PROPER, r OF

r-

I

LI B R ARY OF

IQ85-I056

Property of

1 C. EXPERIMENT STATION

P^ '-"rirnent of Entomology

t-

ECONOMIC ENTOMOLOGY

FARMIiR AND FRUIT-GROWER, AND

FOR USE AS A TEXT-BOOK IN

AGRICULTURAL SCHOOLS

AND COLLEGES

BV

JOHN B. SMITH, Sc.D.

Ftofessor of Entomology in Rulgers College ; Entomologist to the Neiv Jersey Agricultural

College Experiment Station and the New Jersey State Board of Agriculture ;

President of the Association of Economic Entomologists, of the Brooklyti

Entomological Society, and of the New Jersey State Microscopical

Society; Fellow of the American Association for the

Advancement of Science, etc., etc.

ILLUSTRATED

PHILADELPHIA

J. B. LIPPINCOTT COMPANY

Copyright, 1S96,

BY

J. B. LippiNcoTT Company.

Electrotyped and Printed by J. B. Lippincott Company, Philadelphia, U.S.A.

C O N T E N TvS.

r^ART I.

STRUCTURE AND CLASSIFICATION.

CHAPTER I.

PAGE

The General Structure ok Insects ii

CHAPTER II.
liiE Head and its Api-endages ...... 14

CHAPTER III.
Thorax and Abdomen 23

CHAPTER IV.
Muscles, Digestion, and Circulation . 27

CHAPTER V.
The Respiratory System 33

CHAPTER VI.
Nervous System and Senses of Insects 39

CHAPTER VII.
The Reproductive System . • 45

CHAPTER VIII.
Growth and Metamorphosis 48

iv CONTENTS.

PART II.

THE INSECT WORLD.
CHAPTER I.

PAGE

General Classification 52

CHAPTER II.
The Thysanura 55

CHAPTER III.

The Neuroptera and Pseudo-Neuroptera 58

Order Ephemeroptera 59

Order Odonata 60

Order Plecoptera 63

Order Platyptera 6/;

Order Neuroptera 72

CHAPTER IV.
The Orthoptera 79

CHAPTER V.
The Hemiptera, or Bugs 100

CHAPTER VI.
The Coleoptera, or Beetles 164

CHAPTER VII.
The Lepidoptera . 240

CHAPTER VIII.
The Diptera, or Flies 327

CHAPTER IX.
The Hymenoptera 370

CONTENTS. V

PART III.

INSECTICIDES, PREVENTIVES, AND MACHINERY.
CHAPTER I.

PAGE

Predaceous Insects, Parasites, and Fungous Diesases . . . 418

CHAPTER II.
Farm Practice to prevent Insect Attack 423

CHAPTER III.
Preventives 430

CHAPTER IV.
Insecticides 434

CHAPTER V.
I^Iachinlry 454

ACKNOWLEDGMENTS.

The illustrations in this book are derived as follows : Electro-
types were loaned for the purposes of the work by the Agricul-
tural College Experiment Station of New Jersey, of figures Nos.
4, 5, 6, 7, II, 13, 14, 15, 28, 29, 30, 32, 34, 35, 36, 37, 38, 39,
41, 43, 44, 45, 50, 53, 64, 72, 83, 84, 85, 88, 89, 95, 99, 103, 104,
105, 114, 127, 128, 129, 130, 131, 132, 133, 134, 136, 137, 138,
142, 143, 144, 146, 147, 149, 157, 158, 160, 161, 162, 164, 166,
167, 170, 171, 172, 173, 174, 175, 176, 178, 179, 180, 181, 182,
183, 188, 189, 190. 192, 194, 195, 200, 201, 202, 204, 206, 212,
214, 216, 217, 218, 219, 221, 222, 225, 227, 228, 229, 230, 231,
232, 233, 234, 236, 238, 239, 241, 242, 243, 246, 247, 255, 263,
264, 265, 274, 278, 279, 281, 283, 286, 287, 288, 289, 290, 291,
296, 297, 298, 299, 300, 307, 314, 321, 332, 333, 334, 341, 342,
343. 349. 350, 351. 352, 357. 362, 366, 368, 369, 375, 377, 380,
386, 387, 392, 393, 394, 395, 396, 397, 398, 399, 401, 409, 410,
411, 412, 413, 416, 417, 418, 419. 424, 425, 426, 430, 432, 434,
435. 437. 438, 440, 441. 444. 445. 44^, 447- 448, 449, 450, 454,
455. 457. 458, 459, 460, 461, 462, 463, 464, 465, 466, 467, 468,
469. 471, 473, 475, 480, 481, 482.

By the courtesy of the Secretary of Agriculture and of the
Division of Illustrations in the United States Department of Ag-
riculture, electrotypes were obtained for figures Nos. 22, 23, 48,
56, 58, 73. 74. 75. 76, 81, 82, 86, 87, 90, 91, 92, 93, 100, loi,
112, 116, 117, 118, 120, 121, 122, 124, 148, 151, 152, 168, 193,
198, 209, 223, 224, 226, 244, 245, 292, 293, 294, 295, 315, 316,
318, 339, 340, 358, 360, 363, 364, 365, 371, 374, 376, 383, 389,
390, 391. 402, 404, 405, 406, 407, 408, 431, 452, 474, 483.

The J. B. Lippincott Company kindly loaned the following
from Saunders's " Insects Injurious to Fruits" : Nos. 55, 59, 60,
6ia, 65, 79, 80, 94, 97, 98, 102, 109, 125, 159, 165, 169, 191,
197, 199, 203, 211, 213, 220, 240, 254, 259, 270, 271, 275, 276,

vui ACKNOWLEDGMENTS.

^n, 284, 302, 308, 309, 310, 311, 312, 313, 324, 325, 326, 327,
328, 329, 330, 331, 337, 338, 347, 353, 354, 367, 372, 373, 400,
403, 422, 428, 429, 443 ; and from French's " Butterflies of the
Eastern United States," Nos, 253, 260, 261, 262, 268, 269, 273.

From Prof Lawrence Bruner, of the University of Nebraska,
were purchased electrotypes of figures Nos. i, 26, 31, 33, 42, 46,
47, 51, 52, 6ib, 62, 68, 70, 71, 96, 107, no, 115, 139, 140, 141,
156, 163, 186, 256, 319, 320, 335, 336, 355, 421, 433.

From Houghton, Mifflin & Co., pubhshers of the " Riverside
Natural History," were purchased Nos. 12, 17, 77, 78, 106, 177,
378, 414, 423, 451, 472.

From the Entomological Society of Ontario electrotypes were
obtained for figures Nos. 207, 208, 258, 420, 456.

From the Cornell Experiment Station, through the kindness
of Mr. M. V. Slingerland, electrotypes were secured of figures
Nos. 40, 119, 145.

Mr. G. C. Davis, of the Agricultural Experiment Station of
Michigan, furnished stereotypes of figures Nos. 196, 235, 301,
370, 388, 439.

Prof Herbert Osborn, of the Iowa Agricultural College, kindly
loaned for reproduction figures Nos. 108, 356, 382.

Dr. Otto Lugger, State Entomologist of Minnesota, supplied
electrotypes of figures Nos. 280, 427, 442.

Dr. F. H. Snow, of Lawrence, Kansas, loaned for reproduc-
tion figures Nos. 123, 210.

Mr. F. M. Webster, of the Ohio Experiment Station, per-
mitted the reproduction of figures Nos. 205, 237.

Mr. A. D. Hopkins, of the West Virginia Experiment Station,
granted the same favor for figures Nos. 384 and 385.

Dr. A. S. Packard kindly supplied electrotypes of figures Nos.
16 and 470.

To Dr. G. Brown Goode, Director of the United States Na-
tional Museum, I owe electrotypes of figures Nos. 27 and 381.

From Mrs. C. V. Riley were purchased electrotypes of figures
Nos. Ill and 361.

Dr. J. A. Lintner, State Entomologist of New York, kindly
supplied an electrotype of figure No. 282.

Prof S. A. Forbes was equally courteous concerning figure
No. 187.

ACKNOWLEDGMEXTS. ix

Prof. C. P. Gillette loaned for reproduction figure No. 150.

Mr. Frank Sempers, of Philadelphia, kindly gave figure No.
49.

Mr. H. G. Hubbard, of Washington, obligingly loaned figure
No. 359.

Of the machinery illustrated, an electrotype of No. 476 was
supplied by Mr. McGowen, of 478 by Mr. William Stahl, and
of 479 by W. & B. Douglas.

The following are originals, and were especially prepared for
this work : Nos. 2, 3, 8, 9, 18, 19, 20, 21, 24, 25, 54, 57, 63,
66, 67, 69, 113, 126, 135, 153, 154, 155, 184, 185, 215, 248, 249,
250, 251, 252, 257, 266, 267, 272, 285, 304, 305, 306, 322, 323,
344, 345, 346, 348, 379, 415, 436, 453, 477. Of these original
figures, some are photographs, others are from drawings by the
author, some are redrawn, and a few are duplications of published
figures where no plates were known to be in existence.

To all who have in any way aided in the preparation of this
work, and especially to Mr. L. O. Howard, of Washington, who
kindly read my chapter on Hymenoptera, and Prof. Lawrence
Bruner, who kindly read my chapter on Orthoptera, I tender
my sincere thanks.

INTRODUCTORY.

Insect injurj' to agricultural products amounts each year to
millions of dollars, and, as a whole, shows a tendency to increase
rather than otherwise. It is not only the actual devouring of
plant tissue that causes loss ; the effect upon the product may
be to reduce its grade, or make it more or less unsalable and
unprofitable. In the competition for markets, the grower of
the best will always have an advantage ; first-class fruits and
vegetables rarely fail to bring some profit, where low-grade
products cannot be sold at any price ; and no fruit that is
wormy, defaced, or otherwise injured by insects ever ranks as
first-class.

Progressive farmers have long been aware of this, and the
science of economic entomology has grown up in response to
their demands for information concerning insect depredation and
for means of protection against it. It is a science far from sys-
tematized as yet ; made up of fragments published here, there,
and everywhere, rarely complete in themselves and often con-
tradictory as to the remedial measures suggested. There have
been efforts, more or less successful, to compile books of infor-
mation concerning the insects attacking certain crops or kinds
of crops ; but there is not now in existence any work which
gives the agriculturist and student of economic entomology that
basic knowledge that enables him to recognize the nature of the
insect he finds causing injury, or makes it possible to decide
what sort of remedies should be applied. In other words, the
underlying facts upon which the scientific application of remedial
or preventive measures is based are not accessible to the very
class that most needs them.

In this book an attempt is made to present these matters com-
pletely enough to give a foundation upon which further informa-
tion may be added ; for whatever changes may occur in our

xii INTRODUCTORY.

battery of insecticides, the philosophy of their application will
remain the same. To do this it is necessary to give an outline
of the characteristics of insects generally ; of those features that
distinguish them from all other animals, and of those peculiarities
upon which we must base our hope of conquering them. Enough
of the structure is described to show how they are built up, and
all the different orders are referred to, so that the intelligent
reader may recognize at least the group to which a specimen
belongs and may be able to determine whether or not an injurious
species is in hand. The direct needs of the agriculturist have
been kept constantly in mind ; but the effort has been to give
also a general information on the subject of insect life, and the
work should be useful to students in all save advanced college
courses, where technical or systematic studies outrank all others.

AN ECONOMIC ENTOMOLOGY.

PART I.
STRUCTURE AND CLASSIFICATION.

CHAPTER I.

THE GENERAL STRUCTURE OF INSECTS.

Insects are animals made up of a series of rings or segments
stiffened by a hard substance called chitine, and connected by a
membrane which allows of more or less freedom of motion be-
tween them in one or more directions. In this they agree with
the worms, differing from them, however, in the adult stage, in
that the segments are grouped into three regions ; the head,
thorax, and abdomen, as shown in the diagrammatic sketch of
the grasshopper. In the larval stage of many insects these re-
gions are not well marked, and they resemble worms decidedly,
but nearly always have a distinct head and more or less distinct
legs. If neither head nor legs are visible, the larvae are chunky
and maggot-like or grub-like, rarely long and cylindrical. In
fact, we have very few terrestrial worms in our country, and
most of the so-called ' ' worms ' ' are really insect larvae.

As a rule, an insect is made up of thirteen rings, counting the
head, and in the larval stage they are usually easy to make out,
especially in caterpillars, which may be abundantly secured at any
time during the summer. In the adult they are often more or
less obscure. Following the head we have three segments which
form the thorax or trunk, and these bear all the organs of loco-
motion in the adult. In the larva, when organs of locomotion
are present, one pair of legs is found on each of these segments.

12 AN ECONOMIC ENTOMOLOGY.

Nine rings are assigned to the abdomen, though some of them
may be modified into structures faciHtating egg-laying or other
special purposes. In the adult no appendages of any kind, ex-
cept ovipositors, anal filaments, or cerci, are found ; but in the
larva, where there is often no real separation between thorax and
abdomen, the latter may bear organs of locomotion which differ
in their general appearance and structure from the true legs, and
are therefore called "false feet," or pro-legs. The number of
these pro-legs sometimes enables us to recognize the order to
which a larva belongs, where it otherwise closely resembles
another. For instance, all the true caterpillars are larvae of
Lcpidoptera, or butterflies and moths, and these never have
more than four pairs of pro-legs at the middle of the body and
one pair on the last segment, making, with the true legs, eight
pairs in all. In the larvae of the sawflies, a family of the Hymen-
optera in which the resemblance to caterpillars is very close, there
are at least five pairs of pro-legs at the middle and one pair at
the end of the body, or no less than nine pairs of legs instead
of eight as before.

No insect has more than two pairs of wings, and these are
attached to the second and third thoracic segment. Some have
only a single pair, as in the true flies, and then they are on the
second or intermediate segment. The prothorax, or first seg-
ment, never bears wings. Each thoracic segment bears a pair of
legs, which are themselves divided into joints or segments, and
their structure will be described more in detail later on.

This division into three distinct regions and the limitation to
six legs in the adult separate the insects from crustaceans, like
lobsters, crabs, shrimps, and the like, and from the spiders ; none
of which have the head separate from the thorax, while all have
eight legs instead of six. An insect in the adult stage is there-
fore a jointed animal, the rings, thirteen in number, separated
into a head of one, a thorax of three, and an abdomen of nine
segments ; moving by means of three pairs of jointed legs. Some
differences between ' ' larva' ' and ' ' adult' ' have been spoken of,
and it has been indicated thereby that at different periods of
their lives insects are unlike in appearance. This branch of the
subject is exceedingly interesting, and will be treated more fully
in Chapter VIII. It is only necessary to say here that, in speak-

STRUCTURE AND CLASSIFICATION.

14 AN ECONOMIC ENTOMOLOGY.

ing of the difference between larva and adult, reference is particu-
larly made to those forms in which the two stages are totally
unlike each other in appearance. Some of them resemble each
other throughout their entire life, and here the term ' ' nymph ' '
is often employed instead of larva.

It remains to say a few words concerning the chitine, which
forms so large a part of the outer skeleton or crust. This sub-
stance is found in insects and in certain of
■ ■ the crustaceans, and is a flaky, horny, or

shell-like material which may become very
hard, and is impenetrable to most liquids
not absolutely corrosive in character. The
Section through insect importance of this fact it is necessary to

crust, showing layers of . . , . ^ . ...

chitine at c, the cellular recognize in our Selection of insecticides,
layer or hypodermis at bccausc nothing that wc Can apply with any

h, and basal membrane r ^ ^ ^-l i ^ • re • ^i

^j ^ saiety to the plant is sumciently active to eat

through or penetrate the outer skin into the
insect body except under peculiarly favorable circumstances.
None of the oils penetrate it readily, even gasoline, benzine, or
kerosene being resisted. Alcohol, chloroform, and ether are also
unable to make their way through any but a very thin coating.

