaf and enlarged- 42

46. AliiTgayo, adult and larva and j)upa 42

47. Nest of aliiigayo 42

48. A momo-ong, adult 43

49. Nestof araomo-ong » 43

50. Red corsair 44

51. Ant-lion, two views of nest 46

51a. Ant-lion, two views of larva 46

52. Praying mantis, eggmass 47

53. Praying mantis, young 47

54. Praying mantis, adult 47

55. Orb w^eaver spider, crescent variety 48

56. Jumping spider and ant-like form 48

57. Cacao pods attacked by rats 49

58. Cacao leaf spot . 52

59. Cacao pod fungus, sx)otted form 52

60. Cacao pod fungus, blight form 52

A PRELIMINARY BULLETIN ON INSECTS OF THE CACAO, PREPARED ESPE-
CIALLY FOR THE BENEFIT OF FARMERS.

By Charles S. Banks,
Entomologist, Bureau of Government Laboratories.

This bulletin is prepared particularly with a view to its practical
value to the farmers of the Philippines in the cultivation and pro-
tection of an industry which promises much in the future for these
Islands.

As this bulletin is the result of only three months actual investi-
gation of cacao insects^ it does not in any way cover all the insects
which are directly or indirectly associated with the growing of
cacao.

Much has yet to be learned of the habits and life-histories of
many of the iuvsects treated herein, owing to the fact that the
periods of their transformation extend over a year or more. The
publication of the material at this time is in response to an urgent
demand upon the part of growers for information that will help
them in combating the more serious pests.

All the illustrations, where not otherwise credited, are from pho-
tographs made by myself or by the Government photographer under
my direction, or are from original draw^ings made by myself or
under my supervision b}^ Juan de Guzman and Jose Garcia.

The frontispiece was drawn by me from nature, partly in the
field and partly from material brought back from my trip.

I wish to acknowledge my personal thanks to Sr. Don Juan A.
Araneta, of the hacienda ^^Louisiana,^^ Maao, Occidental ISTegros,
for the many ways in which he aided me in the work of investiga-
tion which I carried on upon his plantations.

C. S. B.

Manila, P. I., August 28, 190S.

7

CACAO INSECTS.

Up to the present time^ so far as search has revealed^ very little
has been published upon the subject of economic entomology in
the Philippine Islands. In the several admirable works on the
entomology of the Archipelago^ we find not only that the economic
side has been entirely neglected, but also that the same thing is
true from the biological standpoint. The only attempts made in
the past have been to determine the names of specimens, in most
cases collected by one man and classified by others. For even the
most common species of insects^ few or no data are given regarding
their habits, life-history, or relative abundance at certain periods of
the year or in stated localities.

In preparing this brief preliminary bulletin on the insects of
the cacao, I realize that I am but hinting at some of the more im-
portant pests which have been encountered during a comparatively
short period of the year; so that all the conditions as they would
occur consecutively during the course of twelve months, and un-
doubtedly changing slightly with each succeeding year, are not now
noted, nor are all the subjects mentioned treated exhaustively, the
object being at the present time only to set forth as clearly as
possible some of the most common and more destructive insects,
with practical suggestions for the prevention or treatment of their
ravages. At the same time it is proposed to mention a few of those
insects, which, because of their predatory habits in feeding upon the
injurious forms, should be considered as beneficial to the farmer.

Perhaps one of the most valuable crops produced in the Phil-
ippine Islands in proportion to the quantity raised, is the cacao
bean, the product of a tree of the family Stercidiacece and botan-
ically known as Theohroma cacao. The tree averages from 4 to 12
meters in height, and, as grown in these Islands, usually assumes
a somewhat oval form in its mode of branching, like the pear tree
of the United States.

Like nearly all other plants, when brought into cultivation, it is
subject to many diseases and the attacks of a large number of
8

OF*

9

insects. This is more or less true in all parts of the world where
it is grown^ in Venezuela^ Trinidad^ Java^ and particularly, it
would seem, in the Philippines.

In this bulletin some of the injurious forms of insects will be
mentioned, together with what has been learned of their life his-
tories up to the present time. As it is very necessary to know the
most susceptible stage of an insect^s life in order to know what is
the easiest remedy to apply to it, we can readily see the necessity for
becoming familiar with its life-history. It is hoped that further
observations will enable me to treat the subject more exhaustively at
a future time.

In suggesting remedies, those are given which have been found
most effectual for similar pests in the United States, but the
effort has been made to so modify them as to make them fit local
conditions.

For convenience, the subject has been divided according to the
part of the plant attacked. Thus, beginning with the roots, we
will in order discuss the insects of every part of the tree, giving
their habits and mentioning the best means to be used against them.

INSECTS ATTACKING THE ROOTS.

BLACK ANTS.

Tlie principal insects at present known to attack the roots are a
species of large, ferocious ant, a species of Cicada, and the grub of a
beetle belonging to the genus Anomala, but not yet identified.

The ants are black and are characterized by the ability to inflict
a very severe sting. The abdomen is constricted between the first
and second segments,, the first segment having two backward-
pointing spines on the upper part. The head, thorax, and first and
second abdominal segments are beautifully corrugated. The legs
and antennae or feelers are very long. The light-brown cocoons,
made of a silk paper, are usually very abundant in the nests, which
are located at the base of the #tree among the larger roots. Within
these cocoons may be found the white grubs, which are shaped very
much like a long-necked gourd, the head being at the smaller end.
(See fig. 1 6*.) The larvae or grubs, before spinning their
cocoon, and the eggs are simply deposited by the workers in any
convenient part of the nest. The adults are the only injurious
forms of these insects. They gnaw the bark from the large roots,

10

thus inviting decay^ and making an opening for the entrance of
the insidious white ant, another very serious enemy of the cacao,
belonging to the genus Termes. The latter is called anay in
Visayan and Tagalog, and is probably the most serious insect pest
in the Philippines, destroying, as it does, nearly every conceivable
class of material except articles made of metal. It has hitherto been
supposed to attack only woods which had been previously cut, but
in the work of investigation on cacao insects it has been conclusively
proven that it also attacks the living tree, at least in the case of
cacao. (See fig. 2.)

In the United States the members of the genus Cicada are
restricted to not more than five species. In the Philippines there
are several, some being large and black and others grey, while still
another species is of a very light yellowish green. A singular
thing about the individuals of the genus is that the males give
forth a strident noise, produced by means of two drum-like organs
on the lower side of the first segment of the abdomen. Unlike the
members of this genus in America and Europe, which generally
"sing^' in the hottest days of summer, the individuals found in
the Philippines almost invariably reserve their serenade till the
falling of darkness, when their strident notes may be heard on
every hand, especially near wooded lands.

All observations thus far made upon this interesting insect would
lead me to infer that the habits and life history are the sauie in
the Philippine Islands as in other parts of the world, particularly
so in the case of the dog-day cicada in the United States.

Here the species may be found at all times, and the insects are
so common as to be used as playthings by the native children, who
capture them to make then sing. In Visayan they are called
''Ceriritan'' and in Tagalog ''Culiclicf

The adult of the species which attacks the cacao tree measures
42 mm. to the tip of the wings, which project 13 mm. bej^ond the
tip of the abdomen. The body is robust, somewhat conical, and
is composed of a series of very regular segments, which may be
more easily distinguished on the abdomen than on the thorax.
(See fig. 3.) The insect has four very beautifully marked, trans-
parent wings, the fore ones being much larger than the hind. The
venation is shown in ^g. 4. When at rest the insect^s wings are
laid over the abdomen, roof -like. The Cicada has a swift but
erratic flight. This is due to the lack of coordination between the

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Fig. 4.

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Fig. 6, Fig. 6 ;

11

wing muscles of the opposite sides of the body. By holding the
insect between the thumb and the forefinger^ so that the wings are
free to move^ it will be seen that the opposite pairs move alter-
nately.

The insects of this genus pass through a very remarkable series
of changes from the egg to the adult stage. The total duration of
the metamorphosis has not yet been determined^ but it is safe to
estimate that in this region the time occupied is not less than
eighteen months. In America one species nearly related to this
lives from thirteen to seventeen years in the ground before reaching
maturity^ while another completes its transformation in two years.

The female Cicada is provided with a very peculiar ovipositor or
egg-laying apparatus (fig. 5), by means of which she slits the twigs
of young branches of the cacao. Inasmuch as the wood of the-
cacao is comparatively soft, she finds no great difficulty in placing
her eggs in branches which are larger than those ordinarily found
with Cicada eggs in tlie United States. Within from four to six-
weeks from, the time the eggs are laid, the young hatch. They
are tiny white creatures which resemble very mucli the full-grown
nymph, except in size. Their forefeet are adapted for digging in
the ground, and they, dropping from the twigs, begin immediately
to burrow down to the tender rootlets of the plant, where they
settle and insert their beaks for sucking the Juices of the roots.
Fig. 6 shows the nearly full-grown nymph, and i\g. 7 sliows its
forefoot. The larva or nymph forms a dirt cell around the spot
where it decides to remain. This it does with its forefeet, using
them as a mole would, and packing the earth at tlu^ rear and above
it with its other legs. Thus is made a subterranean cavity where
this little enemy of the roots of the cacao may live and feed.

The mouth of the insect is of the sucking class — that is, the
v^arious parts are modified to form a lancet for piercing the epi-
dermis of the plant upon which it feeds, and a tube-like structure
through which the sap is drawn up into the mouth cavity, whence
it is conveyed to the stomach.

When very young, the larvae may be found not more than
10 or 12 cm. below the surface of the ground, but as they grow
larger they gradually work their way downward. In some cacao
trees they have been found as deep as 80 cm. below the surface,
clinging tenaciously to the roots by their beaks and their legs.

12

They are not at all able to defend themselves^ nor to escape from
any kind of enemy which might come upon them.

These insects do not change their form to a very marked degree
in passing from the larval to the pupal and the adult stages^
as do butterflies^ beetles^ and flies. Just previous^ however^ to
their assuming the adult form^ there appear tiny wing pads on
the sides and within these are the wings in embryo. These pads
appear in the second moult previous to the adult stage. (See fig. 6^
which shows the wing pads lapping back upon the abdomen.)

When the insect is ready to assume its final or winged form it
comes up out of the ground^ leaving a tunnel behind^ which may
often be found when digging out trees. These tunnels are some-
times partitioned off and used as nests by a certain species of
small tarantula^ which will be mentioned below.

Upon reaching the surface of the ground the pupa of the Cicada
climbs to some convenient place^ usually the trunk of the cacao
tree or the small scions which spring up around the parent tree,
and there it clings, awaiting the final change, which consists in the
bursting of the pupal skin and the emerging of the adult insect.
This takes place as follows : The skin of the pupa splits longitudi-
nally on the back, from between the eyes to the posterior edge of
the thorax. The insect within this shell begins a forward
wriggling motion and soon the head is free from the casing. The
forelegs, which in the larval and pupal stages are much-shortened
hooked claws, come forth from the pupal case, long, slender, and
fitted for walking instead of digging. The insect grasps some pro-
jecting point upon the bark where it is resting, with these yet feeble
claws, and thus is aided in its exit. The second pair of legs soon
come forth, then the wings, which are very much doubled up and
are very soft, are drawn out from the shell. At this stage the
animal rests a while, apparently nearly exhausted. When it has
thus rested, the insect makes its final attempt and the hind legs and
abdomen are withdrawn. It now simply remains upon the tree, and
the doubled and delicate wings begin to expand until they have
reached their full length. It is supposed that this expansion is due
to air pressure within the body. They are now very thin, of a
beautiful translucence and very soft, so that the least breeze causes
their fluttering. The body of the insect is also very soft and may
be easily crushed. It is of a very pale, pinkish color, but soon
turns grey, evidently owing to the action of the sunlight, all the

13

characteristic markings coming out upon its surface. Within an
hour, seldom less, the insect begins to move its wings as if testing
them, and now the slightest movement on the part of the observer
will cause it to quickly take wing, giving a short clicking sound as
it flies away. If the insect be a male, it at once makes its char-
acteristic ''creet,^^ a noise familiar to all, as it starts to fly. If it be
a female, it remains in silence. It is not definitely known how
long a period elapses from the emergence of the insect from the
ground, until it mates and begins the work of laying its eggs.
Further observations will be necessary to determine this.

The principal injury to the cacao from these insects consists in
the lacerating of the young wood by the females in placing their
eggs, and in the damage done to the tender rootlets by the larvae
and pupge. The former not only debilitates the tree from the me-
chanical injury, but also opens a path by which other injurious
insects may enter the tree to do their damage. This is no incon-
siderable feature of their harm, especially when they attack the
larger twigs and stems, because it is more frequently upon the
larger stems that Scolytids, Ceramdycids, and other beetles do their
work.

When fifty or more of the larva? attack the young roots and
rootlets, the principal food-getting organs of the tree, they not
only use up the moisture which the roots have already taken up,
but they likewise so mutilate and debilitate the latter as to impair
the functions of moisture gathering. Of the several cacao trees
which the writer dug up, none were more than 5 m. higli and in
no case did their roots extend more than 95 cm. below the ground
surface, and as the pupse of Cicada were found as low as 80 cm.
it can be readily seen that they command practically the whole of
the root area.

In the matter of combating these insects, several methods sug-
gest themselves. As it is practically impossible in a large planta-
tion to use preventive measures entirely, those means which also
look to the extermination of the already established pests must
be used.

The pupae, when emerging from their ground retreats, are
entirely helpless, and they, as well as the newly transformed adults,
are easily captured upon the daily visits to all the trees by the
watchers and workers in charge; in fact this could very easily be
done by children, who seem particularly expert in capturing the in-

14

sects which the}^ like to make "sing/' Even the full-fledged adults
of several days may be captured upon the trees at dusk, when the
males begin their concerts and the females are close by to listen.
During midday the insects may sometimes be caught upon the tree
trunks, but are more wary and harder to take.

Certain species of birds are known to be enemies of the Cicada,
at least in the Island of ^egros. Eepeatedly the writer, when in
the cacao plantations, has heard the uneasy creet of the Cicada,
and following with his eye the direction of the sound, has seen a
bird carrying off the insect. The species could not be ascertained,
but from its general size and form, it undoubtedly belonged to the
Shrikes or Laniidae. This should lead the grower to carefully
protect all birds which have the inclination to visit or live in the
plantation of cacao, as being beneficial, not only in the destruction
of the Cicada, but also in ridding the trees of other injurious
insects like scale-insects, mealy-bugs, and caterpillars of various
species.

If the insects are captured upon emerging they will have no
opportunity to lay their eggs, but as this can not be done in all
cases, a close daily survey of the trees at the time when the adults
of Cicada are beginning to be numerous will reveal the work which
they do on the twigs. The characteristic appearance of the twigs
after eggs have been deposited in them is shown in Rg. 8. It was
claimed a number of years ago that the Cicada only deposits her
eggs in dead twigs, but observation has since proven that this is
not the case, she invariably choosing live wood for this purpose.
The short time during which the eggs remain in the slit would
not be sufficient for the growth to crush them, and moreover, the
growth of a twig which has been lacerated by the ovipositor of the
Cicada is away from the wound, causing the latter to gape within
a year from its formation, as shown in fig. 9. If these twigs are
carefully removed by means of a very sharp knife, and if they are
afterwards destroyed by burning, while the eggs are yet unhatched,
much can be done to lessen the number of Cicada attacking the
trees.

If a twig, into which eggs have been newly laid, be examined by
cutting it open longitudinally, the white eggs will be found arranged
very regularly in the cavities which have been made to receive
them. If the eggs have recently hatched, their transparent and
shrivelled shells will be all that can be found. After a few days

Fig. 8.— From Bui. 14, N. S., U. S. Dept. Agr., 1898.

fi';

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of'

15

these shells will have disappeared^ being eaten by the numerous
ants which constantly swarm on all parts of the tree. It may be
that occasionally the eggs are found by the little red ants and eaten
before they are hatched, but as the fibers of wood left by the boring
of the female Cicada pretty effectually close the cavities, this is not
probable.

During the months from January to April, 1903, all sizes of
larvae and the pup^ were found when cacao trees were dug out.
During this same period the adults were fairly abundant, as were
the cast skins of the pupae on the trees. It is therefore probable
that the period of greater abundance of the adults is during the
latter part of the year, probably in October and ISTovember.

The question of the killing of larvae after they have once entered
the ground is a most difficult and serious one. There are few
substances which have sufficient penetrating power to enter the
soil and be effectual against the larvae without endangering the
young roots of the trees. Probably one of the most useful of these is
carbon bisulpliide, an extremely volatile transparent liquid re-
sembling highly refined petroleum, but having, when not pure, an
extremely disagreeable odor. It is highly inflammable and heavier
than the air, and therefore sinks readily into holes or crevices in
the ground. Its extreme inflammability renders great precaution
necessary when handling it. It must not be kept in houses where
lights are used, nor must it be left in large quantities in bright
sunlight, and the vessel used to contain it must be capable of being
sealed. The fumes of this chemical, while not actively poisonous
when breathed by human beings in limited quantities, are extremely
disagreeable and are productive of headache. If inhaled for a mod-
erate length of time they cause suffocation. The substance should
be handled only by those who are thoroughly acquainted l)eforehand
with its properties, and then only by those who can be trusted to
carry out instructions concerning its uses. It should be kept where
it can not be reached by children, and should be labeled
"Poison.'^ Glass-stoppered bottles or tin cans having the best qual-
ity of cork stoppers are the best receptacles for carbon bisulphide.

It is possible that gasoline or naptha would in a measure serve
the same purpose as carbon bisulphide, but no experiments have
yet been made to verify this supposition. Either of the liquids
would have the advantage of cheapness over carbon bisulphide.

At present the price of this chemical in the Philippines is such

16

that the general use of it as an insecticide is almost out of the
question. In the United States, when bought in large quantities,
it may be had for about 15 cents per pound. By the single pound
it costs about 25 cents, gold. In the drug stores of Manila it may
be bought at 75 cents, gold, per pound; or 55 cents, gold, in quanti-
ties of from 50 to 100 pounds. It is hoped that with this, as with
other important insecticides, some plan may be devised to enable
tJie farmer here to procure them at a lower cost.

The most effective method for the application of bisulphide to
trees for the killing of insects attacking the roots, and the one
which is least dangerous to the tree, is as follows : The trees may
1)6 treated successively by one or several men. An instrument
should be used by which a hole 50 or 60 cm. deep and 2 cm. in
diameter may be bored into the earth, about half a meter from the
crown of the tree. There should be three of these holes equidistant
around each tree, and into each should be poured not more than
25 c. c. of the carbon bisulphide. The hole, after introducing the
liquid, should be immediately stopped up with wet earth or thick
wet cloths, and left in this condition for several hours. The cloths
can then be taken away, or the ground raked or leveled if earth only
has been used. These measures can be tried at any time, but pre-
ferably Just after a period when a large number of twigs of the
trees have been found lacerated by the female Cicadw, as in all
probability the eggs will have been but recently hatched and the
larvae therefore but a short distance below the ground.

When A nay or ants are found working below the crown of the
tree, similar measures for their extermination may be employed. A
dampened canvas or other air-tight cloth may be placed around the
base of the tree, in the form of a conical tent with a broad base.
After earth has been packed around the base, a small quantity,
from 15 to 20 c. c, of carbon bisulphide may be poured upon the
ground within the tent and the whole thus left for half an hour.
If rightly applied this remedy will kill all insects within the
inclosed area without doing damage to the tree itself. The
method here described applies only to trees which have attained
their full growth, and Just after the bearing season. With smaller
ones a proportionately smaller amount of the bisulphide should be
used.

Fig. 11.

Fig. 12.

17

WHITE GRUBS.

Not only will the method described for the killing of the larvge
and pnpse of Cicada prove effectual for these insects^ but it will
also be equally so against the white grubs so commonly found
among the roots of the cacao tree.

These white grubs are the larvae, of one of tlie Lamellicorn
beetles and belong to the genus Anomala, the adults of which
have been found in cacao plantations in some abundance. In
general, the habits of all beetles of this genus are the same. The
adult of a very common species is shown by fig. 10, and the larvae
of the form found in the cacao root by fig. 11. It is not known
how or where the eggs are laid, but they are probably deposited
in the debris which naturally collects around trees which are ill
cared for. The larvae, upon hatching, have but a very short distance
to go, in the case of the cacao, before they find the young tender
rootlets upon which they feed with avidity.

These larva? can be very easily recognized. The form of tlie
body is characteristic. When found they are invariably curled up,
assuming this jDosition as a means of defense. Tlie f id 1 -grown
larva measures 3 cm. in length and about 5 mm. in diameter.
The long, rather slender, yellowish, hairy legs are bent forward at
the first joint. In crawling the insect uses them very awkwardly.
The head is ochre-yellow, shiny, and covered rather sparsely with
stout bristle-like hairs. Examination with a strong liand-k^ns re-
veals the fact that there are no eyes, at least none externally. The
dark-brown jaws or mandibles are well fitted, by their form and
position, for cutting off bits of the roots upon which the animal
feeds.

The body has a somewhat corrugated surface, and upon the
back of each segment there is a transverse area covered with fine,
brown, very short bristles, which aid the insect in burrowing into
the ground. The rear four segments of the abdomen are somewhat
broader than the others and are of a darker color, owing to the
mass of excrement contained in the alimentary canal.

That these insects do much damage to cacao is evident from

their abundance and the fact that they are related to species which

are very injurious wherever found in other parts of the world.

Living as they do for the greater part of their lives below the

10852 2

18

surface of tlie ground^ where cultivation of the plant will not dis-
turb them, they form one of the hardest classes of insects to com-
bat. The effects of their work are not apparent until the weak and
dying condition of the tree, and its inability to bear fruit, tell the
grower that it is being killed by some unseen insect enemy. The
full-grown insect, a beetle, is shown in fig. 10. It measures from 9
to 12 mm. in length, is of a shiny greenish-brown color, and the
wing-covers are very much rounded. Fiiie striations, running
longitudinally upon the wing covers, heighten its sheen. The
beetles are usually found upon the leaves or in crevices in the bark,
where they appear to be always in hiding. These beetles are very
peculiar in their habits, invariably simulating death when they are
disturbed; they then drop to the ground, where they lie perfectly
motionless among the rubbish around the tree until the disturbance
has passed. If care be used, a very slight jarring of the tree will
cause them to drop from it to the ground, where, if there be no
debris, they may be seen and killed. A word of caution, however^
should be given as to jarring the trees. Perhaps no tree cultivated
is so susceptible to ill treatment as the cacao. The fruit, because
it is so large and heavy, may be shaken off by even a strong breeze,
and it is therefore evident that jarring, when the tree is in fruit,
will prove most disastrous to it. Only such trees as are just out of
fruit or in the blossom season should be treated in this manner, and
the janing should be done with the palm of the hand ; a gentle blow
being delivered, and only repeated two or three times for each tree.
Anything more severe than this will result in disaster.

For killing the larvge of the beetle above described the same
methods as those employed for killing Cicada larvae may be used.

When this insect is ready to change to the pupal stage it builds
a cell, composed of compacted earth. This cell is somewhat larger
than the larva, and, as the latter shrinks considerably just previous
to the pupal stage, there is sufficient room for it to effect the final
change to the adult, allowing for the proper expansion of the
wings and wing-covers. While in this pupal cell the insect appears
as in ^g. 12.

While birds, particularly crows, feed most readily upon all
forms of white grubs when they are exposed in fields by plowing,
it is very doubtful if they perform any appreciable service in the
destruction of the Anomala unless it be that they pick the insects
from the trees when they have reached the adult stage. Therefore,

19

all efforts against these pests will consist of the destruction of the
larvae at the time of application of remedies for the Cicada and the
jarring of the beetles from the trees as described above.

INSECTS ATTACKING THE TRUNK.

ELAT-HEADED BOREK.

Of all the cultivated plants observed in the Pliilippine Islands^
perhaps none has been found which suffers more from insect attacks
on the trunk than does the cacao. The insect which is of first im-
portance is the flat-headed borer of the cacao. It belongs to the
family of long-horned borers^ the Ceramhycidw, an adult of which is
shown in fig. 13. The. damage by this insect is much greater than
that produced by any other insect attacking the cacao^ inasmuch as it
not only works for a long period unseen in the trunks but finally
effects the death of the tree^ and the damage is hardly apparent to
a casual observer until its work is completed.

Ninety per cent of all trees examined in the Island of Negros
were found more or less completely damaged by this insect. The
mode of attack and the results are so characteristic that when once
described they will be noticed by the most careless observer^ and
will be always remembered as the work of this particular insect.

Going through a cacao plantation at certain periods in the year,
especially in April and May, one will frequently notice at the bases
or upon the trunks of the trees a kind of coarse fibrous sawdust.
This may be of a light wood color, or of a very dark mahogany red
if there has been a recent rain. One who is not acquainted with
the facts might well suppose that this has been produced by the
gnawing of some small animal like a rat, though upon closer exam-
ination it will be seen that the fibers are too regular to have been
thus produced. If the bark be examined carefully one will soon
find a small hole of irregular form, about 1 cm. in diameter, from
which there appears to be exuding more sawdust, usually of a
dark color and wet if recently pushed out of the burrow by the
insect. If a hooked instrument or a knife be used to carefidly
remove the flakes of dead bark found around the hole, there will
be found more of the same material underneath. If the search be
continued, following the line of a now w^ell marked burrow, the
chances are that at its end, whether just below the bark in the
sapwood or within a deeper burrow toward the heart of the tree will
be found a large, yellowish grub with darker head and still darker

20

brown jaws. The body is larger toward the head and somewhat
flattened^ giving the insect the name fiat-headed borer. The body
segments are well defined^ as shown in fig. 14. The darker color of
the hinder part of the body is due to the fact that the digested
wood becomes colored by the juices in the alimentary canal of
the larva. It would be well to state here that the fibrous masses
of wood found in connection with this insect have not been used as
food^ but were simply cut away in the process of making the pupal
cell and in filling up its entrance^ in order that the grub might not
be disturbed in its transformations to the pupal and adult stages.