CHAPTER II.

THE HEAD AND ITS APPENDAGES.

The head of an insect bears structures of great interest from
the economic stand-point, and of these the mouth parts are the
most important. In most cases a glance at the structure of the
mouth gives a clue to the food habits of the species, and may
convict a culprit whose work has been discovered, or determine
the character of the remedy to be applied.

Roughly speaking, two types of mouth structure are found in
insects, — the biting or mandibulate, and the sucking or haustel-
late ; though there are modifications of both which are somewhat
intermediate in character.

In the typical "mandibulate" or biting mouth, the mandibles

STKi'CTL'KE A. YD Cl.ASSIFICATIOX.

15

Fig. 7v

or upper jaws are distinct and prominent. They work horizon-
tally, from side to side, instead of vertically, or up and down, as is
the case in the higher animals, and their form and general shape
often furnish an indication to the character of the species, — that is,
whether it is predace-
ous, living upon ani-
mal food, or whether
it is phytophagous,
feeding upon plant
tissue. This alone, in
some orders, suffices
to tell us whether we
have to deal with a
friend or an enemy.
If the jaws are rather
long, sharp-pointed,
with slender, sharp
teeth on the inner side
(Fig. 3, c, d), it may
be safely classed as
predaceous ; if they
are broad, stout, con-
cave within, the edges
meeting broadly, even
if toothed, or if they
are gouge-shaped
(Fig. 3, a, e), we can
say with great confi-
dence that the species feed upon vegetable tissue. Of course
some uncertainty may result in intermediate types (Fig. 3, b) ;
but the rule holds good generally, and where it leaves a doubt,
some other character will readily determine the question.

Forming the front of the mouth and covering the base of the
mandibles is the upper lip, or labrum ; on the inner side of which
there is usually a sensitive structure, the epipharyyix, which con-
tains the organs of taste, and corresponds as nearly as may be to
the palate in higher animals. It has no special function in feed-
ing, and often seems to form part of the front of the head itself

Below the mandibles we have a second pair of jaws or fuaxillce,

Mouth parts of a mandibulate insect : different types
of mandibles at a,b, c, d,e ; /, the labrum-epipharynx ;
g, h, types of maxillae ; the cardo at c ; stipes, st ; sub-
galea.j^,- galea as marked ; palpus bearer, ;>/V,- palpus
at mxp ; lacinia at lac ; and digitus at dig- ; i, the labium
with sub-mentum, sm, mentum, m, ligula, lig, para-
glossa,/a>-, and palpi.

I

1 6 ^A" ECONOMIC ENTOMOLOGY.

much more complicated in structure, and made up of a number
of more or less well-marked smaller pieces, which vary consider-
ably in form and shape according to the food habits of the insect.
Attached to each maxilla is a palpus, or feeler, which often bears
organs of special sense, and is probably used by the insect to
recognize the character of its food. In function this maxilla is
auxiliary to the mandibles, which cut and tear the food, and de-
liver it in coarse shape to the maxillae. These assort and break
it up yet more to better its mechanical condition, and deliver it
to the labium, or lower lip, which also takes part in mixing the
food. There are great differences in this maxillary structure,
corresponding to the food habits ; and there may be teeth,
brushes, or other appendages suited to the requirements of the
insect. It is rarely necessary to study these in detail, and Fig. 3
illustrates sufficiently a typical form, with all the parts named.

The labium, or lower lip, closes the mouth opening beneath,
forming its floor, on which is another sensitive surface, the hypo-
pharytix, which may be compared in function to the tongue of
the higher animals. As a rule, this labium is much less complex
than the maxilla, and it may be only a single piece or plate,
though, like the maxilla, furnished with a pair of palpi or feelers.
A typical labium is shown at Fig. 3, and the names of the parts
are given. Close study shows that originally the labium was
made up of just as many parts as the maxilla, but they have
grown together, in the course of time, for the more complete
closure of the mouth opening.

Insects with the mouth as above described, no matter what
their feeding habits, are always susceptible of being poisoned
through their food ; that is, they may be reached by means
of stomach poisons. Sometimes, of course, they feed in such
positions that we cannot apply the poison satisfactorily, — e.g.,
inside of plant tissue ; but this does not alter their susceptibility ;
it simply means that we cannot take advantage of it.

Of the hatistellate or sucking mouth there are several varieties,
functionally quite diverse and indicating difference in habit.

Butterflies and moths differ from all other insects in having the
mouth formed into a flexible tube, coiled like a watch-spring
under the head and between the labial palpi, which are the only
visible mouth appendages present. The mandibles have disap-

STRUCll.'RE AXD CLASSIFICATION.

17

peared entirely, and all the other structures have been so modi-
fied that nothing remains except this flexible sucking tube. I
use the term "tube," although it is not such in reality, being
made up of two hollow crescents, more or less firmly held to-
gether, so that, practically, it serves all the purposes of a complete
tube. When the insect feeds the tongue is extended, the muscu-
lar structure being accommodated in the walls of each half of the
tube. Fig. 4 illustrates a section through a butterfly tongue,
showing the way in

which the two parts '^' 4-

are united. At its
tip there are often
more or less devel-
oped processes which
serve as taste cups,
and also to assist in
gathering up the
minute globules of

nectar. Section through a butterfly tongue.

A tongue of this
description indicates a type which can never be harmful to vege-
tation, because it is not fitted for either piercing or eating plant
tissue ; but it is, on the contrary, of direct use in pollenizing
flowers. Butterflies and moths are never injurious in the adult
stage, however much their larvae may offend ; but many are
especially adapted for pollenizing certain flowers. Thus the
" Hawk-moths," with tongues five and six inches in length, are
able to reach to the very base of flowers like the petunias, even-
ing primrose, "Jimpson weed," and many orchids.

A widely different type of sucking mouth is found among the
"bugs," or Hetniptera. Here, instead of a flexible tube, there
is a jointed, rigid beak or rostrum, made up of either three or
lour segments, inside of which run four pointed lancets. This
beak is not a complete tube, but narrowly open in front and at
the tip, to permit the protrusion of the lancets. Insects with this
structure gain their food by piercing the plant tissue and sucking
the juices, and such a structure always leaves its possessor open
to the suspicion of being injurious. As a matter of fact, many of
the Hemiptera are really predaceous upon other insects ; but, as

yiA' ECONOMIC ENTOMOLOGY.

a rule, they will bear close watching. One thing is certain, how-
ever : no insect with this type of mouth structure can be reached
by means of a stomach poison. Destruction through its food is,

therefore, absolutely impossi-
ble, because we cannot poison
the plant juices by any method
thus far at our command. An
insect of this kind is incapable
of eating any solid food what-
ever, and no matter how thor-
oughly covered with a corro-
sive poison the outside of our
plants may be, it would get
none, since it only punctures
the tissue without absorbing
any portion of the outer sur-
face. Thus the determination
of the type of mouth structure
often limits or decides the char-
acter of the remedy to be used
in destroying the insect.

Among the Diptera, or flies,
we have a number of interest-
the ing modifications of the suck-
ing mouth. One series is fur-
nished with lancets similar to
those in the bugs, but more numerous, representing different
mouth structures, and not always carried into the head itself.
The sucking structure is also quite different, and never forms a
rigid, jointed beak. Mosquitoes and horse-flies are examples of
this kind ; but gradually the lancets disappear, and in most of the
flies only the sucking lip, often greatly and interestingly developed,
remains. The common house-flies and blow-flies are types of this
modified form, and are capable of taking liquid food only, though
often seen attacking solids. If the mouth of a fly be examined
under the microscope, there will be seen at the tip of the lip a
series of deep grooves, stiffened with chitinous loops, and armed
with sharp projecting edges. When the fly wishes to feed on a
solid, it scrapes the surface by means of these rasp-like projec-

Mouth parts of a plant-louse
jointed beak ; b, the lancets, much enlarged
c and d illustrate the feeler and foot.

STRUCTURE AND CLASSIFICATION.

19

lions, securing a small amount of fine shreds and scraps. These it
moistens with a drop of saliva, which has great solvent properties,
and then draws up the mixture by means of a sucking or pump-
ing stomach. Licjuids are taken in the same way, and the insects
may be said to lap as well as suck their food. Flies as adults are
not injurious to vegeta-
tion, whatever may be Fig. 6.
said of their larvie ; but
some of those fitted for
piercing, like the mos-
quitoes, horse-flies, and
gnats, are often trouble-
some or injurious to
stock, and occasionally
render regions infested
by them scarcely habit-
able for man.

The bees seem to
combine the features of „. . .... <■ ..u « .. .v.

Piercing; mouth structures of a horse-fly : the
a biting and sucking sucking lip is omitted. Much enlarged.

mouth ; the mandibles

being fully developed and the labium greatly elongated, that they
may gather the nectar upon which they feed and which they
store, even from the deepest flowers. This modification will be
more fully described in speaking of the bees themselves.

All the types of mouth structures above described and figured
are derived from one original form by gradual modifications of
the different pieces ; but this can be traced only in a long series
of preparations from many different families and species.

Next to the mouth parts, the most important appendages of
the head are the antennae or feelers. These are variable in form,
and in certain orders their structure indicates, unfaiHngly, the
food habits of the insect. They are made up of a variable num-
ber of joints, differing greatly in their proportion to each other,
in their shape, and in their functions. Ordinarily the antennae
are intended as tactile organs, — that is, for touching, as the com-
mon name "feeler" indicates ; but it is very certain that other
sensory structures are also located there. The perception of
odors, or the sense of smell, is a very important function, and

AN ECONOMIC ENTOMOLOGY.

more than likely there is also a sense of hearing connected with
them. In some of the nocturnal moths they are broadly feath-
ered or pectinated, much more prominently in the male than in
the female. It is believed that the reason for this is that the
insects are compelled to find their mates entirely by the sense of

Fig. 7.

Tip of the mouth of a lapping fly, showing the pseudo-trachea on the inner face of the
lips. Much enlarged.

smell. That it is not food they seek is proved by the fact that
where these feelers are most developed the mouth parts are often
entirely aborted and the insect takes no food at all. Certain
"carrion beetles," also nocturnal in habit, are attracted for long
distances to their food, and, even where purposely hidden, they
find it without difficulty ; proving that the sense of smell alone is
used. It may be convenient to consider here a few of the com-

STRUCTC'RF. AND CLASSIFICATION. 21

mon types of antennal structure, which occur in all insects, that
they may be referred to hereafter without especial description.

The antennae are said to h& filiform, or thread-like, when the
joints are nearly even throughout, cylindrical, tolerably equal in
length, and similar in general appearance. A serrate or saw-
toothed antenna has the joints more or less triangular in shape
and so fitted that one margin resembles the toothed edge of a
saw. Quite frequently antennae of this type are distinctly flat-
tened. From such a serrated form we pass gradually into the

Fig. 8.

Antennal types. — a, filiform and pubescent; b, serrate; c, singly pectinate; d, bipecti-
nate; e, clavate ; y, capitate; g, geniculate; h, lamellate.

pectinated or comb-toothed type, where the joints are furnished
laterally with processes of variable length. When both sides of
the joints have these processes the antenna is said to be bipec-
tinated or feathered ; when the processes become very slender,
almost hair-like, and exceedingly numerous, it is said to be
plumose. A feeler is clubbed, or clavate, when the joints toward
or at the tip suddenly or gradually enlarge to form a more or
less evident club or bulb, and this type is widely distributed in
all the orders, a variety of terms being in use to indicate the
particular form of the club. A lamellate feeler has at its tip a
series of elongate, flattened or leaf-like joints, usually applied
close together to form a solid mass that conceals and protects

y4A^ ECONOMIC ENTOMOLOGY.

the delicate sensory structure on the inner surface. An antenna
is vioniliform, or bead-like, when the joints are more or less
spherical and set together in such a way as to resemble a series
of beads on a string.

As a rule, the antennae are straight, without break from base
to tip ; but occasionally they are geniculate, or elbowed ; tliat is to

say, there is one very long
basal joint, the "scape," fol-
lowed by a series of smaller

Fig. io.

Fig. 9.

_ ,, ^ , Head of wasp, to show regions: a,

'^' iT ■o^O'^ 'C^ compound eyes ; b, clypeus ; c, la-

Antennal types: a, moniliform ; 6, joints ciliated; brum; rf, mandibles; 6", ocelli ; /.place

c, bristle-tufted; d, plumose; e, setaceous. where antennae are inserted.

segments set in at right angles to it. Usually an elbowed an-
tenna is also clubbed at the tip, and so we divide the structure
into "a scape" at the base, the "club" at the tip, and the
" funicle" embracing the intervening portion.

The feelers may be clothed with fine, soft, more or less dense
hair, and are then pubescent ; or furnished with lateral hairs of
moderate length set in regularly, and are then ciliated or fringed ;
or they may have single or bunches of stiff bristly hair, and are
then said to be bristled, or bristle tufted.

These are all the movable appendages of the head, and there
remain only the organs of sight, which are perhaps better con-
sidered under the heading of sense organs. It is only necessary
to say here that the compound eyes are often very prominently
developed, and that they are usually set at the sides, often form-
ing the greater portion of the head itself. The ocelli, on the
other hand, are always very small structures ; in the adults, never
more than three in number, and quite variably arranged.

STRUCTURE AND CLASSIFICATION. 23

CHAPTER III.

THORAX AND ABDOMEN.

The thorax, or middle region of the body, is, as has been
already stated, composed of three rings, termed in their order
the pro-, meso-, and metathorax ; meaning fore, middle, and
hind thorax. These rings vary greatly in their proportion to
each other : it is rare that they are equally well developed, and
whenever this is the case it indicates a low type of insect, — that
is to say, one very little specialized. Usually they are grown
together to some extent, and this tendency continues until we
find in the flies and bees the entire thoracic region apparently
composed of one solid mass, — the rings being not at all movable
upon each other. Insects of this type are highest in the scale
and the most specialized. In other orders, notably the Coleop-
tera, or beetles, the prothorax only is free and well developed,
the two other rings being united together and not movable one
upon the other. This forms a sort of intermediate type, and the
rank of insects is determined, to some extent, by the development
of this region of the body.

If the thorax of a grasshopper, a beetle, or a wasp be rather
closely examined, it will be found that it is made up of a large
number of little pieces, divided by impressed lines, and sometimes
these pieces are movable one upon the other. They are called
sclerites, and a sclerite, whenever that term is used, always
means a solid piece bounded by impressed lines, or sutures, as
they are termed. Perhaps ' ' seams ' ' better represents the actual
case than "lines," because they mark the places where pieces
have been joined together, even if the joint be now a solid one.
Though these pieces seem confused at first sight, yet there is a
distinct plan in their arrangement, and, while it is not necessary
to go much into detail, it is well to know at least the regions
of the segments and the terms applied to them. In Fig. 11
will be found an illustration of the under side of a beetle, in
which all the sclerites of that part of the body are named. Those
who wish a more accurate knowledge can compare a series of

-'4

AN ECONOMIC ENTOMOLOGY.
Fig. II.

maxinaru

/T7 ^"^'1
puzbtcs . 7

"^ Tv mqxdi

A beetle, Harpalus caliginosus, from the under side, with all the pieces named.

STKl'CTURE AND CLASSIFICATION. 25

insects with this tigure, and by identifying the different pieces
observe for themelves what modifications have taken place. The
upper side is always called the dorsum, or dorsal surface, while
the under side, between the legs, is the sternum, or breast.
Laterally, between the sternum and the dorsum we find the
pleurum, whicli is a region rarely referred to in general descrip-
tion. The "dorsum," " dorsal surface," and "sternum," on the
other hand, are terms of frequent occurrence in the literature of
economic entomology, and it is well to know exactly what is
meant by them.

As has been previously said, all the organs of locomotion in
the adult insect are attached to the thoracic segments ; never
more than three pairs of legs, one pair to each segment, and
usually two pairs of wings, borne on the meso- and metathorax.
The prothorax never bears wings, and, when only a single pair
is present, as occurs normally in the flies, or Diptera, this is on
the meso- or middle thoracic segment.

Of the wings, or organs of flight, all that need be said here
is, that they are more or less membranous, flattened, and stiff-
ened by "veins" or chitinous rods. They vary greatly in char-
acter, and must be especially described for each order, their
general structure being all that it is necessary to give here. In
their origin wings are merely collapsed sacs, — that is, each is a
bladder-like outgrowth from the body wall, that assumes definite
form, but remains filled with liquid until ready to assume its final
shape. Then it is gradually distended to full size, the liquid is
absorbed, and the walls of the bladder unite and become so
closely welded together that it is impossible afterward to separate
them. The wing seems like a single thin membrane, or horny
shell, as the case may be, and the veins appear like hollow rods
or cylinders, though originally they were mere thickened grooves
on opposite sides of the distended bladder. The arrangement of
the veins, or " venation," is of very great importance in classifi-
cation, but needs no particular exposition here.

The legs, always six in number in the adult, are jointed, or
made up of a definite number of parts or pieces. They are fixed
into the thorax at the sides of the sternum, or between the breast
and the sides, and are fitted into a body cavity by means of a
ball-and-socket joint, giving a great range of motion. The ball

26 AN ECONOMIC ENTOMOLOGY.

portion belongs to the leg and is called a " coxa," and the socket
is the " coxal cavity." Attached to the coxa is the "femur,"
or thigh, usually the stoutest part of the leg, and corresponding
to the same portion of the leg in the higher animals, most of the
muscular system being found in it. It is often strengthened at
the base by a small supplementary piece called the ' ' trochan-
ter," which sometimes forms an intermediate segment between
coxa and femur, and may be even two-jointed, as in the parasitic
Hymenoptera. At the end of the femur is attached the " tibia,"
or shank, which varies greatly in structure according to the
habits of the insect, being modified for digging, tearing, swim-
ming, clasping, or other special functions. It is armed in many
ways, and becomes an index to the life history of the insect,
furnishing, also, many good characters of use in classification.
Economically, it is useful in that it is a guide from which we can
often get an idea of the kind of existence that the insect leads, —
whether it is a digger, a swimmer, or a carnivorous type. The
terminal part of the leg is the " tarsus," or foot, and this is also
jointed, — five joints being usual, though variations frequently
occur. The last joint is armed with a pair of claws, and between
them we may have "pulvilli," or small pad-like structures, by
means of which flies and other insects cling to smooth surfaces
and are able to walk back downward on ceilings. The differ-
ences in the leg structure are easily seen with a little experience,
and In some orders, notably the Coleoptera, they serve to divide
the insects into large groups or series.

The abdomen normally contains nine segments, but these are
rarely all distinct. As a rule, one or more are modified to form
sexual organs or appendages, or shields, or other accessory
structures. It sometimes happens that the segments on the
dorsal, or upper, and ventral, or under, side do not correspond,
one part of the ring being lost or modified. In the adult the ab-
domen never bears organs of locomotion, and, as a rule, no appen-
dages of any kind, except an ovipositor in the female of certain
groups, or a pair of claspers in the male. In some of the lower
orders it bears jointed filaments or appendages resembling feelers,
and these are called " cerci." Only in the lowest of all types do
we find traces of rudimentary legs on the abdominal segments,
indicating a relationship between the insects and myriapods.

STRUCTURE AND CLASSIFICATION.

71

CHAPTER IV.

MUSCLES, DIGESTION, AND CIRCULATION.

Insects have no internal skeleton or bony structure, the body
wall serving for the attachment of muscles and to protect the
inner organs.

Cutting transversely through the thorax of an insect at its mid-
dle, we find the greatest portion of the body cavity occupied by
muscles, which are arranged in bundles attached to the entire
inner surface of the body wall, proceeding to all the appendages,
and thus providing the power that moves the animal. Centrally,
the alimentary canal occupies a part of the body cavity, its size

Fig. 12.

Ideal section through an insect.— a, alimentary canal; h, heart; n, nerve-cord; s, stig-
mata ; t, tracheal tubes ; /, legs ; w, wings.

depending considerably upon the kind of insect in hand. Just
below the dorsal surface is a small tubular structure, at once the
heart and only blood-vessel, while just above the ventral surface
is a white, knotted cord,— the nervous system. Laterally, there
is an opening on each side, from which a ringed tube leads into
the body, dividing and subdividing almost immediately into
innumerable branches, and this is the respiratory or breathing
system. Frequently we find around the alimentary canal a con-
siderable fatty mass, while everywhere through the insect body

28 AN ECONOMIC ENTOMOLOGY.

we meet with a whitish or sHghtly greenish Hquid, much more
abundant in the larva than in the adult ; and this is the blood.
These various systems are of economic importance, for upon
our full understanding of some of them depends the success with
which we can apply insecticides of a certain character.

Perhaps the least important in this view is the muscular sys-
tem. It has been stated that the muscles are found in the form
of bands, which extend from the body walls to the various ap-
pendages, and, of course, they are numerous and strong in pro-
portion to the power required. Thus, for a leaping insect the
muscles moving the legs are very much more developed than
they are in an insect which simply walks or runs, and in a run-
ning insect they are better developed than in one that simply
walks or moves slowly. Where powerful appendages must be
moved, as for instance the mandibles or jaws, several bundles
of muscles frequently converge to a chitinous point or tendon,
which in turn is attached to the appendage, and thus a great
amount of force is exerted at one point, the muscular attach-
ments on the body wall covering a considerable surface and con-
verging all their effectiveness upon one lever only. It is this
arrangement that gives some insects the gnawing power to bur-
row in the hardest woods, and to cut through foreign substances,
like lead, in order to escape from captivity.

Under the microscope it is found that the ultimate structure of
insect muscle does not differ in essentials from that of the higher
animals ; that is to say, it is made up of narrow fibres divided
into cells, and transversely striated. The voluntary muscles of
insects are, therefore, practically like the voluntary muscles of
the higher animals or of men.

The digestive system is of much more importance from the
economic stand-point. On a previous page it has been shown
that two general types of feeding habits exist, the chewing and
the sucking, and the digestive system changes somewhat as the
needs of the organism vary. The mandibulate type, in which
the insect chews its food and subsists upon more or less solid
material, will be first considered. Most insects in the larval stage,
and sometimes also as adults, are voracious feeders, seeming
determined to devour as much as they can possibly contain, in
the shortest possible time ; and the food is in such cases rather

Fig. t,^.

Mandible of a carpenter-bee, with bundles of muscular fibres attached, each bundle
converging to a tendon, and the latter attached to a mandibular procesb.

STRUCTURE AND CLASSIFICATION. 29

Fig. 14.

Digestive systems : of a katydid, at a; of a grasshopper, at b ; and of a roach, at c. All
the parts are named save the thread-like Malpighian tubules.

30

AN ECONOMIC ENTOMOLOGY.

coarsely ground up by the mouth parts, and forced through the
gullet or oesophagus into the crop. The oesophagus is simply a
slender tube, usually straight or only a little bent, at the mouth
of which salivary glands open, and the food, mixed with saliva,
passes through it into the crop. This crop is a more or less
muscular, but always distensible sac, and usually the largest
single organ in the body. It is used, primarily, as a place to
store food when the insect has the opportunity of obtaining it,
and is capable of containing a comparatively enormous amount
of material. At its posterior end it opens into a gizzard, or
grinding stomach, and this receives the food in small quantities,
to be further reduced and put into better mechanical condition
for assimilation. For this purpose it is armed with a complicated
set of plates and teeth, not alike in any two species, while its
muscular coatings are dense and powerful, giving great twisting
and grinding force. Sometimes the gizzard is well developed
and prominent ; but often it is greatly reduced, appearing as
little more than a slight specialization of the end of the crop.
Its development depends very largely upon the character of the
food and the feeding habits. Insects that eat indiscriminately all
sorts of material, like roaches and crickets, have it best developed.
From this gizzard the food, now in excellent mechanical con-
dition, passes into the true stomach, ox ckylific ventricle, receiving
at its mouth the secretions of the ccecal tubes or pouches. This
secretion is digestive in character, like a similar liquid in higher
animals, and assimilation begins in this part of the system. The
stomach varies greatly in length in the different kinds of insects,
and as much in relative size and the strength of its muscular
coating. At its posterior end we find the long and slender Mal-
pighian tubules, which often envelop the whole system in a ver-
itable net-work of fine, thread-like masses. These structures are
supposed to represent kidneys and to have a similar excretory
function. They open at the junction of the stomach with the
iletiin,ox small intestine, and in this the assimilation or absorption
of food products is completed, the remnant being forced into the
large intestine, or colon, where it is prepared for excretion through
the rectiim. A pair of glands near the end of the rectum secretes
a mucus, probably intended as a lubricant only.

The salivary glands vary in number, and one or more may be

STKC'CrUKE AND CLASSIFICATION.

31

Fig. 15.

modified for special purposes ; as in some of the piercing insects
like bugs or the mosquitoes, where an irritant poison is secreted,
or in certain beetles, where the saliva has
both a staining and a burning effect upon
the skin, or in many larvae, where the se-
cretion forms a silk when hardened by ex-
posure to the air. The anal glands may
be similarly modified, but much more
rarely than those at the anterior end of the
body. In the "Bombardier beetle" their
secretion volatilizes suddenly when expelled
into the air, and forms a blue smoke, like
the discharge from a small cannon. In
Hymenoptera, including bees and wasps,
the secretion is poisonous, and accessory
to the functions of the sting. More rarely
a silk is produced from these glands. Taken
altogether, the digestive system varies
greatly in length, being .sometimes a
straight tube only, the various portions
very incompletely divided off. In other
cases it is quite complex, coiled upon
itself, the parts well defined, and the sys-
tem as a whole two or three times the
length of the entire insect, different kinds
of structure being found in the various
parts. The figures given herewith illustrate
some of these differences.

In the sucking or haustellate type the
essential structure of the alimentary canal
and the differentiation of the parts are much
the same. There is, however, a great reduction in the size of the
gizzard, which is very often entirely wanting. If present, the
armature is reduced to a mere ridging, or a slight, irregular
thickening of the walls of the posterior end of the crop. In the
Lepidoptera there is often a peculiar accessory pouch, which
seems to serve the purpose of a storage reservoir, or secondary
crop, and this is attached by a narrow neck to the opening of the
true crop. In the bees the crop is unusually elastic, and capable

Salivary gland of the cat-
erpillar of Melittia ceto,
modified for silk spinning:
mandible of the same,
above.

32

AN ECONOMIC ENTOMOLOG\.

of enormous distention compared with the size of the insect, and
this is to accommodate the honey collected by the insects to be
carried into the hive.

In the use of poisons acting through the stomach, the arsenic,
which is usually employed, is taken in with the food and gener-
ally carried into the chylific ventricle before it becomes effective.
In the crop the food is generally too dry to cause the necessary
solution of the caustic properties of the arsenic, which is neces-
sarily applied in its least soluble form ; but by the time it has
passed through the gizzard and has reached the stomach, becom-
ing moistened and mixed with the secretions that have been
already mentioned, it becomes active. Some insects are able to
take a very large quantity of poisonous material without injury ;
succumbing only after two or three days to the effects of a poi-
sonous meal. It is probable that in such cases the digestive
liquids exercise a less solvent effect upon the toxic mixture.

Ordinarily, digestion in insects is exceedingly rapid. Among
caterpillars, for instance, feeding is often almost continuous, and
twenty-four hours are sufficient to pass through the entire diges-
tive system food two or three times the weight of the larvae
themselves.

Fig. i6.

Heart of a stag-beetle, showing the wings and chambers : at the side, the interior of a
chamber, to show the valves.

Insects have no system of arteries and veins, and only one real
blood-vessel, which serves also as the heart. This, as has been

S7'A'CV7('A'/-: AND CLASSIFICATION.

33

indicated, lies just under the back, and in a cavity formed by a
series of peculiar triangular muscles known as the ' ' wings of the
heart;" and these serve to prevent undue pressure upon it.
The organ is simply a long tube, open at both ends, and divided
into a variable number of chambers, into which the blood is
admitted at the sides, at intervals along its length. The heart-
beat consists of a wave of contraction beginning at the posterior
end, forcing the blood forward and out into the head. Some-
times one wave is completed before another one starts, and
sometimes two or even three waves may be on the road at one
time. Sometimes the beat is exceedingly sluggish, and some-
times, in active insects, it is very rapid. After the blood has
been forced out of the heart it first bathes the head parts, and
then makes its way between the muscles and other organs through
the body cavity and into the appendages. Part of it bathes the
alimentary canal, where it receives the products of digestion, and
these are carried everywhere and assimilated by the various
tissues, the blood eventually finding its way back to the heart,
to begin its journey anew. The fact that there is no closed
system of blood circulation is peculiar, and in this insects differ
from all the higher animals. It necessitates a very decided
modification of the respiratory or breathing system, and this
forms the subject of the next chapter.

CHAPTER V.

THE RESPIRATORY SYSTEM.

The respiratory or breathing system of insects is adapted to
the system of blood circulation. It is important from the eco-
nomic, as well as interesting from the scientific, stand-point, for
upon this rests the basis for the application of contact insecticides.

Insects have no lungs, and nothing which at all corresponds to
them. They have no means of taking in air at the head or
through the mouth ; but breathe from the sides, where there is a
series of breathing-pores, or spiracles, through which the air is
taken into the body cavity. Typically, one pair of spiracles

3

34

AN ECONOMIC ENTOMOLOGY.

occurs on each body segment ; but as a matter of fact some of
the segments, especially in the adult, lose them, the insect de-
pending upon a more limited number as the main trunks become
enlarged. The insect blood requires oxygen, as in the higher
animals, and, as there -are no lungs to which the blood can be
carried, it is necessary that the air itself should be taken to all
parts of the body, and this is accomplished by means of tubes
called trachea. Tracheae occur in insects, in spiders, and in
myriapods, all of which are, therefore, called " Tracheates. "
Spiders have eight legs instead of six as in the true insects, and
have the head and thorax combined in one piece or cephalo-
thorax. They have also a decided tendency to the formation of
lung-sacs. The "myriapods" or "centipedes" are more worm-
like in structure, and are furnished with many legs,» — one or two
pairs on each body segment, — sometimes exceeding one hundred
in number.

One tracheal trunk or tube starts from each spiracle, and be-
gins at once to divide and subdivide, sending its ramifications
to all parts of the body, even to the tips of all appendages, so
that air permeates every part of the insect, and tracheal tissue is
present everywhere. The structure of these tubes is interesting :
they consist of a membranous cylinder, stiffened by chitinous
rings or spirals, in appearance very much like the closely-coiled
springs in automatic shade-rollers. This gives rigidity to the
tubes, keeping them always open, while at the same time it
allows the utmost freedom of motion. A series of longitudinal
tubes on each side of the body unite the main trunks from each
spiracle, and in some cases there are transverse tubes joining
the longitudinal tracheae. The entire system is thus connected
in one or two ways, and at a pinch an insect is able to get its air
supply from one spiracle only and from almost any part' of its
body.