This larva may well be described as a footless grub; one which
is perfectly helpless when removed from its burrow, for when on(3e
taken out it is not only at the mercy of predacious insects like
ants, but is of itself so helpless that it would soon die from lack
of moisture before it could reach a place of safety.

The full-grown larva measures 40 mm. in length and about 4
mm. in diameter at the middle of the body. Its powerful jaws or
mandibles enable it to feed readily upon the hardest parts of the
w^ood in which it lives, and specimens have been found which have
excavated tunnels 50 cm. long, in addition to the irregular blotch-
like cavities which are formed just beneatli the bark at the begin-
ning point of the attack.

The habits of this insect are very similar to those of related species
in other countries, as the maple borer, Plagionotus speciosus; the
sawyer, Monohammus confusor; the round-headed apple borer,
8aperda Candida; the oak pruner, Ela/phidion viUosum. The female
lays her egg in a small puncture in the living bark of the tree, and
as soon as the young grub hatches it begins its work of tunneling
the bark, the tender growing wood, and eventually the harder
portions of the tree. Were it true that a single borer did its work
in the trunk, the damage, though considerable, would not be
so serious a menace to the life of the tree. But when several
borers appear simultaneously in diff'erent parts of the trunk they
soon succeed in girdling it, after which the tree is sure to die.
Figs. 15, 16, and 17 show several large-sized branches killed in
this manner. The grubs having injured one side of the tree,
the latter puts forth its strength in efforts to heal the wound,
causing an abnormal growth to bulge over the bare space left by
the insect attack. The wood and bark increase in thickness on the
opposite side. Other grubs attack this part, which is particularly

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21

rich in food material^ and thus by tliese successive attacks the
living parts are all destroyed and the tree girdled.

Trees have been frequently observed in which^ on a branch from
4 to 7 cm. diameter, there would be a strip of only le5 mm.
of living wood, and yet this branch would be giving forth leaves
above the wound. Of course the latter were small, being ill nour-
ished^ and no fruit could be expected upon such a branch. This
illustrates the remarkable vitality of the cacao, and probably
also explains its extreme susceptibility to injuries of any kind.

An interesting feature of the work of the tiat-headed borers is
the manner in which the excrement is packed behind it in the
burrow, sometimes so solidly as to simulate the wood itself. It
can, however, always be distinguished by its gramilar appearance
instead of the fibrous structure of the wood. These filled burrows
are frequently encountered in timber when it is sawed for building
and other purposes. Wood having this appearance is called
^Svormy.^^ Characteristic burrows of one of these larvae are shown
in figs. 18 and 18 a, and in fig. 18 /; the frass as left behind.

When the grub is about to pupate it burrows toward the heart of
the tree and upward, thus forming an oblique canal, which, when
a short way in, is changed to a vertical direction and is thus parallel
with the wood fiber. Into this burrow the insect retires and changes
its position so that the head is toward the opening. Within a very
short time after the larva has entered this retreat and has packed
in the fibers to close up its doorway, it sheds its skin as a grub and
assumes a form which, upon closer examination, shows that it
possesses characteristics of a 1)ectle. The legs, antennae, wings,
and wing-covers may all be readily distinguislied if a careful exam-
ination be made. Unfortunately, there have not yet been sufficient
observations upon this insect to enable me to state the length of
time during which it remains in the larval and pupal stages. On
March 11, 1903, a full-grown beetle was taken f]-om a tree
near one in whicli larval and pupal forms had been found at an
earlier date of the same year. This would seem to indicate that the
period for the pupa is from four to six weeks, possibly not so long.

The adult, after its outer covering has become tlioroughly dry
and hard, subsequent to its change from the pupa, begins the work
of gnawing away the material which, as a larva, it had packed in
the mouth of its burrow, and it comes fortli a very beautiful crea-
ture, entirely unlike the uncomely grub which had been doing

22

the damage. Its length is 25.5 mm.^ its greatest breadth 6.5 mm.
The antennae in the specimen before me measure 44 mm. When
the insect is at rest, the antennae are carried back over the bod}^,
projecting beyond the tip of the abdomen. The antenna has 11
joints, the second from the head being much thicker than the others
and having transverse corrugations or lines upon its upper surface.
Each succeeding joint, except the three last, is knobbed at its
extremity and bears a spine on the hinder edge. The eyes, which
are black and composed of what appear to be a number of fine jet
beads, are crescent-shaped and are placed around the hinder edges
of the sockets of the antennae. The thorax is very markedly cor-
rugated transversely and is covered with fine golden-brown hairs
which give it and the wing-covers, which are similarly marked, the
appearance of a beautiful brocade velvet. The legs are rather long
and slender. They are covered with fine hairs, as is true, also, of
the under surface of the body. The feet are provided with a pair
of hooked claws which aid the insect in clinging to the bark. In
the act of egg laying the female grasps the bark firmly with all
her feet and is thereby enabled to insert the ovipositor into the
bark.

The beetles of this family make a peculiar noise when disturbed
or captured. It is similar to the sound produced by rubbing the
finger nail over a very fine file, and is made by the friction of the
tip of the wing-covers on the surface of the abdomen.

The question of combating this insect is a very serious one, as
the methods employed must at once be easy of application and
likewise effectual at the time when the insect is likely to begin its
greatest damage. The beetle almost invariably rests upon the
bark, which is so nearly its own color as to make it very difficult
to detect. It is therefore evident that any attempts to thus dis-
cover it and rid the trees of this pest by hand picking would prove
practically useless. In order, therefore, that the insect be repelled
from the bark, something must be used which will prove at once
distasteful to it and harmless to the tree. Probably the very best
method with young trees, when recently set and until they reach
an age when the bark will not be susceptible to the effects of any
strong wash which may be applied, is the complete enveloping
of the trunk of the tree by means of protectors made of a
coarse grade of abaca or sinamwy, such as is used in the Visayas
for mosquito netting, and which has a mesh sufficiently fine to

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23

prevent the entering of the adult for egg laying. This material
is so cheap that it could be used constantly^ even until the trees
have attained a considerable size. The bags are made of a cylin-
drical form^ open at both ends, and having a drawstring in one
end. They may be slipped over small plants and the lower ends
held close to the ground^ either by embedding in earth or by the
placing of stones upon the lower edge. In the case of larger
trees, where it is impracticable to slip this bag over all the branches,
it is well to simply use a straight piece of cloth, putting it around
the tree and after doubling the edges together in the form of a hem,
they may be either sewed with coarse stitches or pinned by means
of sticks of bamboo made in the form of toothpicks. See fig. 19
for an illustration of a bag which was used for the protection of
the upper part of the trunk in order that, during investigations,
the adults which em^erged from the tree might not escape. In fig.
20 are shown trees protected by these bags. Opened at the bot-
tom and held close to the ground by stones or earth, they serve
admirably for keeping off the beetles. Wire screening would serve
equally as well were it not for the fact that the extreme dampness
would cause it to rust and thus quickly become useless. In the
United States a heavy grade of tarred or roofing paper serves the
same purpose, but its cost would be against its general use in the
Philippines.

Where it is not practicable to use the method described above,
some repellant to the insects, should be applied to those parts of
the trunk which are most likely to be affected. Inasmuch as
these repellants are simply supposed to keep the adult insect from
laying her eggs, it is very obvious that they should be applied
before any insect has had a chance to deposit its eggs in the tree
trunk. If the grub has once entered the bark, no application of
remedies externally will have the least effect upon it and other
means must be taken. These will be spoken of later. Any strong-
smelling substance, such as fish oil, tar, or pitch, which will adhere
to the tree, or pure crude petroleum, would prove effectual, but
perhaps the best and most easily applied material for warding off
the attacks of this borer is what is known as the soap and carbolic-
acid wash. This is prepared by dissolving four liters of soft soap
in four liters of hot water and adding one-half liter of crude
carbolic acid. This mixture should stand for at least twenty-four
hours, or until it has become perfectly dissolved. Into this should

24

be poured from 32 to 40 liters of rainwater and tiie whole carefully
stirred until thoroughly uniform. It may then be nsed with a
broad paint brush or swab on the end of a stick, covering all the
parts of the trunk and branches which might be supposed to offer
a place for the borer to lay its eggs. 'No fear need be had that
this mixture will injure the trees if properly prepared in the pro-
portions given. The period from the first of April to the first of
June would be the best in which to apply this preventive, as it
is during this time that the beetles come forth and are ready to
lay their eggs.

An excellent preventive which has been used most successfully
against the peach borer in the United States and which would
probably prove of value equal to that of the carbolic wash, is a
preparation composed of lime, coal tar, and whale-oil soap. This
mixture may be put on in a comparatively thin coating, as ordinary
rains do not easily wash it from the trees. It must be thoroughly
applied to all parts of the tree likely to be attacked by the borers.

Tobacco dust has been advocated by some fruit growers in Amer-
ica as a preventive of the borers. The author leaves this matter
until more thorough experimentation in the Philippines shall
determine the advisability of recommending it for general use.
If it be found an effectual remedy, there would be a decided advan-
tage in employing it in lieu of insecticides w^hich would have to
be brought from abroad.

An effective measure to be used against the grubs which have
already entered the tree is to carefully search for evidence of their
existence beneath the bark, and when they are located to thrust
in a stout piece of bent wire, which which they can be crushed.
It is not necessary to extract the crushed insect, as when so injured
it can not transform further and there will be no danger of its
coming forth as a beetle.

The fact must be constantly borne in mind by those who would
grow cacao successfully in these Islands that vigilance, not only over
those charged with the work of caring for the trees, but also personal
inspection of the orchards themselves by the owners, will be neces-
sary to detect' not only the presence of these insects, but also a large
number of other forms whose insidious working in places in
which it is not easy to get at them, renders them all the" more
pernicious. As in a clean house or in a clean city, diseases are less
liable to enter and play havoc, so, in a clean cacao orchard, insects

25

find less favorable fields for their ravages. This means that thor-
ough and scientific pruning^ careful cultivation as set forth in
Lyon^s Bulletin on Cacao Culture/ and a constant care must be
taken against insect and other pests. Clean ground around the
cacao trees proves less inviting to all kinds of insects which would
be liable to lurk in the rubbish and dead leaves which often litter
the plantations so far observed.

WHITE ANT OR TERMITE.

Another insect which has proven seriously destructive to the
trunks of cacao trees is the ^Vhite anf ^ or termite. This insect^
described as being destructive to the roots^ does not by any means
confine itself to these parts of the tree. Fig. 2 shows the work
done in the living trunk of a cacao which had first been seriously
injured by the borer. When once the white ant becomes abundant in
a tree^ the life of the tree is practically doomed^ unless the measures
suggested on page 16 be followed before the insects have extended
high' into the tree. These termites have an underground cell in
which the queen-mother of the colony is confined; owing to her
great size she can not leave this cell, and performs no other function
save the laying of eggs, with which her enormous body is distended.
Fig. 21 shows a female, natural size, of a species closely related to
the one which damages cacao trees. Fig. 22 shows the same kind of
insect before her body has become distended with eggs. Unless this
queen-mother be destroyed in some way the colony will go on mul-
tiplying indefinitely, it matters not how many of the ants found in
the tree be killed. There are always thousands of workers in the
ground chambers of the nest to attend to the rearing of the enor-
mous brood. Fig. 23 shows the cells in which the young are reared.

In order to find out approximately the number of eggs laid by a
female, a complete queen cell in which the queen-mother was con-
fined, was dug out. Fig. 24 shows the appearance of a cross section
of this cell. The female was carefully watched for several hours
and was seen to be continuously laying eggs. These eggs were car-
ried away in tiny adherent masses by the workers. A watch was
made for one minute, and instead of allowing the workers to re-
move the eggs during this period, the mass was carefully picked
up with a fine forceps as fast as it had assumed the size of those

^See Bui. 2, Philippine Bureau of Agriculture, 1902.

26

previously carried away by the workers. A count revealed the fact
that during one minute 165 eggs had been laid by the queen-mother.
JSTo exact estimate of the weight of this mass was made, but it is
safe to say that it represented not more than 1-1000 of that of the
female when fully distended. Some idea can be gained from this
of the wonderfully prolific character of the termite, and the futility
of attempting to destroy a colony without first killing the queen-
mother.

The same species of large black ants, which were mentioned as
attacking the tree below the crown and among the roots, will like-
wise be found in the trunk, especially after the attacks of the borer
and the termite or anay. They do not attack the trunk very high
up, seeming to prefer living half beneath the ground. The same
treatment recommended for this insect when found among the
roots will apply to it when found in the trunk of the tree.

PSOCID^.