Where so many openings into the insect body exist there
must, necessarily, be some arrangement for protecting them and
preventing the entrance of foreign material. There is, therefore,
a great variety of sifting structures, their character depending
largely upon the habits of the insects. There may be a series
of teeth or spurs on each side of a narrow, irregular slit ; a series
of hairs or bristles crossing in front of the opening ; a covering

S7'R('CTCKE .hVD CLASSIFICATIOX. 35

Fig. 17.

Tracheal tube, showing the structure and methods of branching.
Fig. 18.

Spiracles and their protection. — a, plate-like covering 01 white grubs, cross-sec-
tioned at b, to show how air enters; c, a toothed slit; rf, spiracle set on a teat-like
process; d", conical spiracle set in a pit, protected by crossed hairs as shown at y in
section ; g, lip-like spiracle ; h and /, unprotected round or slit-like openings.

Fig. 19.

Fig. 20.

Tracheal gills. — d, leaf-like anal plate or
Agrion ; b, thread-like tuft of Corydalus ; c,
plate-like gill of Ephemera.

Air-bladder at end of
tracheal tube in Bom-
bus.

36 -/^V ECONOMIC ENTOMOLOGY.

shield, beneath which the air must enter, or some other variety
of screen, — all intended to sift out of the air the foreign particles
which might injure the insect. Yet it is through these spiracles
that most of the contact insecticides must act, as will be more
fully detailed hereafter. In many heavy insects there are at-
tached to the tracheae numerous air-sacs or bladders, the object
of which is to reduce the specific gravity of the insect to enable
it to fly more readily. A common example is the well-known
" May-beetle" or "June-bug," which has the entire body cavity
filled with such little bladders. If one of these beetles be watched
when it emerges from its hiding-place early in the evening, it
win be noted that it first crawls to the top of some blade of grass
or twig, or even upon a stone, and rests there a few minutes.
If it be closely observed it will be seen to be pumping in air,—
that is to say, the body pulsates rapidly, and the abdomen seems
continually to increase in size. This is because the insect is fill-
ing the air-bladders, and, as soon as this has been accomplished,
it tries its wings, causing the preliminary "whirr" which is so
familiar to the observer in the early evening of a June day. After
two or three trials the insect becomes confident of its ability to
sustain itself, and flies off" heavily, with a steady hum. If such
a beetle be found at mid-day and thrown into the air it will fall
heavily, and will be absolutely unable to sustain itself in flight
until it has had an opportunity to inflate its air-sacs.

While the vast majority of all insects are air-dwellers, yet many
live underground, a very large number in water, and a consider-
able percentage in decaying or excrementitious matter, Vy-here
pure air is very difficult or impossible to obtain. All sorts of
devices to enable them to breathe under such conditions have
been developed, and in all cases without any essential modifica-
tion of the system. Underground dwellers usually find air suffi-
cient for their needs in the earth in which they live, and the
development here is principally in the direction of more perfect
coverings for the spiracles to prevent the entrance of dirt.

Among insects living in or under water, or spending a portion
ot their life there, we note a great variety of modifications.
Many beetles, and some insects of other orders, have the \ving-
covers dome-shaped, and so closely fitted that they are able to
carry a little supply of air between them and the abdomen.

STRUCTURE AND CLASSIFICATION. 37

When this supply is exhausted of oxygen, the insect rises to the
surface, allows the drop of tainted air to escape, and at the same
time takes in another bubble of pure air. It is then supplied for
another period, varying in length in the different species. Cer-
tain other forms have the body covered with very fine hair, so
dense that the water cannot penetrate it, and these carry a thin
film of air that surrounds them entirely while they are in the
water ; they really do not get wet at all. This air supply must
usually be renewed from time to time ; but occasionally oxygen
is absorbed from the water itself, and the filmy covering is thus
kept constantly purified. Yet other insects have their surface
so absolutely smooth and polished that the water cannot touch
it, and here also a slight film of air may be carried about. There
are other devices to the same end, which it is needless to special-
ize, and we pass to those insects that never come to the surface
at all, and yet secure a sufficient supply of oxygen. These crea-
tures are mostly larvae, and in them we note the development of
structures resembling the gills of fishes in function. That is, in
certain leaf-like or thread-like appendages there are a great num-
ber of very fine tracheal tubes with very thin walls. Through
them the insect absorbs the oxygen contained in the water itself,
and we have exactly the same process that we find in the fishes,
except that here air instead of blood is brought into contact with
the oxygen in-the water. These gill-like appendages vary greatly
in number and shape, but do not differ in function, and will be
further described when necessary in connection with the insects
themselves.

Yet another type of structure is found where the absolute con-
nection with the air really never ceases, — that is to say, the in-
sects have a rigid or an extensile tube attached to the anal end
of the body, and this they keep pointing above the surface while
they walk about on the bottom of the ponds. Insects so pro-
vided are inhabitants of shallow water, and the tubes rarely ex-
ceed an inch or an inch and a half in length. The common
"rat-tailed larvae, " often found in the filthiest of all excrementi-
tious material, are good examples of this method of breathing.
They may be entirely imbedded in the pasty mass ; but the
tip of the ' ' tail' ' is kept above the surface to enable them to
secure fresh air. Finally, we have those cases where insects live

38 AN ECONOMIC ENTOMOLOGY.

in the water, yet get all their air from above it without any power
of storing. This is the case with creatures like the mosquito
larvae, which are unable to breathe without coming to the surface.
They have only a single spiracle at the tip of the body, and are
compelled to rise to the surface at intervals to breathe, and,
having done so, are able to sustain Hfe beneath it for only a short
time afterward.

This much for the general characteristics of the respiratory
system ; it remains to show how it is important from the eco-
nomic stand-point. It has been previously said that the insect
crust is of chitine, which is impervious to a great variety of
ordinarily penetrating substances. It resists alcohol, chloroform,
ether, the light mineral oils, benzine, turpentine, kerosene, and
other similar substances ; acetic acid penetrates slowly and so
does carbolic acid. This accounts for the difficulty which we
find in destroying many insect eggs, for there are no openings in
them that are sufficient for the penetration of these substances,
and they are unable to act through the egg-wall itself To get a
liquid insecticide to kill an insect by contact, it must be forced
into the body through the spiracles, or they must be so gummed
or clogged as to close them completely, thus preventing the in-
sect from breathing at all. Kerosene is the most reliable of the
penetrating liquids, and even where the spiracles are well pro-
tected this material penetrates into the smallest openings. It
has the advantage of actually wetting everything ; that is to say,
it is not repelled by small hairs, as globules of water would be,
and therefore, as it really comes into direct contact with them, is
enabled to work its way through the spiracles. That is what
makes the kerosene so much better than any watery mixtures
alone ; for whatever the material extracted by or dissolved in
water, it may perhaps be repelled by the insect body, and never
have the opportunity of exercising an effect. The various soaps
act in another way ; as the moisture evaporates, a film of sticky
or gummy material remains which clogs the spiracles, and thus
chokes the insect by depriving it of air. Soapy mixtures also
wet and stick well to insects through the caustics they contain,
and which have the power of cutting the repellent material of
their bodies.

In some kinds of insects the spiracles are so feebly protected

STRUCTURE AND CLASSIFICATION. 39

that dry insecticides penetrate them readily, if finely ground ;
and all such are effective in proportion to their fine mechanical
condition, enabling them to enter the tracheae through the sieve
of the spiracles. Thus, sawfly larvae or " slugs," like the " cur-
rant-worm" and " pear-slug," succumb readily to dry hellebore,
pyrethrum, or even fine road dust. Many parasites may be
reached in this way, and some animals and all fowls keep them-
selves tolerably free from vermin by frequent dustings. This is
not the place to go into the eftectiveness of insecticides ; but it
may be repeated that contact poisons usually act through the
spiracles only. Dry powders are effective in proportion to their
fineness and to their peculiar poisonous properties ; liquids are
effective in proportion to the thoroughness with which they are
applied, and to their penetrating or clogging characters.

Caustics and chlorides act differently, and may actually corrode
a thin insect crust. But this matter also comes more appro-
priately under another heading, and will not be further discussed
here.

CHAPTER VI.

NERVOUS SYSTEM AND SENSES OF INSECTS.

The nervous system in insects consists of a series of white
disks or ganglia lying on the bottom of the body cavity, con-
nected by a double cord extending the full length of the insect.
Insects have no true brain, as do the higher animals, and the
ganglion situated in the head, which is usually called " brain," is
larger than the others simply because of the great number
of special organs — eyes, antennae, and mouth parts — that must
be innervated from it. In its structure it is precisely like the
other ganglia, though in some of the social types there is an
appearance of specialization. Nerve-fibres start from all ganglia
in every direction, and all parts of the body are reached ; the
nervous system in one direction being exceedingly well devel-
oped. In the larval forms and in the lower types, a ganglion is
present in every segment of the body, including the head ; and
thus each segment contains its own nerve-centre, the cords from

40

AN ECONOMIC ENTOMOLOGY.

which are primarily sent out to the organs and appendages lying
within that particular segment. In adults there is a tendency
to a union of the thoracic gangUa, and in the abdomen two are
usually confluent toward the anal end of the body. The digestive

system is usually in-
FiG. 21. nervated by a spe-

cial ganglion, and
has its own, partly
distinct system. In
the higher insects the
thoracic ganglion is
the most important
in the body for the
life of the insect, and
if this be cut or
destroyed the insect
dies at once. Any
other ganglion may
be cut without pro-
^ ducing immediate

, , . , , , . death, and the brain,

Nervous system of the honey bee at a, and of its

larva at b. usmg that term for

the ganglion con-
tained in the head, may be entirely removed without necessarily
killing the insect itself

While, as stated, the nervous system is well developed and all
the organs are well furnished with nerve endings, yet it is prob-
able that insects are not particularly sensitive. The oft- cited
case of the butterfly that was captured and pinned while alive,
then escaped from the collector, and returned at once to its
feeding among the flowers without apparent inconvenience, is
known to most readers. If a dragon-fly be captured and held
by the wings loosely, so as to prevent its escape but not to
injure it, and the tip of its abdomen is then presented to its
mouth, it proceeds at once to eat it as far as it can reach, with-
out any apparent knowledge of what it is doing. It will thus
devour, with the greatest portion of the abdomen, half its diges-
tive system, nearly half its entire nervous system, and a large
part of its heart ; yet, if it be then released, it will fly ofl", little

STRUCTURE AND CLASSIFICATION. 41

the worse, except that it is unable to balance itself. Insects may
lose a considerable number of their members without apparent
inconvenience : a tly may lose a leg or two without seeming
in the least worried, or one or both of its wings may be torn off
without causing death or even a manifestation of pain.

I once made a series of experiments to test, not so much the
sensibility of flies, as the effect that cutting the various organs
would exercise upon it. I found that if I cut off the abdomen
completely, the fly would live for twenty-four hours thereafter ;
with practically no digestive system, with very little nervous
system, and with most of its heart gone. Turning the matter, I cut
off the head, and found that it would live without a head for just
about as long a time as it would without an abdomen. Of course
death was bound to result from this mutilation in time, but the
interesting feature is that no apparent symptom of pain was
developed. I found, however, that just as soon as I cut the large
ganglion in the middle of the thorax I terminated life. What-
ever sentimental feeling there may be in the matter of causing
unnecessary pain, there is no reason to believe that insects have
any well-developed sensitiveness, as we understand that term.
The character of the insect nervous system is so entirely different
from our own that we are left without real guides in our interpre-
tation of the various sensory structures. Man judges most things
by himself, and where this guide fails he is at a loss, and cannot
be certain that he interprets what he sees correctly.

The eyes are perhaps the most prom.inent and best understood
of the organs of special sense. They are of two kinds, simple
and compound, and both may be present in the same species.
The simple eyes are termed ocelli, and consist of a more or less
convex, often bead-like lens or facet, by means of which an image _
is thrown on a retina, and thus transferred to the perceptive
centres. In larvae simple eyes, or ocelli, are the rule, except in
types with incomplete metamorphosis, where the eyes resemble
those of the adults. In larvae the simple eyes may be situated at
almost any point on the head ; but usually they are grouped at
the sides : sometimes only a single ocellus at each side, sometimes
a group of a dozen or more, forming the rudiments of a com-
pound eye. In adults there are rarely more than three ocelli,
usually situated in a triangle either close together or widely sep-

42

AA^ ECONOMIC ENTOMOLOGY.

arated ; or there may be only two, one on each side, near the
base of the antenna, as is usual in butterflies and moths.

Fig. 22.

Sensory organs of insects. — A, one element in eye of a roach ; B, section of compound
eye ; C, organs of smell in May-beetles ; D, sense organs in abdominal appendages ; E,
sensory ear ; F, ear on foreleg of locust ; (7, ear found on the basal segment of grass-
hopper abdomen. .All greatly enlarged.

Compound eyes are so termed because they are made up of a
great number of simple eyes, or ocelli, set very close together.
If the head of a bee or house-fly is examined, it will be noted
that the brown eyes occupy a very large portion of its surface,
and if one of those eyes be viewed under the microscope it
will be found to be faceted, or to consist of thousands of little
hexagonal disks, resembling in appearance the top of a honey-
comb. Each one of these facets represents a complete eye,
capable of forming an image upon its own little retina, and the
combination of all the little retinal pictures is what a fly or other
insect sees. In some cases the eyes are so enormous that the
in.sect can see everything going on in front, at each side, above
and beneath, and even back, except directly behind it. It is
difficult for us, who are able to see in one direction only, to

STKUCrURK AND CLASSIFICATION. 43

imagine the sort of picture an insect perceives, and we are by no
means certain how well or iiow poorly it really does see. We know
only that larval forms and low types, provided with ocelli only,
see very feebly and indefinitely, and can do little more than dis-
criminate between light and darkness. Many insects have no eyes
at all, living under such circumstances as to make them useless.

That insects hear follows almost inevitably from the fact that
many of them "sing," — that is, produce some sort of noise.
What those organs of hearing are is not so certain in all cases,
nor where they are situated, since we cannot confine our search
for ears to the head alone. In the Orthoptera they have been
located with a reasonable degree of certainty : in the grasshopper
the ears are on each side of the basal segment of the abdomen,
while in the locusts and crickets they are on the anterior tibiae.
Essentially, these ears consist of a tense membrane stretched over
a cavity, and connected by means of little processes, correspond-
ing somewhat to the bones of the human ear, with a bulb-like
vesicle and a large auditory nerve. In most other orders no
similar structures are found, and the sense of hearing is located
in the antenna^, or feelers, of which more will be said later on.

Insects are able to discriminate as between foods, and the sense
of taste is undoubtedly developed to some extent ; but the taste
which seems agreeable to their sense would be to us, in many
instances, the vilest conceivable. No true tongue, as this organ
e.xists in the vertebrates, is found among insects ; but on the up-
per side of the lower lip there is often a finely papillate surface, set
with little fleshy pegs and processes communicating with nerve
fibres, and this represents the nearest approach to the tongue
of the higher animals. It is called the hypopharynx , and is
not always present. Beneath the labrum, or upper lip, we often
find a separate, flat, similar piece, and this is the epipharynx,
corresponding in function to the palate of the higher animals.

Nothing resembling a nose is found among insects, and yet
the sense of smell seems very highly developed. Insects often
discover their food with unerring certainty, even when concealed
from sight. Among the nocturnal species, where sight can play
but a small part at best, the sense of smell seems most highly
developed, and usually more in the male than in the female.
This is due to the fact that the males, as a rule, seek their mates,

44

AN ECONOMIC ENTOMOLOGY.

and so keen is this sense that they discover the presence of the
female, even when confined in a breeding-cage, if a window be left
open. Sometimes male wood-borers will sit around a spot on the
bark for a considerable time awaiting the emergence of a female,
which their keen sense tells them is fully developed and ready to
make her way out. Carrion feeders discover their food when con-
cealed from sight, and almost before decay has set in. So far as
we have been able to ascertain, the olfactory organs are situated
in the antennae, and form small pits or depressions, from which
usually arise specialized hairs, bristles, or pegs, as the case may be.

Fig. 23.

Sensory organs of insects.—^, sensory pittings in plant-louse antenna;; B, organ of
smell in May-beetle; C, same in wasp; />, sensory organs in Termes flavipes ; E, F,
organs of taste in a wasp ; G, organ of smell in grasshopper ; //, sensory depressions
on the tibia of Te>-mes ; /, terminal joint of antenna of an ant ; K, section through the
antenna of a honey-bee, showing supposed olfactory organs. All greatly enlarged.

The sense of touch is located popularly, and I think correctly, in
the antennae ; but it is quite certain that tactile hairs exist all over
the body of the insect, more developed in some than in others,
and most, perhaps, in larval forms. These structures always
consist of specialized hairs or bristles, and end in a nerve cell.

S'/'RLVrrA'E AXD CLASS /J- /CAT/ OX.

45

It is probable that in the antennae we have a sense of percep-
tion which is able to discriminate between atmospheric vibrations,
and in this way the same or similar structures may serve as organs
of hearing, smell, and touch. That is to say, it is probable that
there is no such sense in insects as the power to discriminate
between smells, but that each is able to recognize certain definite
kinds of odors which do produce an effect upon it. So it is also
likely that only sounds of certain descriptions are recognized,
and these sounds may even be such as the human ear is not
capable of perceiving. We are far from understanding the senses
of insects, but the above outline is all that is necessary for our
present purpose.

CHAPTER VII.

THE REPRODUCTIVE SYSTEM.

The rate of increase among insects is often very great. It is
nothing unusual to hear a farmer say that on one day his plants
were free from insects, or nearly so, while a week thereafter
everything seemed to be swarming. As a matter of fact, this is
frequently due to a failure to observe the insects in the first place,
either in the stage in which they then existed or on account of
their small numbers ; but it remains true, nevertheless, that in-
sects are often exceedingly prolific. The number of eggs laid
by a female often runs up to one thousand, or even more, while
the number of eggs within the power of a Termite queen is be-
yond all calculation. If it were not for their natural checks, in-
sects would soon overrun the world. In one year not one green
thing would be left on the face of the earth, and not one living
being other than insects would exist. These natural checks con-
sist largely in sudden changes or abnormally high or low tem-
perature, in unusual moisture or drought, or in a combination
of two or more of these factors. Diseases often attack insects,
and genuine epidemics occur, sweeping off millions in one stage
or the other. The natural enemies are legion ; many vertebrates
are largely dependent for their food upon insects, and this is
especially true of birds and reptiles, some of which subsist upon
insects exclusively. A large proportion of the insects themselves

46

AN ECONOMIC ENTOMOLOGY.

Fig.

are predaceous, and live upon others of their kind ; great num-
bers are parasites, their prey being other insects of all orders,
and in this way forms that depend upon plant life for their sub-
sistence are kept within definite bounds. These bounds, though
they may vary from year to year, never change much except
where man interferes. This subject will be touched upon in an-
other place more fully.

Except in rare instances insects are of two sexes, male and
female, and we nowhere find among them true hermaphrodites.
In the plant-lice and gall-wasps we have apparent exceptions ;
but these are only apparent.

In the female the most prominent sexual organs are the ovaries.
These consist of two sets of tubes, one in each side of the abdo-
men, usually below the digestive system, united
at their base into one larger tube called the
oviduct ; the two oviducts unite, just before
opening outwardly, into a single chamber
called the vagina. The vagina opens out-
wardly at the end of the body, sometimes with-
out special modification, sometimes by means
of a flexible or extensile tube, sometimes as a
long, rigid cylinder, and occasionally in the
form of a sting. These structures, be they
rigid or otherwise, are always called ovipositors,
and their function is to place the &^^ into the
position necessary for its best development.
Associated with this system are a number of
glands, the use of which is either to give a
sticky coating to the &%^, enabling it to adhere
to the leaf or other point at which it is laid, or
to supply a poisonous secretion, where such is
of development, with Hcccssary lor dciencc or lor stupefymg prey.
nutritive cells, WW, be- There is also a little sac, attached by a slender
cIpTade^orovi'duct^; ^uct to the vagiua, at about the point where
the two oviducts unite. This is the seminal
receptacle, and in this is received the seminal
from it the eggs are fertilized as they pass from
the oviduct into the vagina on their way through the ovipositor.
In some insects these receptacles are very large, especially where

Ovarian tubes of one
side, in Polistes, show-
ing eggs in all stages

vag, vagina.

fluid of the male

STUrCTlRE AXD CLASSI/-7CAT/0A.

47

copulation takes place in the fall, and the female, living through
the winter, does not begin to lay eggs until some time in spring.
The eggs have at one end small openings termed niicropyles^ and
through these the spermatozoa find their way into the ^^^ to
fertilize it. In the ovarian tubes a variable number of cells are
developed, and these grow rapidly, each cell eventually forming
an egg. The number of tubes and the number of cells in the
tubes vary within wide limits in the different species. In some
they are rigidly limited, and the insects are able to lay only a
definite number of eggs ; in others the cells are so numerous that
a definite number seems unlikely. Before the female has been
impregnated the ovarian tubes are \ery slender and occupy only a
little space in the abdomen. When the eggs develop, however,
the ovaries increase in size until, finally, the abdomen is almost
entirely occupied by them, and is often enormously distended.

In the male the ovaries are replaced by the testes, which also
are more or less coiled tubular structures, and these tubes, like
the ovaries, unite to-
gether on each side into ^^^- ^5-
a larger tube, which in
turn are combined into
a single organ, usually
more or less horny in
structure, — the penis.

Reproduction among
insects is, therefore, in
its essentials, like that
of the higher animals.
The only difference is
that as the life period is
shorter, the eggs must
all be laid within a defi-
nite time, and they are
v&ry much greater in
number. It further
proves that we have a
definite development in

insects as in higher animals, and that with them also, like pro-
duces Uke,— that is to say, the product of the €:gg when fully de-

Male organs of May-beetle. — One side only beyond
the ductus ejaculatorius, duct, ejac; glni., mucus
glands; ves. sem.,s^ram2X vesicles; vas. de/., vasa
deferentia.

48 .'LV ECONOMIC ENTOMOLOGY.

veloped will be like the parent that laid it, and never anything
else. Insects are as a rule unable to reproduce until they have
reached the adult stage, and the few apparent exceptions may
not be real when all the factors are understood. An insect, when
once adult, never changes into one of a different kind ; so a
beetle can never change into a cricket, nor a small fly into a
larger one.

CHAPTER VIII.

GROWTH AND METAMORPHOSIS.

Insects grow only in the larval stage, and moult, or change
their skin, every time there is an increase in size. As has been
stated, the insect crust is rigid and inelastic, and extension is
possible only by the expansion of the membrane between the
rings. When a growing insect reaches the extent of the elasticity
in its covering, a new skin forms beneath the old one, and the
latter splits, allowing the newly-clad and much larger specimen
to crawl out of it. In this respect insects resemble crabs, lobsters,
and other crustaceans.

The terms larva, pupa, and adult have been several times used
in the previous chapters, and need more explanation. Most
insects undergo, in the course of their life, a series of changes or
transformations, in which their form, appearance, and habits are
often so diverse that the different stages could not be recognized
as belonging to one species without definite, continued observa-
tion. These changes are termed metamorphoses, and they
include the egg, larval, pupal, and adult stages. With few
apparent exceptions, all insects begin in an egg stage, and the
method in which this egg is developed has been already described.
In this stage, whether it be long or short, the creature is unde-
veloped and quiescent, except for the changes going on within,
and which do not result in outward movement. In rare cases
the eggs are not extruded from the body of the insect, but fertili-
zation takes place in the ovary, the larvae hatching within the
abdomen of the mother.

From this egg comes in due time a larva, a minute creature

STRUCTURE AND CLASSIFICATION.

49

which may or may not resemble the parent that laid it. Assum-
ing that it does, it is without trace of wings. It grows apace,
moults as often as necessary, and at last attains very distinct wing
pads. It is now in the pu[)al stage, and with the next moult the
wings become fully developed. It is then adult and fitted to
reproduce its kind. This sort of metamorphosis is said to be
incomplete, because there is no inactive stage, and because there
is always a close resemblance in all stages. The larvae are quite
usually termed nymphs, and differ from the adults only in size, in
the absence of wings, and in the undeveloped sexual characters.
A peculiarity of this method of growth or moulting is worthy of
incidental mention. When the insect moults, it is not the outer

Fig. 26.

Moulting of a grasshopper.— o, nymph ready to change; b, the skin split along the
back and the adult emerging ; c, continues the process, and at d, the adult insect
drying out.

skin alone that is aftected : all the most delicate mouth parts with
their hairs and processes are cast and replaced by a new cover-
ing ; the lining of a large proportion of the digestive system
is shed, and the inner coat or surface of the tracheal tubes is
renewed, so that practically the insect gets, in part, a new diges-
tive system and a new breathing apparatus, every time it increases
in size. The number of these moults varies in the different orders,
and even in species of the same order. There may be as few as
three or four, and there may be twenty or more. We can some-
times modify the normal number by changing the circumstances
under which the insects live. Thus, the larva of the common
Dermestid found in museum cases normally moults four times

4

5°

AN ECONOMIC ENTOMOLOGY.

before it is ready to change to a pupa. I have confined several
larvse in vials, closed them tightly with rubber stoppers, and sup-
plied a small amount of food. In these dry vials larv« have
lived for months, in one case more than a year, and apparently
as a mere pastime they moulted at intervals, so that in one vial
there were eight or ten cast skins, more than doubling the ordi-
nary number of changes. Withal the insects did not increase in
size, simply because no more food was supplied.

Where the metamorphosis is complete, there hatches from
the Q.^% a grub, caterpillar, slug, maggot, or other crawling or
wormlike creature, quite unlike the parent. Growth continues,
as before, by moulting, until the full size has been attained, and
then feeding ceases. The larva now seeks some retired spot,
sometimes spinning a silken covering termed a cocoon, and then
changes to a chrysalis or pupa. The term chrysalis is used in
the butterflies, where it is free and often prettily ornamented, and
the term pupa in most other cases. In this stage it is inactive
and rests quietly for some time. The character of the future in-
sect is usually more or less clearly defined, but occasionally it
resembles neither the larva that formed it nor the adult insect
which is to come from it. In due time the adult emerges as a
butterfly, moth, beetle, fly, or bee, and no trace remains of the
previous larval condition. Insects never grow after they reach
the adult stage, but remain of exactly the same size as when
first they emerged from the pupa. Thus, as has been indicated
in the previous chapter, large flies are never the parents of small
flies, nor do small flies ever grow to become larger flies.

This cycle of change in an insect is termed its life history, which
it is sometimes very difficult to work out. Scarcely two species
are alike in habit during all their lives, and a complete knowledge
of the full life cycle and the habits in all stages is essential to an
intelligent application of remedial or preventive measures.

It is often possible to reach an insect easily in one stage, or at
one period, where it is naturally protected during all others. So
we may, sometimes, by a little change in farm practice, or by
taking advantage of some preference on the part of the insect,
avoid injury. To ascertain all these facts and to suggest the
treatment indicated, is the work of the economic entomologist.
Watching the transformations of an insect is a delightful task,

S TR L X '7'C RE AND CLASSIFICA TION.

51

and one that can be easily accomplished in most cases by any
one possessing a Httle patience. In leaf- feeding insects all that
is necessary is to bring in a supply of food with the larva upon
it, and keep it in a box rf can-e, renewing from time to time, so
that fresh food may be always available. In the bottom of the

F'iG. 27.

^^

A breeding-cage of the Riley pattern.

box there should be three or four inches of clean sand for the
benefit of those forms that go underground to change to a pupa,
and in due time the caterpillar or slug will, under the observer's
very eyes, change to a butterfly, beetle, or other insect, accord-
ing to the character of the larva.

F>AR1^ II.
THE INSECT WORLD.

CHAPTER I.

GENERAL CLASSIFICATION.

Those structures which are of economic importance and, in-
cidentally, those that are used in classification have been described
in the first part.

Classification is the arrangement of the insects into series
which are so related to each other that a species never before
seen may be recognized, and its place ascertained from certain,
easily discernible, structural characters.

Insects that agree in structure usually have similar habits, and
by placing an example into its systematic position, the probable
life cycle becomes also known, and its exact life cycle can be
more easily and intelligently traced out.

The divisions used are orders, families, genera, and species.
The term sub- may be prefixed to either, to indicate a division
not marked enough to claim full rank.

A species is the ultimate division, and consists of individuals
which agree with each other in appearance, structure, and life
history, mating freely and producing progeny, which resemble
the parents. An assemblage of such species agreeing in generaJ
characters forms a genus, and this is a more or less uncertain
divi-sion, depending somewhat upon the opinion of the systematic
student. A series of genera agreeing in form, structure, and
life history makes a family, and families are united into orders.

For the division into orders, use is made of wings and mouth
structures and of the transformations.

For convenience in ready classification the Linnaean orders are
here adopted, though some of them have been properly sub-
52

THE INSECT WORLD.

53

divided. The new orders are referred to, however, in the proper
place.

Lowest of all are the 77iysa intra, ineludinu;^ "bristle-tails,"
' ' spring-tails, " " fish-moths, ' ' and the like. They never become
winged or develop even a trace of wings. The mouth parts are
small, retracted, usually formed for biting, but sometimes so
undeveloped as to be almost without type. The metamorphosis
is incomplete ; indeed there is only a simple increase in size, and
nothing really worthy of the term development. In most cases
the abdomen bears a pair or more appendages at the tip, from
which some of the common names are derived.

Next come the Neiiroptera, or nerve-winged insects. These
have four well-developed wings, membranous, more or less
transparent, and so crossed by numerous veins that they seem
reticulated or netted : from which character they derive their
name, which means nerve-winged. The mouth parts are man-
dibulate, usually well developed, but sometimes almost obsolete.
In its broadest sense the order includes " May-flies," "dragon-
flies," "caddice-flies," "white ants," " stone-flies," " lace-wing
flies," and the like. There are, however, two types of meta-
morphosis,— one complete, the Neiiroptera proper, and the other
incomplete, the Pseudo-neiiroptera. It is here that most of the
new ordinal divisions have been made.

A step in advance are the Orthoptera, or straight-winged
insects, such as roaches, crickets, katydids, and grasshoppers.
They have two pairs of well-developed wings, — the first or ante-
rior usually narrow and a little thickened or parchment-like; the
second or posterior broader, plaited or folded like a fap beneath
the anterior pair. The mouth parts are formed for biting, and the
metamorphosis is incomplete.

The order Heiniptera, or "half-winged" insects, includes all
the true ' ' bugs ;' ' and to members of this series only the term
"bug" is properly applied, according to entomological opinion.
The order is always distinguishable by the mouth structure, which
is haustellate, and consists of a jointed beak, concealing two pairs
of slender, pointed lancets. The metamorphosis is incomplete.
The term Hemiptera, or " half-winged," is derived from the fact
that in the typical series the primaries are thickened at base and
thin or membranous at tip. In it we have such creatures as the

54

AN ECONOMIC ENTOMOLOGY.

"chinch-bug," "squash-bug," and others of equal note. The
term Homoptera, or "similar-winged," is used for that series in
which the fore-wings are uniform in texture, as in the plant-lice
and Cicadas.