A little insect which is often rather abundant upon the trunks of
cacao trees is a species of Psocidw. This little fellow is perfectly
harmless, feeding only upon the lichen growths which are to be
met with. It should not be confused with the winged forms of plant
lice which are very injurious. This species of Psocus is red and
black; the body being red and the wings mottled and of a smoky
color. They are often found bunched together in considerable num-
bers on the lower trunk near the ground, and when disturbed scurry
to one side like a flock of sheep, leaving a bare spot where the dis-
turbing influence touched them. Among these aggregations the
larvae, which are wingless, the pupse, which have tiny wingpads, and
the adults, which have fully developed wings, may be found. Fig. ,
25 shows a portion of a cacao tree trunk covered with these insects.
As they feed upon substances entirely foreign to the life of the tree
and simply use the latter as a place of abode, they may be classified
as not being harmful.

Very frequently caterpillars will be found resting upon the
trunks of cacao trees during the day, while at night they will be
found feeding upon the leaves. These are often so nearly of the
same color as the bark that they escape all except an eye trained to
look for such things. On particular species of caterpillar belonging
to the family Lymantriidce is so nearly like the caterpillar of Por-
thetria {Ocneria) dispar, the Gypsy Moth, as to indicate a very

Fig. 25.

Fig. 26,

27

close relationship between the two, bnt as I have not yet succeeded in
rearing the adult, the insect has not been determined. The habit
of placing the cocoon or nearly naked brown chrysalis in forks of
the twigs and in holes in the bark is almost identical with that of
Forth etria.

The caterpillar will be described when the insects which injure
the leaves are discussed.

INSECTS ATTACKING BRANCHES AND TWIGS.

Three very serious insect pests which attack the small branches
and twigs, girdling the bark of the latter at its junction with the
stem, have been found in the larval stage, but all attempts at rearing
or finding the adults have so far proven failures. (Fig. 26 will
show how thoroughly the larva of one has done its work of girdling
a twig which was 26 mm. in diameter. Fig 26 a shows a twig 13
mm. thick which is also completely girdled by the insect.)

A peculiar and interesting habit of the larva, which first attacks,
the twigs to girdle them, is that of using its excrement, together
with silk, for covering up the burrow or retreat in which it lives.
This is very neatly done by fastening the particles together with a
kind of silk and these pellets or particles of frass are so nearly the
color of the bark from which the animal has obtained its food that
the difference between this and the sound bark is often not noticed
except upon closest observation. This larva is of a dull greyish
color with a brownish head. Its body is sparsely covered with stiff
bristles and its general habits are similar to those of the Tortncidce,

The second larva is undoubtedly a Ceramhycid, but as has been
said it has only been found in this stage and can therefore not be
identified at present.

The destructive work of Cicada has already been mentioned in
reference to insects which affect the roots of the cacao and its
habits of laying its eggs in the twigs make it likewise one of the
insects injurious to the twigs and branches. The mode of treating
twigs thus affected would be to cut off and burn all twigs in which
the Cicada eggs have been laid. One will frequently come upon
a twig or even a good-sized branch which bears a peculiar scar
like those shown in fig. 27. If a careful examination be made this
will be seen to contain shrivelled egg shells about 4 mm. in length.
Twigs will be found like that represented in fig. 28, in which the

28

eggs show very plainly. The adult which lays these eggs has not
yet been founds but from the general appearance of them it is
very likely that the insect is an Orthopteron; that is^ belong-
ing to the order of grasshoppers^ crickets^ etc.^ and may be one
of the katydids^ some very large species of which have already
been taken in cacao groves.

Microcentrum retinervis, the angular-winged katydid of the
Southern United States, lays its eggs, which are of about the same
size as those shown in fig. 29, upon the edges of leaves and upon
the stems of the trees which it inhabits, and therefore it may
reasonably be supposed that the destructive insect in the case of
cacao is a related species.

With many insects of this and other species affecting the cacao,
long periods of observation and the collection of more material will
be necessary in order to become thoroughly acquainted with their
entire life history. In many instances thus far only one stage,
or the work alone, of the insect doing the damage, has been obtained.

INSECTS AFFECTING THE LEAVES, ETC.

PLANT LICE.

One of the most serious pests of the leaves, tender buds, and
flowers is a species of black plant louse. This insect attacks the
young buds even before the leaves or the flowers have opened. The
tiny eggs are laid in the folds of the buds and the bud scales,
beneath the stipules of the leaves, and in the crevices of the un-
opened sepals of the flowers. They are so minute that they can
only be seen with the aid of a magnifying glass. As soon as the
young hatch, they pierce the skin of the twig upon which they
rest and begin sucking the plant juices. Some broods of plant lice
give birth to living young which in turn lay eggs. This question
of the alteration of the mode of reproduction is very interesting
to the student of biology, but has little value economically, at
least in this latitude. The young plant lice resemble the adults
in form. They are of course much smaller and have no wings,
but as certain forms of the adults are also wingless, this feature
alone will not aid in distinguishing the stages.

Plant lice are provided with a pair of spine-like projections
which are little tubes on the back of the abdomen and which
secrete a waxy substance ^hich is much sought by ants. This

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29

substance is commonly known as "honey dew/^ Its nature is not
clearly known. -Generally, in examining a colony of plant lice the
surface upon which they rest will be found to be sticky and glis-
tening, as though covered with sirup. This is the "honey dew^'
secreted by the plant lice. It is for the purpose of collecting this
that ants invariably attend a colony of the former, caring for them
assiduously in return for the "honey^^ which they secure. They
frequently carry the plant lice from place to place when the leaves
or twigs, upon which the latter have been feeding, become dry and
hard.

Even though only a single plant louse be found upon a leaf or
flower, it is almost invariably attended by an ant and sometimes
by two or more. Thus cared for, it is little wonder that the plant
lice multiply and flourish to a remarkable extent. Fig. 30 rep-
resents the difl^erent stages of the plant louse. It will be noticed
that at b the pupa is distinguished by the tiny wing pads which
contain the wings. These insects feed in all stages, from the
larva to the adult, and therefore their damage is considerably
greater in proportion than that done by insects which feed only
in the larval stages, like Lepidoptera, Dipt era, and Coleoptera.
Their small size appears to be fully compensated for by their
numbers, and so the cacao grower has to be ever vigilant in order
that he may successfully combat them.

The immediate effect of the attacks of the plant lice is to cause
a drooping or wilting of the leaves, flowers, or flower stems which
they attack. This is followed by a distortion of the part, the
leaves curling toward the under side, where the plant lice are
usually found. This shrivelling is very marked upon some trees,
and when the leaves have attained their full growth they will be
found to be undersized and broken because of their efforts to out-
grow the attack. Flowers, when attacked by the plant lice, shrivel
and die without producing fruit. Occasionally the plant lice are
found upon the very young fruits, the skin of which is almost
as tender as the young leaves. Invariably fruits thus attacked
either die from exhaustion, or if they survive are very much dis-
torted, presenting, instead of the regular, even-lobed appearance
of the perfect pod, a scarred smooth side which has no semblance
of the characteristic ridges. In this way the pods are formed in
which the tip, instead of being straight, is twisted by arrested
growth on one side and by tlie normal development on the other.

30

Fig. 31 shows a fruit thus distorted, and a perfect fruit is shown
in the frontispiece.

When the fruit pods have attained the size of a hen's egg- they
are not subject to the attacks of the plant lice and thus it will
be evident that any remedy should be applied before this period.

As a means of treating plant lice upon the flowers and leaves
of cacao, there is no better material than kerosene emulsion.
There are several ways of making and applying kerosene emulsion,
but the best preparation for this purpose will be found to be the
kerosene and soap emulsion. This, if properly prepared and
applied according to directions, will be found to be harmless to
the most delicate parts of the plant. For its preparation see the
chapter on Insecticides.

In applying the kerosene emulsion some kind of spray pump
should be used to facilitate the uniform distribution of the liquid
and to enable the sprayer to reach the higher branches of the tree
with the emulsion. In another chapter brief descriptions will be
given of some of the essentials of standard spraying machines which
have been u^sed successfully in the United States in combating in-
sects similar to those found on the cacao.

BLACK THRIPS.

Another enemy of the young cacoa leaves which is likely to
prove of considerable importance is the black thrips. This minute
insect may escape even a close observer if he does not know the
signs which indicate its presence. As in the case of the plant lice,
the injury caused by the thrips makes the leaves curl up, as shown
in ^g. 32, but not as markedly as with the former. If we care-
fully examine a few leaves which show evidence of curlings, we
will find upon the under side a number of very slender black and
red objects moving very slowly from place to place. The black
ones are the adults, the red ones the young thrips. The rear part
of the abdomen is decidedly pointed, and the thorax bears a spine
on each side. These insects are provided with sucking mouth-
parts and cause an injury to the leaf similar to that caused by the
plant lice. They maj be combated by the same means employed
to destroy the latter, and large numbers of them will be killed
when the trees are sprayed for the Aphids. Two adult thrips are
represented much enlarged at fig. 33.

A

^^-:a^.«^l'"

%.

n

1

1

1

1

Fig. 34.

YELLOW SCALE.

Another insect which/ while not occurring in great abundance
■at the time when observations were made, is likely to prove a pest
to the cacao, is the large 3^ellow scale represented magnified in iig.
34. Its eggs are shown at A. The adult female measures 17.5
mm. long, 13 mm. wide, and 9 mm. high. It is of a light salmon-
yellow color and is covered with a fine powdery substance. Be-
neath, the scale secretes a white material which is fibrous in struc-
ture. The upper surface is corrugated; the hinder part of the
body is much higher than the fore part, and wlien at rest upon
the twig or leaf the black legs and antennge are completely hidden
by the shell-shaped body. The forward part of the body is
slightly notched. When the animal is disturbed and moves from
place to place, the tiny black antenna and tips of the black feet
may be seen protruding from beneath the shield-like body. In
February and early March these insects will always be found with
the space beneath the dome of the body completely filled with tiny
•orange-yellow eggs which are 1 mm. long and O.G mm. wide. It
is not yet known when the young hatch, nor has anything definite
heen ascertained concerning the full life history of this insect.
Further studies will elucidate points concerning this and other
scale-like insects of the cacao.

The same method employed in ridding the trees of the Aphids
will apply to the combating of the large yellow^ scale. Its soft
body will make it peculiarly susceptible to the effects of kerosene
emulsion.

Very frequently there will be met in the cracks and crevices
under the dead bark and in holes wdiere limbs have been ])roken
off from the cacao a beautiful, irridescent, blackish green or
blackish purple beetle with very convex wing covers and ant^nna^
which have the appearance of a string of beads. This beetle be-
longs to the family Sphindidce, a class of beetles whose larvae feed
upon dry fungi and decaying vegetable matter and which arc not
injurious to the tree. When disturbed these beetles readily simu-
late death and will drop to the ground until the disturbance has
passed. They have been found in fair abundance in all cacao
plantations.

The beetle measures 14 mm. in length and 5.5 mm. in width,
the wing covers being 9 mm. long. The wing covers are marked

32

by a series of 9 longitudinal lines which are punctuated by fine
dots. The under surface of the body is of the same color as the
upper surface. See fig. 35.

Occasionally there may be found upon the under surface of the
beetle, tiny light-brown, roundish mites which are parasites. This
is a thing which is very common to Wi2i\\j Cole opt era, especialh^
those living in dark or obscure places.

Associated with the beetle may be found several species of cock-
roaches, some of a very pale yellow and about 15 mm. long, others
mottled buff color, 20 to 25 mm. long, and still others which are
about 35 mm. long and of a reddish-brown color. None of these
do damage to the trees, as they live upon the decaying matter
found in the (^reviccs and wounds.

Other liarmless forms pertaining to TJiysanura, Coleoptera, Gor-
rodentia, and Ortkoptera have been met with upon the trees, but a
description of these minor insects and of their life histories and
hahits will be left for a later bulletin. In any attempt at treating
the trees for injurious insects many of these will inevitably be
killed.

CATERPILLARS.

The two principal destructive insects found upon the leaves
are a species of caterpillar of the family Lymaniriidw and others
of the family Eudeidw. The caterpillar of the former, mentioned
on page 27 can be easily recognized by its size and its hairy appear-
ance. A¥hen full-grown and ready to transform it measures 33
mm. in length and 10 mm. wide, without the hairs, which add 12
mm. to these dimensions all around, making the entire caterpillar
occupy a space of 53 mm. by 30 mm. on the surface of the leaf.
The adult and the egg-laying habits of this insect are not known,
but it is probable that the female lays her eggs in patches upon
the twigs, covering them with soft down from the outside of her
own body, like a closely related spcies found upon the ylang-ylang
and the talisay trees. These caterpillars, as has been stated, have
the habit of feeding at night and resting npon the branches and
the trunk of the tree during the day. When disturbed, they raise
the head and twitch the fore part of the body from side to side.
Jf the disturbance be continued, they drop either to the ground
or to a lower limb. The color is a dnll gray with a few reddish
markings. The head is very large, grayish, and marked by darker

33

patches of small dots. The hairs which project forward from the
neck give the insect the appearance of wearing a ruff. When at
rest upon the bark^ the false legs of the abdomen^ ten in number,
are spread out beyond the sides of the body, firmly grasping the
surface upon which the insect is resting. When the caterpillar is
about to change its skin or moult, a process which it performs five
times before changing to the chrysalis, the six true feet are drawn
up together, the head is drawn down toward the legs and the fore
end of the body is elevated. This insect, before pupating, finds
a convenient place at the fork of a small twig or in a crevice in
the bark, and there it spins a very poor apology for a cocoon.
The cocoon looks more like a wide-meshed basket than a true
cocoon and doubtless serves simply to keep the large brown chrys-
alis from falling to the ground. Unfortunately, several of these
chrysalids which were put into a box for rearing, transformed to
the adult stage in transit to Manila from the place of capture and
were so disfigured as to be unrecognizable when the box was opened.

In addition to the long hairs which cover its body, this caterpillar
is provided with short, stout bristles 3 mm. long. They grow
from tubercles on the upper parts of the abdominal or thoracic
segments, and are spread out in tuft form. These bristles are
very sharp and when the observer is pricked by them the sensation
is a very painful one. It is claimed by Filipinos that these
animals are very poisonous and- undoubtedly this belief comes from
painful experiences with their poisonous spines. On many people
the prick of these spines causes great swelling and inflammation,
which may continue for some days. This is due to the fact that
the spines work their way through the epidermis into the lower
skin and there remain for some time. If one handles these insects
by mistake, the best way is to carefully pick out all the spines
with a pair of pincers, using a magnifying glass if necessary to
aid in the work.

The pupa is likewise covered upon certain areas with very minute
spines not more than 1 mm. in length, which have the same prop-
erties as those upon the caterpillar.

The pupa of this insect is much shorter and stouter than the
larva, measuring only 23 mm. in length. Fig. 36 shows the full-
grown larva and fig. 37 the pupa.
10852 3

34

SLUG CATERPILLARS.

The other caterpillar which is nearly as severe in its attacks
as the hairy form is what is commonly termed a sing caterpillar.
The slug caterpillar is so called from the fact that instead of pos-
sessing well-developed legs and prologs (false abdominal legs) it
has the nnder side of the body so modified that for its entire length
it is closely applied to the surface npon which the insect crawls.
The form of the caterpillar is most striking, and once recognized,
these larvse can not be mistaken for any other. The body, which
in the full-grown larva measures 9 mm. long, is shaped much like
a slug or snail, except that it is perfectly square across the back,
the sides being also perpendicular to the back. The very pro-
nounced margin which separates the side from the back is armed
with a series of erect spines of a mottled brown color with black
tips. There is also a row of these spines on each side near the
ventral or lower surface of the caterpillar's body. A peculiar little
tubercle armed with two of these spines projects from the rear of
the body and slightly upward. When feeding, the caterpillar pro-
trudes its head from beneath its spiny armor and when disturbed
it can immediately withdraw^ it, pulling the fore part of the body
down over it for protection. When touched upon one side the
insect immediately doubles over toward that side, just as a person
would do if tickled. If touched upon the opposite side, it performs
a similar movement in that direction. The general color of the
insect is dull brown, but the under surface is pale, almost white,
and very smooth. The caterpillar secretes a kind of a slime which is
evidently useful to it in its movements upon the leaf, serving in
place of legs to hold it. When it is about to transform to the pupa,
it spins a very tough, thick cocoon which is nearly spherical in
form and is attached to the leaf or the twig. This little cocoon is
brown and very smooth and glossy. It bears no resemblance to
anything pertaining to an insect except to the tiny galls formed
by certain hymenopterous insects upon trees like the oak, etc. It
looks more like a little, dry, brown fruit of some kind.

The damage the caterpillar does to the leaves is shown by fig. 38.
As the eggs are always laid upon the under side of the leaf, the
insect begins by eating off the lower skin or epidermis, leaving only
the veins which give the peculiar skeletonized effect shown in the
figure. The insect enlarged is shown by fig. 39, while the cocoon

illiliiiiSKv

Siiii

^^^'''■W'M^mm^"M

J

■1^^^

gBiiiiS

sfag-

^p^

iiiiiiirtMar-..:.

^^^^^^^^^^1;'

IT

85

from which the acliilt moth has escaped is shown b}^ fig. 40. In
escaping^ the moth pushes off a little round lid in the cocoon.

There is another member of the same family which^ when full
grown^ is somewhat larger^ of a bright yellowish green with a
peculiar brown marli upon the back and having a double row of
tubercles on either side from wliieh grow tufts of bristles or spines
very much like those described on the hairy caterpillar of the
family Lymantriidce. This caterpillar^ shown enlarged by fig. 4.1,
has habits similar to those of the other species of Eudeidce^ except
that it eats holes in the leaf as shown by fig. 42.

This insect in the larval stage is attacked by a little hymenop-
terous parasite which lives within the body^ devouring the fat and
finally the internal organs of the caterpillar. When this parasite
has reached the stage for transformation to the pupa, it spins its
white silken cocoon within the caterpillar's body, and the latter
may often be found dead upon the leaf, looking as though it were
still alive but motionless.

Inasmuch as these three insects, like all caterpillars, obtain their
food by biting, they will be susceptible to any poison which may
be placed upon the leaf and which they can take into the mouth.
Among the many insecticides prepared for this class of insects,
those which are among the best are arsenate of lead, Paris green, and
hellebore, the first named being probably the cheapest and most
effective. When once the solution of arsenate of lead is dried upon
the leaves it will withstand rain for some time before it is finally
washed off, and it is doubtful if it would be all removed before the
insects would have secured a sufficient quantity to kill them. As
obtainable in the United States the arsenate of lead is a commer-
cial compound, but it can be made in the quantity necessary by
following the directions for its preparation in the chapter on in-
secticides. The preparation and use of Paris green, with other
useful insecticides, will be treated in the same chapter.

Of the family Ghnjsomelidm, there has been found at least one
species which does damage to the leaves of the cacao. As this
beetle is very small and of an obscure color it might be readily
overlooked when searching for insects upon the plant. The female
is about 4.5 mm. in length, is of an oval form and very much
rounded upon the back. The male is smaller, being 3.5 mm. long.
These insects vary from light to dark brown, the majority being
a very dark brown. The wing covers are very glossy and are marked

36

by longitudinal dotted lines extending from the base to the tip.
The adults are quick in their movements^ both when walking and
flyings taking readily to wing when disturbed or dropping quickly
to the ground. They are very difficult to catch unless a bag is
held beneath the leaf upon which they are resting and the latter
be shaken. Even then, upon alighting in the bag they will almost
immediately fly away unless promptly killed. The eggs of these
insects have not been found, but as with most beetles pertaining to
this family, they are probably laid upon the lower sides of the
leaves in patches in which the single eggs stand on end. The young
grubs are very peculiar in form, being shaped like the larvae of
ladybirds, Goccinelidce, except that their abdomens are thicker at
the rear. They move very slowly, and when disturbed cling to
the surface rather than drop to the ground. Their bodies are cov-
ered with short black spines as a means of protection.

When young, these insects feed only upon the lower epidermis
of the leaf, but as they grow larger they eat away both upper and
lower skin, leaving a few of the larger veins which are too tough
to be eaten. The adults as well as the larv^ are leaf feeders, eating
through the entire substance of the leaf.

As many as twenty of these beetles are sometimes found upon
the same leaf, and as each consumes an area equal to about ten
times that occupied by its body, it can be readily seen that the
damage done by the cacao leaf -beetle is considerable. For the com-
bating of these insects a spray of arsenate of lead is recommended
as fatal to both larvae and adults.

Further observations are necessary in order to determine where
these insects pupate. Most of the leaf -eaters pupate in the crevices
of the bark and in dried leaves and other secluded places, such as
wounds in the trees and rubbish which accumulates around the neg-
lected ones, and doubtless those of cacao have the same habits. Fig.
43 represents the full-grown beetle, a being the male and h the
female, both much enlarged. Fig. 44 shows the larva of a related
species.

SCALE INSECTS.

Cacao leaves are affected by at least two species of scale insect.
This is an insect which, in the larval stage, exudes a waxy secretion
which forms a shell or scale which soon completely covers the
individual so that none of its body is visible. This is of peculiar

Fig. 43.

37

f orm^ according to the species. Some species are long and narroW;,
others are elliptical^ oval^ or circular^ others oblong. Usually there
is a prominence near the center called the nipple of the scale. The
scale of the adult contains the successive exuvias which have been
shed by the young in its transformations. Only the adult females
are found beneath the scale. They are legless^ wingless, rounded
masses with no eyes. Their mouth-parts consist of a very fine
filament composed of three parts. This is inserted into the sub-
stance of the leaf or through the bark, and by this means the
insect obtains her nourishment. Once fixed in a certain spot upon
the food plant, she never. moves and probably never removes her
proboscis from the place where it is first inserted. She lays her
eggs under the scale and the young come forth from beneath it to
begin their own independent existence. The hinder end of the
f emale^s body is composed of a series of what are called anal plates.
These are portions of chitine, the hard material found in the walls
of all insects^ bodies. They are lobed, and between the lobes are
arranged series of bristles or spines. The form, number, and posi-
tion of these plates are characters upon which are based the classi-
fication of these microscopic insects. Very frequently the food
plant of the scale is used as an aid in its determination, but this
is variable, as there are certain scales like the San Jose scale,
Aspidiotus permciosus Comst. and the oyster shell-back louse, Mijtil-
aspis pomorum Bouche, which have a variety of food plants. The
male larva of the insect forms a scale as does the female, but when
it reaches the adult stage it comes forth a winged insect similar
in appearance to the one shown by fig. 6 of the frontispiece. A
young scale insect with its legs and other parts of the body complete
is shown by fig. 4 of the frontispiece. At certain seasons these
minute insects may be seen crawling around upon the infested
leaves or twigs, but they soon settle, usually within a few days.

It is impossible to observe or attempt to study this class of
insects without the aid of a fairly good hand magnifying glass.
They are so small and have so little of the appearance of insects
as we usually know them, that they would scarcely be taken for
such by persons not familiar with the subject. For this reason
they are enabled to gain a good foothold and to multiply to very
great numbers unless checked by some natural enemy. In connec-
tion with the question of their multiplication it may be said that
these insects, like Aphids, multiply with very great rapidity and

38

in numbers which are simply astonishing to those not familiar with
their habits and life history. It is claimed that a single pair of
the San Jose scale will in the course of a summer in the United
States become the progenitors of more than three billion offspring.^
Thus the cacao which might be slightly infested with scale at one
time might very shortly thereafter be completely covered.

The first of the scale insects found upon the cacao^ the sisi scale,
so named from its resemblance to a Filipino oyster so called in
Visayan, is black, shiny, and has the shape shown in fig. 45. It
has thus far been found only upon the upper side of the leaf near
the midrib. It is very slightly convex. Upon reversing the leaf
a yellowish spot can be seen beneath the spot where the scale is lying.
This is caused by injury to the leaf tissue, a result of the insertion
of the insect^s proboscis.

The combating of scale insects has presented one of the most
serious problems which has confronted not only the grower of fruit
and other trees, but also the economic entomologist, du^ring the
past few years. All kinds of remedies have been tried, such as
kerosene, crude petroleum, whale-oil soap, hydrocyanic acid gas,
lime, sulphur and salt wash, as well as patent articles, all of which
contain some one or more of the above ingredients. Even now
it is extremely difficult to say with any certainty which of these
remedies, or whether any of them, will prove best adapted to the
needs of the cacao grower who finds his trees threatened by this
liviL No experiments have thus far been made anywhere in the
Philippines with this class of insecticides with reference to the
treatment of the scale insect, owing not only to the lack of the
proper materials and also to lack of the machinery for their appli-
cation, but also, thus far, to lack of opportunity to devote to this
very interesting and important subject.

INSECTS ATTACKING THE FRUIT.

CACAO MEALY BUG.

Many plants in the Philippines, as elsewhere, are attacked upon
their leaves, branches, and fruit, by several species of insects known
as mealy bugs. These insects belong to the same family as the
scale insects, the CoccidcBj and their effects upon the cacao are
only second in importance to the work of the cacao borers.

iBuL 3, n. s., p. 44, U. S. Dept. Agr., Div. Ent.