The order Coleoptera contains the beetles, and the name, mean-
ing " sheath- winged," is due to the fact that the anterior wings
are hard and horny, unfitted for flight, and used only as a sheath
or covering for the posterior pair. The mouth parts are man-
dibulate, and the metamorphosis is complete.

An easily recognized order is the Lepidoptera, or "scaly-
winged," including the butterflies and moths. Here wings and
body are covered with minute scales, easily rubbed off and
resembling colored dust. The mouth parts are haustellate, and
form a coiled tongue, which is usually concealed beneath the
head, but can be readily extended at the will of the insect. The
metamorphosis is complete.

Equally recognizable are the Diptera, or "two-winged" flies.
The single pair of wings is characteristic, and with it are asso-
ciated mouth parts varying much in type, but never mandibulate
nor forming either a coiled tongue or jointed beak. The meta-
morphosis is complete.

The Hymenoptera, or "transparent winged" insects, include
bees, wasps, ants, and the like, and stand at the head of the
Class Insecta. They have two pairs of transparent wings, with
only a few veins ; the posterior smaller than the anterior. The
mouth parts are mandibulate, but the tongue is often developed
as a lapping organ, and sometimes greatly enlongated. The
metamorphosis is complete.

To show the differences succinctly the following table may be
of use :

Insects which never become winged, have the mouth feebly developed

and the metamorphosis incomplete Thysanura.

All others are winged :
With four transparent wings, which are net-veined and flat; mouth
parts mandibulate and well developed ; the metamorphosis, either

incomplete Pseudo-neuroptera.

or complete Neuroptera.

With the fore-wings narrow and somewhat thickened ; the posterior
folded fan-like, or plaited ; mouth mandibulate ; transformations
incomplete Orthoptera.

THE INSECT WORLD. 55

With fore-wings thickened at base, thin at the tip ; mouth parts form-
ing a jointed beak ; transformations incomplete • . . . Hemiptera.

With the fore-wings uniform in texture ; mouth parts and transforma-
tions as before Homoptera.

The fore-wings are horny, and useless for flight, serving only as a cov-
ering for the posterior pair ; mouth mandibulate ; metamorphosis
complete Coleoptera.

All the wings and the body covered with scales ; mouth parts developed
into a long coiled tongue ; transformations complete Lepidoptera.

The wings transparent, with only a few longitudinal veins ; mouth
mandibulate, the tongue formed for lapping ; transformations com-
plete Hymenoptera.

Two wings only ; mouth parts haustellate ; transformations complete

DiPTERA.

CHAPTER II.

THE THYSANURA.

Spring -tails. Bristle-tails, Fish-moths, etc.

Under this term are grouped a number of lowly insects which
never become winged, and can hardly be said to have any real
transformations. Most of them are small, soft bodied, with
feebly developed mouth parts, and live in damp earth, among
decaying vegetable matter. Some live under bark of dead or
decaying trees, or in decaying wood, while in rare instances spe-
cies are found preferring dry and warm localities. Among those
that live in damp places are forms without eyes, and with no de-
veloped tracheal system, the necessary oxygen being absorbed
through the skin itself Compound eyes are developed in a few
in.stances only, though ocelli are usually present.

Peculiar to the order are certain abdominal appendages. In
some cases these are in the form of rudimentary abdominal legs,
indicating a relationship to the Myriapods or Centipedes ; but
more often they consist of bristles or filaments attached to the
anal segment. In the simplest form they consist of long, many-
jointed appendages, whose function may be tactile, similar to
that of the antennae.

A good example of this type is the little creature known to

56

AN ECONOMIC ENTOMOLOGY.

Fig. 28.

house-keepers as the "fish-moth," or "silver fish." It is one
of the few species tliat prefers a dry, warm locaHty, and is found

in cupboards and closets, hiding in
crevices, and running rapidly when
disturbed. It is about one-quarter
of an inch in length, oblong, a little
pointed towards both ends, and has
the body covered with minute, sil-
very-white, glistening scales. It is
one of the largest species belonging
to the order, feeding upon starchy
substances and food remnants. It
sometimes becomes troublesome in
libraries, gnawing the calendered
surface of leaves and bindings and
defacing them. The insect can
scarcely be said to be injurious, but
it is often annoying, and may be
driven out by a free use of pyre-
thrum dusted in corners and crev-
e^

A much more common type is the
spring-tail," so named from the
fact that the anal appendages consist
of two short, bristle-like processes,
arranged to enable the insect to leap
or spring. They are normally bent
under the body, held in place by a
catch-like organ until the insect de-
sires to move suddenly, when the
catch or spring is released, sending
the insect forward a surprisingly long
distance. When excited it progresses by a series of rapid leaps
of this kind, its course being decidedly erratic because no two of
the springs are made in the same direction.

"Spring-tails," or Podurids, are found in moist localities,
wherever decaying vegetable matter occurs. In manure beds
they often occur in millions, and on warm days may come to the
surface in astounding numbers. I have seen a forcing bed cov-

Bristle-tail or fish-moth ; Lepisma sp.

THE INSECT WORLD.

57

ered nearly half an mch in depth by a solid mass of these little
creatures not one-sixteenth of an inch in length. Frequently a

Fig. 29.

Fig

Papyrus species : showing spring curved under the body.

sudden rise of water on meadow or bog land drives them out of
their hiding-places, and they leap about on its surface for a time
as readily as they do on land. I have seen, on cranberry bogs
reflowed late in May, square rods of the surface so densely cov-
ered that nothing of the water was visible.

They are often found in damp cellars, on any vegetable matter
stored there, and are sometimes ac-
cused of promoting decay. In the
fields a cut potato placed underground
piay attract dozens of specimens that
feed upon the juices of the raw sur-
face, and they have been therefore ac-
cused of producing scabby potatoes.
They are of all colors, but usually
slate-gray or yellowish, the markings
sometimes quite pretty and distinct.

As a matter of fact, these insects
are never injurious. Healthy vege-
table tissue is not attacked by them,
and their mouth parts are adapted for
feeding on soft or moist tissues only :
hence a decayed or bleeding spot at-
tracts them. They are sure to occur in manure and on manured
land, and can be kept out to a large extent by using only mineral

A Podurid, or spring-tail, found on
manure beds.

58 AN ECONOMIC ENTOMOLOGY.

or " commercial" fertilizers. In the manure itself they are bene-
ficial rather than otherwise, hastening its decay by changing the
form of the more resisting portions.

It sometimes happens that, when found associated with decay
or rot of stored produce, the insects are accused of causing it ;
but they always follow and never precede or cause the diseased
appearance.

CHAPTER III.

THE NEUROPTERA AND PSEUDO-NEUROPTERA.

May-flies, Dragon-fiies, Stone-flies, Caddice-flies , etc.

The old term Neiiroptera comprised all insects with four more
or less transparent wings, reticulated or netted with numerous
longitudinal and transverse veins, and the mouth parts formed
for biting. As thus defined the order was easy of recognition,
and, practically, the division is convenient here, for nowhere in
this series are any species injurious to field crops. We find
troublesome species among the parasites, and the Termites, or
" white ants," are injurious under some circumstances ; but, as a
broad statement, subject to a few exceptions, it is correct to say
that no Neuroptera are injurious to field crops, and no appre-
hension need be felt whatever the numbers in which they may
appear.

It was early found that under this term insects quite different
in life habits were included, some having complete and some in-
complete metamorphoses. The order was then divided, the term
Fsezido-neiiroptera being applied to those forms in which the
transformations are incomplete. The division is a good one ;
but, as there is nothing in the adult to indicate to the tyro the
nature of the changes it undergoes, it was not always easy to de-
cide to which order a given insect belonged. More recently the
series has been yet further divided, and we have now somewhat
compact groups of net-veined insects which may be recognized
without much trouble. These will be referred to in order under
their modern names.

THE INSECT WORLD.

59

Fig. 31.

Order EPHEMEROPTERA.

This order inckules what are known as "May-" or "day-
flies," the names indicating either the
time at which they first appear or
the brief period of their adult Hfe.
"May-flies" occur most abundantly
during spring or early summer, in the
vicinity of lakes, ponds, and rivers.
They are readily recognized by their
fragile body, terminated by two or
three long, thread-like appendages, and
by their large, frail wings, the posterior
much smaller than the anterior. They
fly at night, and are readily attracted
to light, dozens being often seen hov-
ering around a single street lamp. I
have seen bushels of them at the base
of electric lights on the banks of the
Ohio, and the shores of the Great
Lakes are sometimes covered with
heaps six inches or more in depth, so
that the stench from the decaying
bodies becomes nearly insupportable.
The head is large, the eyes are round
and prominent, and the forelegs are
conspicuously long and stout ; but the

feelers are reduced to mere rudiments, and the mouth parts are
atrophied and utterly useless for feeding purposes.

In the May-flies we have the survival of an ancient type, their
generalized structure indicating a low place in the scale of -devel-
opment. The eggs are laid on the surface of the water and sink
gradually to the bottom. From them hatch narrow, elongate-
oval, more or less flattened larvae, furnished laterally and some-
times at the end of the body with gill-tufts, living in the mud
ooze of river and lake bottoms, under stones, or among aquatic
plants. They feed on all sorts of minute animal life, and prob-
ably also upon the low forms of vegetation on submerged stones
or sticks. They grow slowly, moult frequently, and live from

Mav-flv and its larva.

6o AN ECONOMIC ENTOMOLOGY.

one to three years in this condition. Wing-pads gradually
appear, and eventually the adults emerge and fly away, only to
shed their skins once more in the very act of flight. I have seen
their delicate, pure- white exuviae float about over the Ohio River
in such numbers as to resemble a fall of snow. This moulting of
the adult is peculiar to the Ephemerids, who mate soon after it
occurs, deposit their eggs, and before morning perish, — their
life-work accomplished.

Not all forms are so short-lived, however, some requiring sev-
eral days to complete oviposition ; but their inability to feed
indicates a brief existence at best. The number of species is large,
and the number of specimens immense, indicating an active,
aquatic insect life at least as great as that found in the air or on
the dry land. While the larvae feed on smaller creatures, they
are in turn devoured by fishes, who find in them an important
article of food, and in this view only are they of any economic
importance.

Order ODONATA.

Under this head come the dragon-flies, or, as they are often
termed, "devil's darning-needles," "spindles," or "snake-
doctors." Many superstitious beliefs are connected with these
insects, and there is a general indisposition to handle them, be-
cause of their supposed ability to sting. The insects are common
about ponds and streams, flying rapidly over the surface of the
water, occasionally darting down to touch its surface, and delight-
ing always in the bright sunshine.

The body is long and slender, fitted with an enormous head
principally occupied by the eyes, and with two pairs of long nar-
row wings, which are similar in size and appearance. In some
species there are leaf-like appendages at the end of the abdomen,
and these are erroneously supposed to be weapons of offence.
The legs are stout, clothed with spines and spurs, as well as with
long claws at the tip. The mouth is formed for biting, the man-
dibles and maxillae being greatly developed and sharp-toothed,
for tearing their prey.

They are, as has been indicated, predaceous, and capture their
food during flight, their powerful wings and legs enabling them to
overtake and grasp any creature that comes within the range of
their huge eyes. Flies and mosquitoes are the usual victims, and

THE INSECT WORLD.

6i

hence the term "mosquito hawk" has also been apphed to
them.

It has been suggested that dragon-flies might be artificially
propagated to lessen the mosquito pest ; but this is not feasible,
because they fly only during the day, while the mosquito is
decidedly more a creature of the night. No dragon-fly volun-
tarily remains in woods, except along streams and in open glades,
yet here mosquitoes lurk by the million. The proposition looks
well at first sight, but is not practical.

KiG. 32.

Draguii-fly arnl its ile\ clopment. — Lar\a ami pupa feeding at i and 3; 2, nymph ready
to change ; 4, a pupa skin from which 5, the adult, has emerged.

The early stages are passed under water, and the larvae are
ugly creatures, somewhat resembling the adults, but without
wings. They move sluggishly among the aquatic vegetation, or
on the mud of the bottom, strongly resembling the latter in
color. They do not swim readily, but some are able to propel
themselves by drawing into the posterior part of the digestive
tract a quantity of water and then expelling it forcibly. This
process really answers a double purpose, for this same tract is
supplied with numerous fine tracheal tubes through which oxygen
is drawn from the water : two functions, respiration and locomo-
tion, being thus curiously combined. Respiration is also carried
on by means of leaf-like anal appendages, in which trachea ramify
in all directions, forming gill-like structures. As the larvae grow,
wing-pads appear, and when these are fully developed the pupal
stage has been reached ; the insects continuing active, however.

62

AN ECONOMIC ENTOMOLOGY.

until ready for the change to the adult. Then they crawl up the
stem of some water plant, or upon a projecting stone, and soon
the skin splits and the imagos_emerge. A few minutes suffice to
harden and dry the newly-developed adults, then with spread
wings they sail away on a new career, in a new medium.

In habit the larvae are as predaceous and voracious as the adults,
and their prey consists of any aquatic forms which they can cap-
ture,— mosquito larvae forming quite a staple article of diet. It
has been already indicated that they are not very active' creatures,
and prey is captured by simply waiting in the mud or on a mossy
stone until it comes within reach. Their color renders them
almost invisible under such conditions, and nature has furnished
a remarkably extensile mouth structure, by means of which they
are able to reach out some distance and seize whatever creature
may be passing near. It is the labium, or lower lip, that is
modified for this purpose, and is supplied with a double hinge
which can be straightened out rapidly to bring into play a pair of
large, slender, and pointed jaws at its tip. When this structure is
retracted it is invisible, covering the other mouth parts entirely and
hiding them. The term ' ' mask' ' has therefore been applied to it.
Oviposition varies with the species, and is interesting. The
sexes pair during flight. The male has the organs of copula-
tion at the base of the ab-
^^' domen, while the opening

of the testes is at the tip.
Before pairing he fills the
seminal pouch at the base
of the abdomen, then grasps
the female by the neck with
a pair of anal claspers, and
she curves up the tip of
her abdomen into contact
with the opening to the
seminal duct of the male.
As the eggs are fertilized
the pair descend to the
surface of the water, the
female drops a little mass upon the surface, and copulation is
resumed, the process being repeated until all the eggs are laid.

A species of v4^r/o« and its larva; the latter with
anal gill-tufts.

THE INSECT WORLD.

63

In some species the female when impregnated crawls under
water, down the stem of some aquatic plant, and lays her eggs
on stones, plants, or even in the mud. By folding the wings
backward, close to the body, a film of air is gathered which keeps
the insect dry and supplies it with a sufficient amount of oxygen
for a temporary return to its old medium.

The order contains no injurious species, because all are pre-
daceous ; but, on the other hand, none are markedly beneficial,
because, though they devour an enormous number of other
insects, these are not usually species destructive to farm crops.

Order PLECOPTERA.

The ordinal term signifies "plaited wing," and is used because
the hind wings are longitudinally folded or plaited beneath the

Fig. 34.

stone-fly, Perla bicandata. and its larva.

anterior pair, which rest flat upon the back. The insects them-
selves are called "stone-flies," and are loosely jointed, flattened,

64 AN ECONOMIC ENTOMOLOGY.

the thoracic parts large and not closely united, the wings exceed-
ing the abdomen in length. In texture they are rather soft, and
the antennae are long and many-jointed. They frequent the
margins of streams and running ditches, preferring damp, shady
localities. The mouth parts are mandibulate, but their food
habits are not well known. They are not injurious, and are
economically important only as food for fishes. The eggs are
laid in masses upon the surface of the water, through which they
sink to the bottom. The larvae are flattened, live among and
under stones, feeding upon vegetation, and probably also upon
such small, soft-bodied creatures as come in their way. The legs
are well developed and of nearly equal size. The antennae are
long and slender. There are usually slender, hairy appendages
at the end of the abdomen, and on the under side are tufts of gill-
like structures serving for respiration. In some species these
gills persist even in the adult, forming a remarkable exception to
the general rule that adult respiration is through spiracles only.
One natural family the Perlidce, comprises the entire order.