39

Going through a cacao grove at the time when the trees are in
fruit one notices many pods which seem to bear a whitish fungus-
like material. Upon closer examination the fungus-like growth
will be seen to consist of large masses of whitish insects. These
insects are 3 mm. long and 2.35 mm. broad and the bodies, which
are pinkish yellow, are covered with a fine powder-like substance.
If examined with a magnifying glass it will be seen that this powder
extends only to the sutures or joints of the segments and that the
latter may be readily counted even in those individuals which have
much of the powder. These bugs attack the fruit just after it
has set, and multiplying thereon with great rapidity, often cover
it entirely by the time it is ripe. They first begin in tlie depressions
or grooves and gradually spread upward upon the lobes of the pod.
They crowd together in large numbers and are invariably attended
by swarms of ants, whose purpose is to secure the honey-dew voided
by them. One of the most interesting examples of the interde-
pendence of insects is shown in the relation of the ants to these
plant lice. Upon certain pods it is a not uncommon sight to see
the valleys between the lobes of the pods completely roofed over
by a gray material, which upon examination proves to be a kind of
crude paper, formed from particles of the decayed wood of the
cacao tree. Small black ants will be seen running in and out
through the openings in these sheds, and curiosity upon the part
of the observer leads him to break away a portion of this material
in order to find out what, if anything, is beneath it. He is re-
warded by finding in the grooves thus protected, large numbers of
the white mealy bugs, with their young and with willing servants,
the black ants, attending and caring for them. The ants will be
seen taking individual mealy bugs in their jaws and carrying them
from place to place, and especially is this true of those which are
exposed to view by the destruction of tlieir roofs. The bugs submit
to this w^ith no sign of displeasure. If the observer watcli long
enough, he will see the ants building the roof or repairing the parts
which have been broken away. They manifest great uneasiness
wh6n disturbed and all those individuals which are under the roof
at the moment, come forth and assume an aggressive attitude, sitting
up on four of their legs with the front ones in the air and the
abdomen doubled under as if about to sting. They, however,
possess no sting and only assume this attitude in instinctive imita-
tion of those forms which do possess one. The author has found

40

cacao pods upon which all of the ten grooves were completely filled
with the mealy bugs and roofed over by the ants. A unique feature
of the fruit thus attacked was that one of the tunnels extended
to the fruit stem and along the limb to the tree and then down the
trunk to a spot where the ants entered a part of the tree which
was decayed. Upon opening this decayed wood the true nest of
the ants, with their young in all stages, was found. This would
seem to indicate that the tunnels or roofs are not built solely for
the benefit of the mealy bugs, but also as a protection for the ants
in going back and forth from their nests to the pods where their
^'^cows/^ as they are sometimes called, live. This double and some-
what intricate system shows, in a way, the wonderful provision of
ISTature whereby, through their inter-relationship, certain species
of insects are propagated and perpetuated. It is undoubtedly true
that without this provision either one or the other of the species
would soon be exterminated. In as far as these animals are related
to man and to his economy they must both be considered enemies,
the mealy bug as being directly injurious to the product of the
cacao, and the ant indirectly, as protecting and caring for the
mealy bug in order to secure the product of its attack upon the
tree. The latter must, therefore, share with the former in any
treatment looking to its extermination.

Little is so far known of the life history of this cacao mealy bug.
Its eggs have been discovered; the young have been found in
great abundance in the deeper grooves of the cacao pod. In the
frontispiece is shown a ripe cacao pod upon which the adult and
young mealy bugs with the adult male and female, the ants which
attend them, an insect parasite, and tunnels or sheds built by the
ants are represented. The openings of these sheds are regularly con-
structed so that the ants can go in and out at certain places without
disturbing the bugs. By whatever method these insects are treated,
the sheds would offer but little if any hindrance to the effects of the
insecticide, inasmuch as they are built of an extremely porous
material through which kerosene, crude petroleum, or other similar
material would soak very readily. Probably the very best solution
to apply to these insects would be the kerosene emulsion recom-
mended for plant lice on page 30. The bodies are fully as tender
and delicate as those of the plant lice and therefore the same
proportions of ingredients could be used. The sheds where they

41

are present would hold the insecticide longer in contact with the
insects' bodies and would thus be a help in the extermination of
the mealy bugs. Naturally the best time to spray the trees for
these insects is just after the fruit has attained the size of a small
hen's egg. If successfully subdued at this time the chances are
that they will not reappear.

The amount of injury that these insects inflict is shown in the
smaller size of the pods attacked by them^ the scars which extend
down into the fiber of the pods and the general inferiority in size
and quality of the beans or kernels themselves. Pods infested by
these bugs are not only inferior in quality to those not infested, but
they are also very unsightly to those who have to handle and open
them. I am thoroughly convinced that with sufficient care and the
judicious use of the spray pump and the kerosene emulsion of a
proper strength these minute pests may be entirely eradicated from
the cacao grove, and clean, healthy, well-filled pods will be produced
where now inferior ones exist.

There is another species very similar to the mealy bug, which
has been found upon the cacao in a few instances. It is also quite
prevalent upon the nangka, Artocarptts integrifolia Linn., being
situated on the fruit stem and often on the small twigs. It is
covered with a thin, white or yellowish-white incrustation which
breaks very readily upon being touched, however lightly. As this
insect has been found only in a few instances and on trees which
were in close proximity to nangka, it is probable that it will not
naturally attack the cacao. However, it would be well to be on
the lookout for it. Further observation will reveal the facts with
regard to its preference for cacao and its life history and habits
may then be discussed at greater length.

BENEFICIAL INSECTS.

There are few trees which have a host of enemies without at
least a proportionate number of friends in the insect world, and
the cacao is no exception to this rule. In many cases the insects
which in some way or another prove beneficial to the cacao are not
found solely upon this tree. This does not have reference to the
parasites of the insects which affect the cacao, but includes such
insects as wasps, aphis-lions, ant-lions, and spiders, the latter not
being insects in the technical sense.

42

WASPS.

x^iiiong wasps which are found upon the cacao and which are
known to feed upon larv^ and adults of noxious insects may be
mentioned the alingayo and the amomo-ong, called here by their
Visayan names. The former belongs to the true wasp family^
the Vespidw, and, the latter more strictly to the hornets. The
alingayo, which is familiar to all who live in the Visayas, because
of its very sharp and severe sting and the fact that it often builds
its nest in houses^ is not more than 13 mm. in length. It is of a
light brown color with transverse bands of yellow upon the abdomen
and diagonal ones upon the thorax. The second segment of the
abdomen is as long as all the other segments together and when
at rest the insect retracts the hinder segments within this long
one^ giving it a very shorty stubby appearance; but when angered
and about to sting it can increase the length of the abdomen more
than twice the normal size. A broad band of yellow borders
the hinder edges of the second abdominal segment^ which is of a
deeper brown than the rest of the body. The stinging instrument
is very sharp and about 2 mm. long^ curving slightly downward.
The eyes are slightly yellowish, the antennae are broken or Jointed
at a distance from the head of about one-third of the entire length,
and they droop forward in front of the eyes. When at rest, this
insect folds its two pairs of wings down between the thorax and
abdomen and thus they lie for a part of their length below the
abdomen as shown in fig. 46 d. The general appearance of this
insect is given in the same figure at &. This insect builds a nest
like the one shown by fig. 47. It is often as large as a man^s two
hands and every cell contains a grub or a pupa. The larvse are
fat, white grubs with no sign of legs, eyes, or other appendages,
and they feed upon the masticated and partly digested insects
which the adult brings to them. Fig. 46 a shows the full-grown
grub and fig. 46 c the pupa, which has been removed from its cell
and from the delicate silken cocoon which was spun before its trans-
formation. Soon after changing to the pupal form, the insect is
a creamy white, but as the process of development goes on it
assumes a darker color, beginning at the eyes, which are the first
to show evidence of the true color of the perfect individual.

These insects have been seen to 'capture small caterpillars and

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43

to gradually chew them into a soft mass which they carry in their
jaws to their nests. They feed upon other insects and do not
disdain flies. It is estimated that a colony of 100 adults will destroy
in a month more than 3,000 caterpillars and other insects. Pig. 46
shows the larva, pupa, and adult of this interesting and useful little
wasp.

The amomo-ong is very much larger than the alingayo and is
one of the most beautiful wasps which I have ever seen. It is 30
mm. long and 7 mm. wide, of a Jet black with three transverse
bands of orange red, one on the upper part of each of the first
three abdominal segments, the second being about thrice the width
of the first and third. The head and thorax are of a dull velvety
black. The compound eyes are black and glossy and in the top
of the head are three little black glistening ocelli, or simple eyes,
forming a triangle. The wings of this beautiful insect are of a
reddish brown, the fore wings measuring 23 mm. in length. They
are somewhat smoky. They extend beyond the tip of the abdomen.
The antennae are elbowed, as with the alingayo, and droop over
the eyes. The legs and feet are of a color uniform with the body
and are provided with claws for grasping the surface upon which
the insect rests and for obtaining its prey. These insects liave
the same habits as the alhTgayo, but instead of building a flat
nest with all the cells in the same plane, their nest has the appear-
ance shown in fig. 49. Eig. 48 shows the adult. With this nest
were captured some eight adults, about half those present, the rest
escaping in my attempt to get them. These insects are valiant
protectors of their homes and their young. They will remain in
the nest even when struck at with poles, one or two of them darting
at the intruder. When the nest has been torn away they will even
come back to the same spot and attempt to build another in its
place. This is contrary to the usual habit among insects, of giving
up a place when once their nest is damaged or destroyed. That
these insects render a valuable service in the destruction of larvse
of injurious species is beyond question of doubt. They have been
repeatedly caught when returning to their nests with full grown
larvae in their claws. They carry their prey in their claws rather
than in their jaws, as is the case with the alingayo^ and they do
not masticate it until they reach their nests.

Among the species of caterpillars which have been taken away

44

from these wasps are those of Geometridce, LymantriidcB, Getonia,
and Tortricidce in large numbers. In all cases where they are not so
numerous as to prove annoying by stinging unsuspecting workers
among the trees^ they should be left alone in their nests.

RED CORSAIR.

x\nother insect which is frequently met with upon the cacao tree
and which might be mistaken for its enemy is one of the true bugS;,
a Eeduviid which I propose to call the ''red corsair/' This Hem-
ipteron belongs to a class of insects which are very properly called
assassin-bugs^ because their instinct is directed to the killing of
other insects. The red coi^sair, a picture of which is shown by
fig. 50, is a very showy insect, having a black underbody with red
thorax and red wings. The head and feet are black, as are the
antennae. The insect measures Yi mm. long and 5 mm. wide. The
head, which is very long and narrow, has a peculiar beak which
curves under toward the thorax. This beak is very sharp and is
used for sucking the blood of insects which the red corsair captures.
At a is shown a dorsal view^ of the insect, while at h it is shown
enlarged twice with the beak visible. The nature of the beak can
be readily seen from the drawing.

This insect moves very stealthily about upon the surface of the
leaf and pounces upon whatever insect it may find. It has been
observed most frequently feeding upon geometrid caterpillars which
it holds between its fore-feet while sucking their blood. When not
seeking its prey, it rests quietly with its legs spread far apart and
the body suspended above the surface upon which it is standing.

If caught in the fingers this insect is liable to inflict a sting
with its beak which, while not poisonous, is very painful to say the
least, and with some persons the result may be a disagreeably sore
swelling. They do not, however, need to be handled and the good
they do on the trees in the matter of destroying noxious insects is
of incalculable value when compared with the occasional bites they
may inflict on those who carelessly manipulate them. Their eggs
are laid in crevices of the bark and when the young come forth they
look very much like the adults, save that they have no wings. The
young also feed upon small larvae and other insects. Stal in his
^^Hemiptera Insularum Philippinamm,,^ ^ calls this insect Sphodro-
nyttus erythroptertis Biirm., var. conviims Stal.

Fig. 50, a and b.

45

ANT-LION.

In a cacao plantation in which the top soil is sandy and in which
there has been no rain for some time^ one will very frequently see
around the bases of the trees a number of cone shaped pits with
the sides, which are composed of loose sand thrown at an angle of
about 45° to the surface of the ground^ coming to a point below.
If an ant or a fly be tied to a string and let down into the bottom of
this pit it will be at once seized by a pair of jaws which is lying
concealed in the saiid. If the observer be quick enough he may
succeed in jerking out a peculiar-looking grey insect resembling a
large-sized louse, and in fact so called by the Visayans, who name it
cotu-cotu, meaning a big louse. This animal which measures, when
fully grown, 12 mm. long and 5 mm. wide, is the larva of a very del-
icate and beautiful insect of the family Myrmeleonidw of the
order Neuroptera. The adult measures about 29 mm. in length and
has an expanse of wings of about 60 mm. The wings are irides-
cent and the general color of the insect^s body is a smoky grey.
The eyes are rather large and spherical, being prominently set, like
those of the damsel flies, relatives of the dragon flies ; or, as they are
called in Visayan, tumhuc-tumbuc. One would never associate
this delicate insect with the voracious cotu-cotu.

The larva has habits which are as strange and incongruous as its
appearance. Its two forcep-like jaws are well adapted to sucking
the blood of unfortunate insects which drop into the pit which it
has dug for them. It invariably moves backward instead of for-
ward. If dropped upon a sandy spot it almost instantly disappears.
It uses its tail as a sort of shovel to dig its way into the ground.

Its method of constructing its pit is interesting in the extreme.
After working its way below the surface it begins to move around
in a circle, the diameter of which is in proportion to the size of
the insect and consequently in proportion to the hole which it will
finally have excavated. When it has completed its circle, it begins
throwing out the sand with its head, which serves as a shovel. As
the sand is thrown out the larva gradually moves toward the center
of the pit which, from the force of the caving sand on the sides-
begins to assume a conical shape. When the ant-lion, for such it
is called in English, encounters a pebble or small stone it imme-
diately lifts it upon its opened jaws and attempts to throw it out.
It can throw out a stone which weighs much more than its body.

46

When the pit is completed the ant-lion goes into the sand at the
apex of the cone-shaped hole^ and with only its jaws and its eyes
protruding^ awaits the coming of some unwary insect. It usually
has not long to wait^ for as a rule ants and such crawlers are very
curious when they come to a hole. They invariably like to inves-
tigate^ and peering over the edge of this pit they lose their balance
and begin to slide down just as a boy would if playing at the top
of a sandhill. Their downward motion is very much accelerated
by the ant-lion^ which immediately begins to throw sand up over
them. This takes the sand away from imder their feet;, and in
a. shower of the material they are gradually forced down into the
pit. Finally, reaching the bottom completely exhausted, they are
seized upon by the skillful foe, dragged under the sand, and their
blood is sucked out. Afterwards their dried skins are flung out of
the pit by the ant-lion.

Fig. 51 shows two views of the ant-lion^s nest, one being sectional,
with the insect seen at the bottom. Fig. 51 a shows the larva.

The ant-lion will not attack large insects such as beetles or big
spiders which occasionally fall into its pit, but remains quiet until
the intruder can get out. It will attack the termite, any kind of
ant, small flies and bugs which fall in, and it has been seen to drag
small moths under the sand. When ready to pupate, the ant-lion
spins a spherical cocoon of grains of sand fastened together by a
beautiful, pearly white silk, and lined with this material.

This insect can certainly be called a decidedly beneficial one.
for of all the insects which it has ever been seen to capture not
a single one was other than noxious, and the number of ants and
anay which it catches and kills in course of its somewhat lengthy
larval stage must be great indeed.

PRAYING MANTIS.

To the ortliopierous family Mantidce belong several very pecu-
liar-looking animals which from time immemorial have received the
attention of even the most careless observers. They are called man-
tis, deviFs riding-horse, camel-horse, mule killer, etc., in English,
and tagd-tagd in Visayan. In Tagalog they are known as sa-samhd.
Unlike most Orthoptera, they are carnivorous, living upon other
insects, and are therefore to be classed as beneficial.

They lay their eggs upon the twigs of the cacao and other plants.

47

and as many as 200 of the young hatch from an egg mass such as
shown by fig. 52. The young are very much like tlie adults in ap-
pearance. Fig. 53 shows a young mantis and fig. 54 an adult. The
forelegs are fitted for grasping the prey. These insects often remain
motionless upon a twig for several hours^ but if an insect comes
within reach^ they immediately^ with great rapidity^ grasp it in their
forefeet and proceed to eat it^, only rejecting' the harder parts and
the wings. After feeding they very neatly clean their faces^ antennae,
and front feet and again begin their watch. They run readily and
are also good fliers. They rest entirely upon the two hinder pairs
of feet. They have the habit of sitting up and watching the ob-
server^ who in turn becomes the observed. The large eyes and
peculiarly shaped head, together with the large body, make them
objects of very grotesque appearance.

SPIDERS.

The many kinds of spiders which live upon the cacao and which
undoubtedly do it a service by the number of insects which they
capture and devour, should be the subject of special attention,
although they do not come under the technical classification of
insects.

Among those which have been found most abundant are the
orb weavers, the jumpers, one species of tarantula, and many
species of the crab spider, or Thomisidae. Perhaps the most pe-
culiar and one of the most beautiful of the orb weavers is the
crescent spider, which is ilhistrated by fig. 55. It has its abdomen
shaped in the form of a perfect crescent, is of a beautiful jet black
and yellow, and the horns at the sides of the abdomen are pubescent
at their tips. This spider builds a true orb web and catches many
insects, the most of which are harmful to the plant. Among these
have been noted plant lice, moths, plant bugs, and small CoJeoptera,
like ScoIyUdce, ChrysomeMdw, and Scandjaeidw, all harmful species.

The crab-spiders are so called because of their resemblance to
crabs in form and arrangement of the legs. They ai'e of a light
color, usually like that of the flowers which they inhabit, and they
lie concealed in the clusters. They seize plant lice and other small
insects as they come to the flowers. Undoubtedly they occasionally
capture beneficial insects like hymenopterous parasites.

The majority of spiders found upon the cacao belong to the

48

jumpers or Attidw. These spiders are sure to attract the attention
of the observer because of their peculiarly beautiful and varied color-
ings and their activity. They are light green^ golden yellow^ brown
and red, blacky grey, and of many other and striking colors. They
are extremely active, jumping forward, or backward, or sidewise
with equal celerity, and they invariably capture their prey by
pouncing upon it. Their eyes glow with what appears to be an
internal fire, and the position on the head and the form suggest in
a most remarkable way the headlights on an automobile.

A most peculiar and common form of the Attidce is the ant-like
jumper. These insects vary in length from 3 to 10 mm., according
to the species, and their resemblance to black ants is so very great,
not only in their form but in their movements, that they often
deceive the close observer. They run upon only six legs, carrying
the two fore legs high in the air and moving them with the same
uncertain motions that ants have when using their antennae. They
will run a short way, then stop and wave their front feet, then start
off sidewise, then back, and before one knows what they will do
next, have pounced upon some unsuspecting fly or bug. In form
and movements they really represent one of the most striking cases
of mimicry. Fig. 56 shows an example of the ordinary jumping
spider and the ank-like form.

At the base of the cacao one frequently sees a hole 15-20 mm. in
diameter, carefully and neatly lined with snowy white silk which
sometimes extends out upon the ground for some little distance. If
one will dig out this hole, following its twists and turns, at the
inner end, which is usually 40 or 50 cm. in the ground and par-
allel with the surface, if the ground be level, or horizontal if the
hole be in the side of a hill or a mound around the tree, he will be
almost sure to find a most beautiful dark brown hairy spider of
the tarantula family, Theraphosidce. This spider measures when
extended, including legs, 85 mm. in length and 65 mm. in breadth.
Its brown velvetry coat appears almost black when it is seen curled
up against the white background of its silken cell. If one of these
spiders be examined when dead, it will be seen to have two very
strong, curved, brown forcep-like mandibles which, instead of ap-
proximating point to point as in most spiders, are bent forward
and downward so that the tarantula can not really grasp its prey
with its jaws. It is, however, provided with two foot-like palpi,
which serve to hold its food while it is eating. These palpi give the

Fig. 55.

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49

tarantula the appearance of having 10 legs instead of the true the
number, which all spiders have, namely, eight.

The area around the mouth is covered with golden reddish hairs.
This characteristic seems to be common to members of the taran-
tula family. The spider feeds upon most kinds of insects; the
exuviae of various larva3 and pupa,' being found in some of the nests
opened. It seems to show a great preference for cockroaches, skele-
tons of several kinds having been found in its abode.

PESTS OTHER THAN INSECTS.

A word should be said before concluding this paper regarding
some other animal pests of the cacao. In all parts of the world
great trouble ]ias always been experienced in cacao growing because
of the ravages of rats and mice. These rodents, working at niglit
when vigilance is relaxed, often do an incalculable daiuage to the
fruits, destroying many pounds of the nuts in a season. Fig. 57
shows two cacao pods, each with a hole in the side just large enough
for the small rodent to enter. The intruder very skillfully removes
all the kernels from a pod and leaves it hanging on the tree, where
it dries, if not removed hy the grower.

JSTo effective remedy has been devised for this pest, but the writer
would suggest that an excellent one can be found in the discarded
pods after the ripe nuts have been removed. The pulp on the
inner side of the pod being scra])ed out and uiixtnl with some kind
of effective poison like arsenic or paris green, is replaced iii small
quantities in each pod. The pods are then to be fastened together
with two bamboo toothpicks and the decoys placed beneath the
trees, two or three under each one. It is more than likely that
the rats, finding these upon the ground, will attack them first, and,
gnawing into them, will eat the sweet pulp within. The results will
then remain to be seen, but certainly tlie cbances of success are verv
much in favor of the growers. All hogs and other domestic animals
should be excluded from plantations in which these experiments
are being tried and the refuse should be collected as soon as it is
seen that the pods have been gnawed into by the rats, and it should
be buried at a sufficient depth to insure its not being dug up by hogs,
etc. As the pods are liable to shrivel and open during dry weather,
they should be renewed from time to time as occasion will require.
10852 4

50

INSECTS ATTACKING DRIED CACAO.

Very little can be said at present concerning insects attacking
the dried product of the cacao, namely, the beans and husks. In
visiting various wholesale establishments for the handling of cacao
in Manila, beans have been found giving evidence of the work of
some form of the common dried-fruit moths, but thus far neither
the larvae nor the adults have been discovered.

Chittenden, in his bulletin on ^'Some little-known insects affect-
ing stored vegetable products,'^ ^ says the following in connection
with a moth which he calls the "chocolate^' moth. I would, how-
ever, suggest that instead of being called the ^'^chocolate'^ moth it
be called the cacao-bean moth, as it is more frequently found in
the bean than in the manufactured chocolate :

llie habits of our flour and meal feeding phycitids, Ephestia kuehniella
and Plodia interpunctella, are so well known as to necessitate no further
comment here, but there is still a fourth moth which, although represented
in our faunal lists, seems never to have received mention as an injurious
species in this country. I refer to Ephestia eluteUa Hbn. Its habits have
been known in Europe since early in the last century, yet so far as I know
at present, American records show nothing positive regarding injuries.

Reaumer's account of the moth that injures chocolate, published in 1737,
is generally conceded to refer to the present species, and as it is this species
that is most often associated with the chocolate nut of commerce it may be
called the chocolate moth. Recent study of bred material shows this to be
the moth mentioned in Insect Life (Vol, IV, p. 332) as having been received
at this office from Mr. H. F. Wickham, who found it injurious to cayenne
pepper in one of the drug houses at Iowa City, Iowa. We have also speci-
mens bred from dried apples obtained from a New York City dealer and sub-
mitted to this office by the Division of Chemistry, and others from cacao
beans received from Mr. C. A. Barber, who obtained them from Montserrat,
West Indies. According to various European authorities, this species also
attacks manufactured chocolate, coffee and various dried fruits, and even
does considerable damage to ship biscuit, which it injures after the manner
of E. kuehniella.

It may prove that the above-mentioned species is the one which
has been found in the cacao in Manila, and the possibility is more
strongly emphasized by the fact that the condition of the beans,
the class of holes made, and the frass contained within the beans
all point to the work of a phycitid.

Certain beetles of the families Tenehrionidw, cadelles, or dark-

iRul. No. 8, n. 8., p. 9, U. S. Dept. Agr., Div. Ent.

51

ling beetles, and the Nitidulidce or sap beetles, are also found in
stored cacao products as well as in decajdng or over-ripe fruits
and on wounds in trees, the sap of which they suck.

For these insects, as for all insects which are found in sto]-ed
products, it is difficult to suggest an effective preve]itive, inasmuch
as they find such ready means of entrance through the meshes of
the sacks. Even where the adult insects can not themselves get
into the bags and sacks, instinct seems to lead them to lay their
eggs upon the outside, and the tiny larva, upon hatching, find easy
ingress. Once inside, the insect passes through its transformations,
but upon becoming adult it can ]iot escape and continues to
multiply.

Frequent handling of the contained cacao and a careful shaking
of the bags, afterwards placing them in bright sunshine, renders
the cacao less liable to be attacked by any form of insect Avhich
would eat the dried nut.

Where prevention has failed, or where infested cacao is received
by the dealer, the best plan is to submit the full sacks, or better, if
possible, the exposed contents, to the fumes of carbon bisulphide in
a closed bin or other absolutely tight receptacle. Tf an air-tight
room can be had, the sacks may be left in it for two or three days
or even longer without any harm being done to the beans, and
with the perfect assurance that all insects contained therein will be
destroyed at the end of that time. The bin or room should then be
opened and thoroughly aired and the cacao spread out in a draught
or in the sunlight.

Under no conditions should a lamp or other light be permitted in
a room where the carbon bisulphide is being used, nor should per-
sons remain in the room. If a bin be used, the bisulphide may be
put on top of the cacao in a small dish, allowing 30-40 grams for
every cubic meter of space. As the bisulphide is heavier than the
air and very volatile, it will evaporate quickly and settle downward
in the bin, suffocating all insects therein. If a room be used the
vessel may be put upon a high shelf or upon some object so that it
will be as near the ceiling as possible. In this way the entire room
will be fumigated.

DISEASES AFFECTING CACAO.

Although the question of plant diseases such as fungi, rust spots,
mould, and rot do not belong in the province of entomological

52

investigation, the fact that these diseases were given some attention
by me during my study of cacao insects will warrant my saying a
few words about them and suggesting means for their prevention
upon the leaves and fruit of this valuable plant.