Order PLATYPTERA.

The ordinal term signifies "flat winged," or " broad winged,"
and in those forms in which wings are present the secondaries
are not folded or plaited, but lie flat over the body, covered by
the primaries. The mouth parts are mandibulate, the thoracic
rings are loosely jointed, and as a rule the insects have a flattened
appearance. In most cases the head is large and prominent,
wider than the thoracic rings.

Three distinct families, using that term loosely, are grouped in
this order, diflering greatly from each other, all of some economic
importance, and requiring more detailed consideration.

Family termitid^.
Termites, or "white ants," as they are called, from their
appearance and habits, occur all over the United States, but are
more common southward. They are separated as a distinct
order under the term Isoptera, meaning similar-winged, and are
interesting from their social organization, which is complicated,
several forms or castes existing in each colony. All our species
live in and feed upon woody or fibrous material, though extend-

THE INSECT WORLD.

65

ing their galleries through the soil, often for great distances, and
also inhabiting underground chambers.

In woodland almost any log or decaying tree will be found
swarming with these dirty yellowish-white insects, about one-
fourth of an inch long, readily recognizable by their large heads
and oval, obtusely-
terminated abdomen. Fig. 35.
They are wingless, and
when exposed to light
seek at once to make
their way back into
darkness. These are
workers, and blind ;
they never voluntarily
come out of their gal-
leries, all their wander-
ing being in tunnels of
enormous length run
over or under ground
in every direction from
the main nest. If they
must reach a point
to which they cannot

burrow, they build a covered way of earth mixed with saliva,
woody and excrementitious matter. These workers are the most
familiar to the casual observer, and form much the greater pro-
portion of the inhabitants of a nest or colony. They have distinct,
hard, brown mandibles, not excessive in size, and can be thus
readily distinguished from the soldiers, which are larger, with
proportionately larger heads and very largely developed mandi-
bles. The soldiers form a standing army whose duty it is to
protect the community ; therefore, if we disturb a colony the
workers at once run away, leaving the field to the soldiers, who
are impotent enough in the daylight, blindly gnashing their jaws ;
but are no doubt useful in the ordinary routine of Termite life.
Early in spring we find, in addition, larger, winged individuals,
chestnut-brown in color, and these are the true sexed forms,
male and female. On a bright, warm day, when spring is well
advanced, these individuals, which by the bye are furnished

5

Ttrmes fiavipes. — a, larva; b, winged male; c, worker;
d, soldier: e, female;/", pupa.

66 AN ECONOMIC ENTOMOLOGY.

with eyes, leave the parent-nest in great numbers and fly about,
enjoying for a few brief hours the sun and air. They are then
said to be "swarming," and select their mates, returning to the
surface before the setting of the sun. Out of the vast numbers
leaving the nest few survive the day of flight. They have numer-
ous enemies, and, even if they escape these, must depend upon
being found and adopted by some vagrant workers before they
are able to form a colony. The sexed individuals — king and
queen — are helpless, can do nothing for themselves, and are not
permitted to return to their old home. This serves to keep the
insects in check, for the chances of starting a new colony are
very small. Let us assume, however, that a pair is adopted and
housed, the workers at once building a proper habitation for the
royal pair. Reproduction begins immediately, and the female,
now stripped of wings by her own act, gradually enlarges, the
abdomen ultimately becoming a mere egg-sac. Such a queen
becomes the mother of the colony, and she is tolerably prolific :
sixty eggs a minute have been counted, making a possible output
of over eighty thousand in a single day ! The workers take entire
charge of the eggs and resulting young, feeding and tending
them until they are able to take part in the ordinary work of the
colony. Both males and females are represented among the
larval forms, but it seems to depend entirely upon the nurses as
to what caste is to result. They are able at will to arrest devel-
opment and to produce whatever forms are needed in the com-
munity. Thus workers and soldiers are each of both sexes, but
the sexual organs never become developed or functional. A
certain proportion are allowed to develop fully, and these furnish
the annual swarms. If the queen becomes old or unable to sup-
ply the colony with a sufficient number of young, the workers
provide for a number of " complemental" males and females.
These never become winged, reaching only the pupal stage in
which the wing-pads appear, and they never leave the nest, but
pair within it, the female laying fertile eggs, though never in such
numbers as a perfect queen. Therefore, several of these comple-
mental pairs may inhabit a colony, and there may be no real
queen at all. Curiously enough, no queen of our common species
has ever been found, and we are yet in ignorance of just where
the royal chamber is situated.

THE INSECT WORLD. 67

Termites become injurious in one of two ways : they either eat
into wood-work of furniture and buildings, or they attack grow-
ing plants. In the Northern and Eastern United States they
confine themselves to dead wood, and we have only a single spe-
cies,— Termcs flavipcs ; but in the South and Southwest they
attack living plants, among them orange-trees and sugar-cane.
In buildings they sometimes live in beams, weakening them to
such an extent as to threaten or actu;illy cause collapse. Not
many years ago some of the heavy wooden supports of the Bos-
ton State House were found infested, and more recently a build-
ing in Cleveland, Ohio, was invaded, requiring prompt measures
to prevent accident. They also attack stored products in gen-
eral, skilfully concealing their presence by leaving the outer sur-
face untouched. Thus, in a pile of old records stored in a vault of
the United States Department of Agriculture, a large proportion
was found badly injured, though no external trace appeared. In
the United States National Museum is a mass of black linen
thread from a South American store-house in which the outer
form of a pile of skeins is accurately preserved, while all below
is a mass of hard, black galleries. These are made of the partly
digested and excreted thread itself ; and so we find that in the
galleries in logs or trees the walls are composed of partly digested
wood-fibre.

Termites are often found in decaying stumps, and sometimes
in the roots and stems of weak and dying plants ; in the latter
case often hastening or inducing death. In the Southern States
they are more abundant and troublesome, attacking sugar-cane
and also eating the bark of orange-trees at the crown.

REMEDIAL MEASURES.

Where the insects are found in buildings, injecting bisulphide
of carbon into their galleries will destroy them. They should be
traced to their outside nest, if possible, and, when found, this
should be destroyed. Frequently an old stump of some large
tree may be a centre from which a district becomes infested, and
the bisulphide should be liberally employed wherever the insects
are observed in numbers.

On growing plants the bisulphide is also useful in many in-
stances ; but here, too, the efitbrt should be made to discover the

68

^A' ECONOMIC ENTOMOLOGY.

central colony, rather than to protect individual trees or plants.
Hot water has been recommended, but is not so effective as
the bisulphide. Dead stumps and pardy dead, infested plants
should be removed and burnt, to deprive the insects of congenial
quarters.

The true home of the Termites is in the tropics, where they
are pests of the first magnitude. In Africa some of the species
are mound-builders, erecting turreted structures from ten to fif-
teen feet in height, made up of earth and partly digested wood
and other fibre.

Family psocid^.

To this family belong the minute "book-lice" often found in
dusty corners, under loose paper, in collections, and in other dry
localities. They are always small, resembling somewhat a
"Termite" in miniature, very active, running backward or for-
ward with equal facility, and furnished with very long, slender

antennae or feelers. The head

Fig. 36.

A book-louse, X 25 diameters.

is very large, with small,
coarsely granulated com-
pound eyes. The mouth or-
gans are mandibulate, but
not at all prominent, and
fitted for gnawing rather than
biting, — whence the insects
have been called Corrodentia
or ' ' gnawers. ' ' They are
white or dirty-yellow in color,
and look just enough like
true lice to be mistaken for
them under some circum-
stances. Occasionally con-
ditions favor their increase in
houses, and almost in a day
it will be overrun, beds and

bedding being especially favored, to the horror of the housewife,
who almost invariably mistakes their true character. Several
times within my experience I have received these creatures with
anxious entreaties for a remedy, and equally anxious requests for
secrecy. The Psocids may be always distinguished from para-

THE INSECT WORLD. 69

sites by -their very rapid motions and their long antennae or
feelers. Their food is starch, where they can get it, or dry ani-
mal or vegetable matters, and they can be driven out by a free
use of naphthaline crystals. Their injury in libraries is done by
eating the starched surface of bindings, plates, and pages, and
so disfiguring them.

The forms just described are all wingless throughout their en-
tire life, Atropos [^Clothilla) divinatoria and A. pulsatoria being
common species. In some mysterious way the term "death-
watch" has been applied to these creatures, and they have been
credited with making the ticking sound often heard at night in
old houses, and which is supposed to give warning of a death to
come.

But there are some winged forms, and these somewhat resem-

FiG. 37.

Psociis lineatus, much enlarged.

ble overgrown plant lice, differing, of course, by the mandibulate
mouth. These winged Psocids sometimes occur in great num-
bers on the bark of trees, in my experience most often on cherry
and orange, where they feed upon lichens and other dry vege-
table matter. They sometimes create alarm when great numbers
are noticed by the farmer ; but none of them are in the least in-
jurious. They are more cylindrical in appearance than the wing-
less forms, and the thoracic parts are better developed and larger
than the head, which bears the same coarsely granulated eyes
and long antennae. When a group of specimens is disturbed
they run in every direction, and often drop to the ground
rather than use their wings in flight. Altogether, this family

70

AN ECONOMIC ENTOMOLOGY.

contains insects that simulate injurious forms, while doing little
or no actual damage themselves.

Family mallophagid^.

The literal meaning of this term is "wool eater," and it ap-
propriately expresses the habits of some of the species. All
members of this family are parasitic, and are known as biting
lice ; never sucking blood, but feeding upon young hair, feathers,
skin-scales, clots of blood, and scabby or other scurfy material
found on the skin or among hair and feathers. They infest
warm-blooded animals only, and principally birds, whence the
term "bird-lice" has been erroneously applied to the entire
group. All the common farm animals except the pig are infested

Fig. 38.

Biting-lice.— (I, clog-louse, Trichodectus latus ; b, sheep-louse, Trichodectiis sphcero-
cephaliis ; <-, turkey-louse, Goniodes siylifer.

by some species of this family, and all the poultry or fowls are
troubled to a greater or less extent.

The insects are all small, flattened, with large, prominent head,
often bulging eyes, and short antennae or feelers. The legs are
short and stout, fitted for holding to and moving among hair or
feathers, and the abdomen is oval. No trace of wings is ever
developed.

The eggs are fastened to the hair or feathers of the host, and
in a few days the young emerge, not differing from their parents
except in size and sexual immaturity. The entire life is thus

tup: insect world. 71

passed on the host, and the insects usually spread from one
animal to tlic other on occasions of contact, or through litter
into which some specimens may crawl or be thrown. They also
crawl upon the wood-work of coops and stables, and thence upon
such animals as may rest against it.

The only way to reach these insects is by means of poisons
acting through the respiratory system, and this is not difficult,
because the spiracles are not well protected. Barn-yard fowls
will keep themselves tolerably free if furnished with plenty of fine
dust. The finer it is the more effective, and the birds will so
thoroughly powder themselves that few of the parasites can
escape. Cleanliness on the roosts and in hen-houses is impera-
tive, and a liberal use of whitewash and occasionally of kerosene
on all the wood-work is useful. A badly infected house may be
cleaned by shutting it up tight for twenty-four hours, and evap-
orating in a shallow dish a few ounces of bisulphide of carbon.
This kills all, save eggs, and the treatment should, therefore, be
renewed a week later to reach such as may have hatched since
that previously made. It has also been recommended to hang
small open vials of bisulphide below the perches, and this, it is
asserted, kills the parasites without discommoding the fowls.

On farm animals greasy mixtures may be successfully employed,
or carbolic or tobacco washes or dips. For larger animals —
horses, cows, or mules — a thorough grooming with comb and
brush, dipping the brush into a kerosene emulsion diluted five
times so as to moisten all parts of the body, is decidedly the best
method. This must be duplicated a week later to reach any that
may have hatched from eggs since the previous treatment. On
large herds, badly infested, the kerosene emulsion, diluted nine
times, is simply sprayed on the animals as they pass through a
narrow opening, the application renewed at intervals of a week,
until no more lice appear.

With so considerable a range of remedial and preventive
measures no serious trouble from these parasites need be appre-
hended, and it remains only to urge again the utmost cleanliness
everywhere as the best of all preventive measures.

All the neuropterous orders heretofore treated have had the
metamorphosis incomplete, and are therefore classed as pseudo-

72

AN ECONOMIC ENTOMOLOGY.

or false-neuroptera. While they are not directly followed in the
classification by the true neuropterous series, yet for convenience
they may be so arranged here, and not entirely without reason,
because they are descendants of the same stock.

Order NEUROPTERA.

As this term is now limited it includes only those nerve-
or net-winged forms with complete metamorphosis in which
the biting mouth parts are well developed and not prolonged.
The thoracic parts are large, frequently the prothorax is dis-
tinctly separated and square, and the entire insect is somewhat
flattened.

Of this type are the large forms like Corydalns and Chaicliodes,
and the peculiar Raphidia found on the western coast, members
of the family Sialidce. The head is large and broad, the mandi-
bles well or, as in the male Corydalus, even enormously developed,
the antennae long and many jointed ; in Chauliodes pectinated.
The prothorax is always distinct, square or oblong, in Raphidia
very long and narrow, the other thoracic segments well developed
and loosely held together. The abdomen is soft in texture, and
as a whole the forms appear loosely jointed. The broad wings
lie nearly flat on the back and much exceed the tip of the ab-
domen, the hind pair being partially folded at rest. The eggs
of Corydalns are laid in masses on leaves or sticks, coated with a
water-proof secretion, and from them hatch flattened six-footed
larvae, which live under stones or other shelter on the bottom of
running streams. They are furnished with gill tufts, through
which they obtain oxygen, and prey on whatever insects or larvae
may come within their reach. In turn they are preyed upon by
fishes, and the larvae of the Corydalns cornntns, or "dobson,"
make excellent bait, being locally known as " hellgrammites."
When full-grown they come to the edge of the stream and, under
stones or other shelter, change to quiescent pupae, in which all
of the limbs are free and the form of the future adult is fully
shown.

The species of this family are interesting, but of no sort of
economic importance.

Not so the next family, the Hemerobiidcs ,w\\\ch. contains numer-
ous species of interest, all of them predaceous and beneficial to

THE IXSECT WORLD.
• Fig. 39.

73

The " hellgrammite" or " dobson" in all its stages. — Upper series : a, the larva ; b, the
pupa ; c, the male adult ; (/, the head of the female : in the lower series the leaf bears
egg masses at aa, enlarged at be ; d, the larva just hatched, with details from e toj.

74

AN ECONOMIC ENTOMOLOGY.

the farmer. There are several sub-famUie.s, which together are
termed "lace-winged flies," from their delicate, finely-reticulated
or netted wings, which lie flat and are not folded. The insects
are slight, and in the species allied to Hcmerobiiis the colors are
brownish or smoky. They are less common than the forms
allied to Chrysopa^ which are green, with long antennae and
prominent, bright, yellowish-brown eyes, which have given them
the name "golden-eyed flies" in some localities. They are
commonly found in fields or along the edges of woods, and emit,
when handled, a peculiarly sickening odor which is quite unmis-
takable when once known. In the adult stage the insects feed
little or not at all ; but the larvae, known as " aphis lions," feed
almost constantly, their prey being small, soft-bodied insects of
all kinds, aphids or plant-lice ranking as special favorites.

Fig. 40.