There are four types of fungus attack which have been most
frequently met with, namely, cacao leaf-spot, cacao leaf-blight,
cacao pod-spot, and pod scab. The first of these diseases attacks
the leaf in spots as suggested by the name. (See hg. 58.) These
spots are irregular in shape and in an advanced stage are a dull
whitish grey as though the leaf had been scorched to an ash at the
point, which dries and breaks of!. The two types of fungus dis-
ease which attack the pod are very characteristic and will be recog-
nized by the growers at once, as those represented in fig. 59 and
fig. 60. Both of these attack the fruit in all stages of its growth.
The pod spot occurs in spots similar to that which attacks bean pods
in the United States. The spots soon completely cover the affected
pod and not only cause a very unsightly growih, but also mate-
rially affect the development of the fruit. Fruits which are thus
affected are smaller and the beans are found to be misshapen and in
some cases not developed. The history of this disease, its causes,
and morphology are yet to be investigated.

The pod scab is undoubtedly the worst form of disease which
attacks the cacao. It is recognized in its advanced stages by the
fact that the pod becomes dry either upon one side or over its
whole surface. It then cracks open in unsightly gashes as though
hacked with a knife. Of course the contained beans in such pods
are worthless. This is another disease of which the causes are
not clearly known.

Although diversified in their modes of attack, it is undoubtedly
true that the same means of prevention will apply to them all
since they are fungoid or bacteriological in character. Many thor-
ough tests covering a period of several years have demonstrated
the efficiency of a mixture of copper sulphate (blue vitriol) and
quicklime, commonly called Bordeaux mixture, for nearly all kinds
of fungus diseases affecting plants. The blue vitriol is the fungi-
cide or destroyer of the fungus spores, and the lime is added to
keep the vitriol from burning or scorching the leaves or fruit.
This solution, a formula for which will be given under ^Tnsecticides
and fungicides,^^ will of course have to be applied to the trees by
means of spray pumps and a very fine spraying nozzle.

Fig. 59.

-';\'; ^

fe^-V^V^- ;''/*/,;'-.'?;•

A

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53

The writer is well aware of the fact that in the limited time
during which he has studied the questions of insects and diseases
of the cacao, many forms and conditions liave escaped his notice,
but as this is only a preliminary bulletin and issued so that the
grower may have something at hand to guide him in the recognition
of and dealing with the most important pests, the fact that all
pests are not treated will not detract from its usefulness. He
would be under great obligations to all growers of cacao to whom
this bulletin shall come if they will send him suggestions of inethods
which they have tried with success.

There is a disease called "die-back" mentioned by Lyon in his
bulletin on cacao, which I have not found in the Pliilippines, and
I would be grateful for specimens showing this disease.

The production of cacao has such a favorable future in these
Islands that any measures which will tend to a better degree of
cultivation and a more thorough protection of trees from unneces-
sary ravages should be welcomed by growers and prospective
growers throughout the Archipelago.

SOME INSECTICIDES AND FUNGICIDES.

TJIEIK USE AND PKEPAKATION.

Insecticides and fungicides have for their object tlie prevention
of the attacks of insects or fungus diseases or tlie Ivilling of forms
already present, either upon the jdant or otiier substance atfected
by the insect or the disease.

With reference to insects there are two kinds of insecticides, the
internal and tlie contact. Of tlie latter there are the corrosive
poisons, which destroy the substance witli which tliey come in con-
tact, and the sutfocating poisons, which act upon the breathing
apparatus, producing suffocation.

Internal poisons are those which are intended for tlie insects
which eat the substance of the leaf or other part of the plant.
Applied to the surface of the leaf either as a powder or as a
solution they are taken by tlie insect along with its food, and, acting
upon the alimentary canal and other internal organs, accomplish
their work.

Contact insecticides are those which, coming in contact with the
body of the insect, produce a condition, usually like that caused by
k corrosive, which results in death. To this class ])elong ashes, lime,
Ivcrosene, carbolic acid, crude petroleum, pyrethrum, and smoke.

Suffocating poisons are those wliich, entering the tracheal', either

54

clog them up or paralyze the muscles of respiration^ thus killing
the insect. To this class belong carbon bisulphide^ napthaline^
bezine, petroleum, kerosene, whale-oil soap, and the fumes of hydro-
cyanic acid gas.

Among the most important of the internal poisons are those which
have as a basis some form of arsenic. This substance in any form
is deadly to all animal life. As there are many forms of arsenical
insecticides, only those which are considered as of value in connec-
tion with the combating of cacao insects will be mentioned.

Arsenate of lead. — This insoluble chemical compound is prepared
as follows :

Grams.

Lead acetate 200

Sodium arsenate 50

Dissolve each ingredient in 16 liters of water separately in
wooden or stone vessels. Then pour these at the same time into
a barrel or tank containing 450 liters of water. The mixture
should be stirred constantly and rapidly while making. Inasmuch
as the compound which is formed (arsenate of lead) is insoluble
it is precipitated as a white powder and must be kept in suspension.
In order to make this mixture stick well on the foliage to which
it is applied about two and one-half liters of glucose or grape sugar
should be added to it before spraying.

A commercial compound of arsenate of lead mixed with glucose,
in the form of a thick white paste, is sold in kegs in the United
KStates, one form bearing the trade name, "disparene.^' Thi*s in-
secticide possesses all the good properties of that made at home by
the grower, with the advantage that it is mixed and ready for use
upon the addition of water in proper quantities. This has proven
one of the most cifectual and therefore most economical of insecti-
cides against insects preying upon the foliage of fruit, shade, and
ornamental pkmts.

Pa^is green. — This is a copper arsenite-acetate and contains from
55 to 60 per cent of arsenious acid. It is a bright green powder,
very heavy, and hence does not stay suspended in the water of a
spray pump unless continually agitated. iVs it does not dissolve in
water it is not liable to "burn^^ the foliage. If, however, twice the
amount of freshly slacked lime be added to a given qiiantity of paris
green, one can be sure that all danger from free arsenious oxide will
be averted and there will be no /^burning^^ of the foliage of the most
delicate plant.

55

Paris green would undoubtedly prove an excellent poison for
mice if applied, mixed with meal or bran, and the pulp of the
cacao in the manner mentioned on page 49. The proportion should
be one part of the paris green to fifty parts of meal or bran.

In using paris green as a liquid insecticide it is applied as fol-
low^s :

Paris green _. grams.... 450

Lime (fresh slacked) do 900

Wate" liters... 1,500

This is a clieap insecticide, is in universal use, and if care is
used to keep it in suspension in the water while spraying, it will
give as good results as any insecticide of its class.

ISTumerous other arsenates are sold under the following names,
and others: White arsenate, pink arsenate, white arsenoid, parine
green, laurel green, London purple, paragrene, and green arsenoid.

Kerosene. — This is a refined product of petroleum which is so
well known as to render a description of it unnecessary. Applied
pure, to any kind of insect, it immediately destroys life. It is
likewise fatal to plant life if undiluted. Used in a mechanical mix-
ture with water, it is a remedy against scale insects and plant lice.
A safer and much more effective preparation is the kerosene-soap
emulsion, which is prepared as follows:

Per cent.

Kerosene (9 liters) 67

Water (4.5 liters) |

Common or whale-oil soap (225 grams) /

Heat the solution of soap and water and add it boiling hot to
the kerosene. Churn the mixture by means of a force pump and
spray nozzle for five or ten minutes. The emulsion, if perfect,
forms a cream, which thickens on cooling and should adhere without
oiliness to the surface of glass. The above formula gives 13.50
liters and makes when diluted 120 liters of wash. (Report of the
entomologist: In Report of the Commissioner of Agriculture
[U. S.] for 1883, p. 152.) Another formula which may be of
interest is the following, taken from Dr. J. A. Lintner's Second
Kew York Report on Injurious Insects, 1885, page 38:

''Eight parts of water and one part of soft soap thoroughly amal-
gamated forms the lye which takes mineral oil and thoroughly
mixes with whatever proportions of the oil be added. As heat
aids much in quickly producing thorough amalgamation of the

56

ingredients^ boil the soap and water together^ and when ready^ turn
into ordinary wine bottles (costing little or nothing, especially in
the Philippines) which have been placed in boiling water. About
half fill the bottles, turning 125 c. e. of the oil into each bottle, then
fill up witli the boiling lye, cork at once and store away for use.

"When required for use a bottle of the mixture is pou.red into an
18-liter watering pot which is filled up with soft water, and is
ready for use, at a strength of 70 c. c. to 4.5 liters of water (1 part
oil to 64 parts water is about If per cent). Sevent}^ c. c. of oil to
4.5 liters of water is strong enough to kill aphides (the plant lice in
question) and such soft-bodied insects.

"By bottling the mixture as above, no mistake need be made in
using it of proper strength. ^^

Whale-oil soap. — A preparation made of fish oil with lye. Ef-
fectual against scale insects and plant lice, and when mixed with
carbolic acid makes an excellent deterrent for borers. When used
as a spray for plant lice the proportions should be :

Wliale-oil soap grams.... 450

Water liters.... 45-90

This should be thoroughly dissolved before using, and the weaker
solution is advised for trees when in young leaf. Even 450 grams
to 125 liters of water is not too weak. If ordinary soft soap or
turpentine soap be used the following are the proportions :

Common soap grams.... 450

Water liters... 18-36

Another excellent preventive which has been used most success-
fully against the peach borer in the United States and which would
probably prove of equal value to that of the carbolic wash is what
is known as the "Lime, coaltar, and whale-oil soap wash.^^ It is
prepared according to the following formula:

Unslaked lime kilos.... 25

Coal tar liters.... 6

Whale-oil soap kilos.... 6

The lime and tar should be slaked together with water sufliicient
to make the whole of the consistency of paint. The whale-oil soap
is dissolved in hot water and added to the lime and tar solution.
When water is added sufficient to make the whole mass as thick as
ordinary paint, it may be applied to the trees.

• ) i

Tohacco wash. — This very effectual remedy against plant lice has
certainly the advantage of cheapness in a country where tobacco is
abundant. It is applied as a spray after being prepared as follows :

Dry stems or tobacco leaf .....grams.... 225

Water liters.... 4.5

Steep over a slow fire for some hours^ then when ready to use it^
dilute the quantity with 200 to 400 liters of water.

Oarhon bisulphide. — This is a colorless liquid resembling refined
kerosene in appearance. It is of a very disagreeable odor and cx-
tremely volatile. It can not be handled around hres^ and even
smoking while nsing it is dangerous. It is explosive and also takes
fire very readily. Its vapor is lieavier than th(^ air, hence it shoukl
be placed above whatever it is desired to fumigate. In closed
bins or in rooms the proportions to be nsed are : 150 grams for
every 27 cubic meters, or 17 grams for every cubic meter. What-
ever it is placed into should be perfectly tight in order that the
fumes may not escape.

Bordeaux mixtw^e.— This valuable fungicide has as its essential
ingredient the sulphate of copper, commonly called blue vitriol, or
blue stone. It is prepared as follows :

Copper sulphate or blue vitriol kilos.... 1.80

Quicklime (unslacked) kilos.... 2.25

Water liters.... 225

The copper sulphate should be dissolved in half the amount of
water or 100 liters in a wooden vessel such as a half barrel. The
lime should be slacked in the remainder of the water, and when
ready for use the two solutions should be poured together into the
spray-pump^ barrel, or tank. In order to save time a stock solution
of each substance should be made and kept on hand.

First slack in a wooden vessel 22.7 kilos of lime. This should
be immediately strained into a barrel holding 225 liters and the
barrel filled with water. Cover the barrel to prevent foreign matter
from getting into it.

The copper sulphate stock solution should be prepared by dissolv-
ing 18.1 kilos of the crystal in 225 liters of water and putting it
into a barrel, covering the same.

When it is desired to use Bordeaux, take 22.5 liters of each solu-
tion and add enough water to make 225 liters of the Bordeaux mix-
ture.

58

SPRAYING APPARATUS.

At the present time the question of spraying in the Philippines
is a very serious one, owing to the fact that none of the goods of
large and reliable firms of spray-pump manufacturers are repre-
sented in the Philippine market. For several years past the
United States Government has carried on experiments for ascer-
taining the best apparatus for combating insects on a large scale,
and as a result of its work and the experimentation of individuals,
there are now upon the American market several very excellent
spray-pumps which, considering the ease of manipulation and the
fact that they will last for several years if given proper care, are
very reasonable in price.

The principal essentials of a good spraying apparatus are : That
it deliver a fine spray, that it keep the mixture to be sprayed in
constant agitation in order that the ingredients may be kept in
uniform suspension, and that it have sufficient capacity so that a
reasonable amount of the insecticide may be made and used at
one time.

The two types of spraying apparatus which would give the best
results in cacao plantations are the barrel pump, and the small
power spray pump. The former would be useful in small planta-
tions of not more than two or three hectares, and the latter for
large plantations. With a barrel pump and two nozzles, and three
men to operate it in the orchard, from 50 to 75 cacao trees could
be sprayed in a day. With the power spray pump a proportionately
larger number of trees can be sprayed. The best nozzle is one
which will break the liquid up into the finest particles possible and
at the same time is not liable to clog, or, if clogged, may be easily
cleaned.

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§3 aoanns oi3 bh 6145

UNIVERSITY OF MJtHIGAN

3 9015 0046

3959

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