A lace-wiiiged Hy, Ckrysopa oculata. — a, the ejfgs ; b, the larva ; d, same, feeding on a
pear-psylla ; e, cocoon, from which /, the adult, has escaped ; g, head of adult in front,
enlarged.

The entire life history of the insects is interesting. The female
in ovipositing touches the end of the abdomen to the surface, —
usually a leaf, — upon which the eggs are to be laid, and then
elevates her body about a quarter of an inch, emitting at the
same time a viscid thread which hardens on exposure to the air.
At the tip of this the q%% is fastened, and we get thus a little

THE INSECT WORLD.

75

grove ol eggs on stilts. This is supposed to insure their safety
from wandering predaceous forms that might otherwise feed upon
them. Wlien the larva hatches it climbs down the slender
thread, and attacks and feeils upon the hrst suitable specimen it
can find, — usually a young plant-louse. Now, here is another
peculiarity : it does not chew or tear its prey, but holds it firmly,
sucking the juices by means of grooves on the inner side of the
large mandibles, which are closed by the slender maxillae. The
larva grows rapidly, becoming rather more than a quarter of an
inch in length, narrow, spindle-shaped, pointed at the anal ex-
tremity, the head distinct and with prominent sickle-shaped
mandibles. When full-grown it spins, by means of anal glands,
a perfectly spherical, white, silken cocoon of very dense texture,
and small in proportion to the lar\a. It resembles a moderate
sized pearl in form and appearance, and when the adult is ready
to emerge, a circular lid is lifted off to give the matured pupa
exit. Comparing the fully developed insect with the cocoon
from which it issued, the marvel is great that it was ever packed
away in so small a space.

These insects are really of much practical value, frequenting,
as many of them do, tilled fields and orchards, feeding upon
larvae, plant-lice, and similar creatures. They become injurious,
however, in some parts of California, where they attack and
destroy coccinellid or lady-bird larvae.

Somewhat closely allied in all stages to the Hemerobiidcz are
the Myy-melconidcE^ or "ant-lions," but they are larger, with
longer and narrower wings, and clubbed antennae. As before,
the adults are graceful, harmless creatures, which fly mostly at
night, while the larvae are predatory, resembling the "aphis-
lions" in structure, save that they are broader and chunkier in
appearance. They are also peculiar in that many of them
capture their prey in pits or traps.

In constructing its trap, the larva usually selects a spot of mod-
erately compact, fine sand, and excavates a funnel-shaped pit
with the sides as steep as the sand will lie. It remains buried
and invisible in a little gallery at one side of the bottom, in wait
for any unlucky creature that may come within reach. Ants are
the most frequent victims, from their wandering habits and their
tendency to investigate, a pause at the brink resulting in a slip of

76

AN ECONOMIC ENTOMOLOGY.

sand and a tumble into the jaws of the enemy. Should the ant
recover a footing before reaching the bottom, a shower of sand,

sent by the vigilant
Fig. 41. 1 u 1

larva below, over-
whelms and brings
it down to its death.
When the juices
are exhausted, the
empty shell is
thrown out and the
pit is repaired for
other victims.
Sometimes pits are
made in saw-dust
or friable leaf mold
and some make no
pits at all.

The adults are
of two rather dis-
tinct series : the
first with short
antennae which
thicken rather gradually toward the tip, including Myrmeleo ; the
second with long, slender antennae, enlarging suddenly into a
flattened club. The head is larger and the body more robust,
covered with stiff bristly hair, giving the insects a fierce appear-
ance. The most common genus is Asca/aphus, and the larval
habits are not known, though it is probable, from what we learn
of foreign species, that they do not build pits or traps. Though
interesting, the family is of no economic importance.

An odd family is the Mantispidtr, so named from the peculiar
resemblance which they bear to the Orthopterous genus Mantis.
The species are not common, and are easily recognized by the
enormously developed forelegs, which are fitted for grasping, and
are inserted into a long and slender prothorax. They are pre-
daceous, while their larvae are parasitic in the egg-sacs of spiders.
The eggs are laid on stalks, as with the "lace-wings," and the
slender larvae that hatch from them live through the winter with-
out food, becoming active again in spring, when they seek the

Myrmeleo species. — The adult above; the larva in its pit,
which is shown in section.

THE INSECT llOKLD.

77

egg-sacs of Lycosid or running spiders. The larva, that succeeds,
enters the sac and begins feeding upon the eggs, gradually losing
its active form and becoming clumsy and grub-like. The pupa
forms within the larval skin, and after midsummer the adult
appears.

Very curious creatures are the Panorpidcc, or ' ' scorpion-
flies," usually ranked as an order under the term Mccoptera.
They have netted wings similar to but more robust than the
" lace-wings," but have the mouth prolonged into a beak, at the
end of which the biting parts are situated. In the genus Pmi-
orpa the males have a pair of huge anal forceps, curved up some-

FiG. 43.

Manlisf'a species. — Showing the
legs and body from the side.

A Panorpa, or scorpion-fly, and its larva.

what like the sting of a scorpion, and from this the common name
is derived. As a matter of fact, the insects are entirely harmless
save to others of their kind, for they are predaceous. The genus
Bittacus is narrower winged, with unusually long legs, looking
somewhat like a crane-fly at first sight. Species belonging to the
genus Boreus occur on the snow in very early spring. The larvae,
so far as we know them, are predaceous and resemble caterpillars
in appearance ; they have eight pairs of fleshy prolegs, however,
while no true caterpillar ever has more than five. None of the
species are common and none are of practical importance to the
farmer.

The " caddice-flies" have also been elevated to ordinal rank
under the name Trichoptera, or "hairy-winged." The adults
have moderately developed bodies, with large wings, which are
more or less densely clothed with hair, the first pair often thicker

78

AN ECONOMIC ENTOAIOLOGY.

than the second, which are folded beneath them. Both wings
have numerous longitudinal veins connected by only a few cross-
veins, losing the reticulated appearance of the more typical Neu-
roptera, and resembling more closely some of the lower moths,
for which, indeed, some of the smaller forms may be easily mis-
taken. The mouth parts, however, though rudimentary, are
mandibulate in type, and there is no approach to the coiled
tongue of the Lepidoptera. The antennae are very long and
slender, resembling hairs rather than jointed organs.

The species are found frequently in great numbers along the
banks of streams, ponds, or ditches, in which the larval life is
passed. The larvae are caterpillar-like, with three pairs of unusu-
ally well-developed legs, and live in cases which they make of
bits of sticks, moss, leaves, stones, shells, or other material, held
together by silken threads with which the entire inside of the
habitation is lined. Frequently the cases are roughly and irreg-
ularly constructed ; but as often they are marvels of skilled work-
manship. Small
Fig. 44. stones are fitted so

carefully that no
break as large as
a needle-point oc-
curs, and some-
times they mimic
shells so closely
that conchologists
have been deceived
into believing them
such. In these
cases the larvae live,
and from them they
obtain their com-
mon name " caddice " or case-flies. Whatever the form of the
case, the insect lives in and carries it about everywhere through-
out the larval life, crawling about under water by means of the
large legs and keeping the soft, white, hind body constantly pro-
tected. Some live in ponds or sluggish streams, others in rapid
brooks and torrents ; some are vegetarians, some are predatory,
feeding on other larvae or even on small fish. Some forms con-

A caddice-fly, Limnophilus rkombicus, its larva, and at a
the larval case.

THE INSECT WORLD. 79

Struct effective nets in which very young fish become entangled
and fall easy victims to the insect fishermen. Streams in which
these kinds of caddice-flies are abundant are not easily stocked
with fish unless the fry is so well grown as to be out of danger
from this source. Practically, the insects are of no importance
to the agriculturist.

CHAPTER IV.

THE ORTHOPTERA.

Grasshoppers, Crickets, Katydids, etc.

The order Orthoptera, or ' ' straight-winged' ' insects, includes
those forms with biting mouth parts and an incomplete meta-
morphosis, commonly known as "earwigs," "grasshoppers,"
"locusts," "crickets," and "roaches."

The distinctive characters, aside from those just mentioned,
are that the fore-wings are firmer in texture than the secondaries,
and that the latter are folded fan-like, or plaited, when at rest.
They are then covered by the primaries, which are usually nar-
row and of little use in flight, resembling in this respect the wing-
covers of the beetles, and here termed "tegmina." With few
unimportant exceptions the insects belonging to this order are
herbivorous, and among them are some of the most destructive
pests to agriculture, such as the migratory locusts or grasshop-
pers, which have been known and dreaded since the dawn of
history, and the "Rocky Mountain locust," of evil repute in
our own country.

First come the Forficiilidce , or ear-wigs, generally accepted
as forming a separate order under the name Dermaptera (skin-
wing) or Euplexoptera (well-folded wing). They differ from all
the other Orthoptera by having a pair of anal forceps and by
their resemblance to the Staphylinidce, a family of half-winged
beetles. The wing-covers are short and thick, not extending to
the middle of the flattened abdomen, and the large hind wings
are first plaited fan-like around a point near the middle of the
anterior margin, and are then transversely folded into a neat little

8o

AN ECONOMIC ENTOMOLOGY.

packet, which is tucked away under the fore-wings by means of
the anal forceps. Some of the species, however, lack the wings
entirely, in which case the peculiar anal forceps and the beetle-
like form distinguish them quite readily.

Fig. 45.

Cases or caddices, made by the larvae of Trichoptera, illustrating differences of shape
as well as varieties of material used.

Except in the South, ear-wigs are rare in the United States,
and not injurious. In parts of Europe and in sub-tropical and
tropical countries they are sometimes abundant and frequently
annoying, eating at night into flowers in which they hide during
the day. In vine- and flower-covered houses or arbors they are
sometimes a nuisance, and their long, slender form and nocturnal
habits have given rise to the unfounded belief that they crawl
into the ears of sleepers and kill them. The female lays a small
number of eggs only, and broods over or watches them until
some little time after they are hatched.

The more typical Orthoptera may be conveniently divided
into series by their leg structure and method of locomotion, as
follows :

THE INSECT WORLD.

8i

1. The Cursoria, or "'runners," with stout, long legs fitted
for rapid motion, — like the roaches.

2. The Raptoria, or "graspers," in which the forelegs are
developed into grasping organs and the insects are predaceous,
— in strong contrast to all the others of the order.

3. The Ambidatoria, or "walkers," in which the legs are
long and slender, useful for deliberate progress only.

4. The Saltatoria, or "jumpers," which have the hind legs
unusually long and well developed, fitted for leaping, — like grass-
hoppers and crickets.

KiG. 46.

Ear-wig.— I, mature male ; 2, nymph ; 3, the wing, showing the radiate type of pleating.

The Oirsoria, or "runners," belong to the family Blattida,
or roaches. They are flattened, rather soft, repulsive creatures,
with long, powerful, spiny legs ; long, slender, filiform antennae,
and the head bent under the body so as to locate the mouth
parts between the front legs. They are brown or yellow in color,
are nocturnal in habit, and live under bark or in crevices, for
which their flattened form suits them peculiarly well.

Roaches eat almost anything, or are practically omnivorous.
They are among the most ancient type of insects, and are yet
disgustingly common in the tropics, their numbers decreasing
northwardly until only a few cosmopolitan forms are found do-
mesticated in houses.

A peculiar feature in the life history is the method of oviposi-
tion. The eggs mature at about the same time, and are closely
packed into a somewhat bean-shaped case, which the female car-
ries about with her, partially protruding from the end of the ab-
domen, for several days. It is then deposited intact in some

6

82

AN ECONOMIC ENTOMOLOGY.

Fig. 47.

convenient crevice, and very soon thereafter the young issue.
Modifications of this habit occur, and in some cases the eggs act-
ually hatch within the body of the mother,
who thus becomes viviparous.

I am not aware that roaches ever become
injurious to growing crops in our country ;
but two species are certainly great nuisances
in houses, — the " Croton bug," Phyllo-
dromia germanica, and the ' ' black beetle, ' '
Periplaneta orientalis. Both are introduced
and almost cosmopolitan forms. The former
is small, averaging about half an inch in
length, and is winged in both sexes. The
latter is larger, varying between three-
fourths and one and one-fourth inches, with
short wings in the male and mere rudiments
in the female.

The most satisfactory way of dealing with these insects is by
means of a phosphorus paste, spread upon bits of soft bread
and placed near their haunts, all other food particles being care-
fully put out of reach. A short period of such treatment will
usually prove effective. Almost as good is a mixture of equal

Fig. 48.

Forjicula tcsniata,
and female.

male

The Croton bug, Phyllodromia geynnanica. — a, first stage; b, second stage; c, third
stage ; rf, fourth stage ; e, adult ; f, adult female with egg-case ; g, egg-case, enlarged ;
h, adult with wings spread. All natural size except^.

parts of finely powdered chocolate and borax, dusted into the
crevices where the insects hide. The mixture should be inti-
mate, and is best made in a mortar, so that with each part of

THE INSECT JVORLD. 83

chocolate, of which the roaches are very fond, they will get also
a particle of borax, which is poisonous to them. This mixture
has proved successful in many instances within my own experi-
ence, and has the advantage of being cheap as well as non-poi-
sonous to man.

The Raptor ia, or "graspers," form one family, the Mantidcs,
as odd in appearance as their habits are unusual. They are
clumsy, heavy-bodied insects, with short, broad wings, the
middle and hind-legs rather weak, but with an unusually long
and slender prothorax, to which is attached a pair of huge
forelegs, armed with sharp spurs and spines. The head is usu-
ally much broader than the prothorax, with prominent, often
globular eyes, short antennae, and so set as to be capable of lat-
eral motion. It is, in fact, the only type capable of turning its
head !

The insects are, as a rule, sluggish, those occurring with us
incapable of rapid motion, depending entirely upon such prey as

Fig. 49.

The Oriental roach, Periplaneta oricntalis. — a, the male; b, the female; r, egg-case.

comes within easy reach, and securing this through their often
remarkable resemblance to the vegetation among which they
lurk. In other countries there are some more active species,
capable of pursuing and capturing their prey. Their colors are
green or yellowish, like leaves, or brownish, like bark ; the wing-
covers sometimes mottled and roughened to mimic an irregu-
larity or o\ergrown injury on a trunk or branch. Thus con-

84

AN ECONOMIC ENTOMOLOGY.

cealed, they rest, body close to the surface, prothorax elevated,
and forelegs held in the attitude of prayer, whence the term
"praying mantes," Mantis religiosa, which is applied to a for-

FiG. 50.

Stagmomantis Carolina.— a, the female ; b, tlie male.

eign species. But prayer is far from the object in view, as any
small insect that happens within reach learns to its cost. A sud-
den clasp wounds and crushes it into helplessness, and the Mantis
then leisurely devours its victim, the forelegs serving admirably
as hands in the operation.

The eggs are laid in a mass on twigs or branches, held to-
gether by a peculiar silken fibre which encases and protects each
^%^ as well as the entire cluster.

The predaceous habit excludes these insects from the category
of injurious forms ; but they are not sufficiently common in our
country to be of any practical advantage. They are southern in
geographical range, and only one species, Stagmomantis Caro-
lina, is rarely found north of New Jersey on the Atlantic coast.

The Ambulatoria, or "walkers," include a series of very
curious species, popularly known as "walking-sticks" and
"walking-leaves," represented in our fauna by a few species
belonging to the family Phas^uidcs. The true home of these

THE INSECT WORLD.

85

Fig.

forms is in the tropics, where we find excellent examples of pro-
tective mimicry in the development of wings so colored and
veined that the insects cannot be easily distinguished from the
foliage upon which they feed. Our own species have mere rudi-
ments of wings only ; but have very long, slender bodies, an-
tennae, and legs. When at rest, with long legs fully stretched
out, the resemblance to a bare twig or a torn leaf is perfect.

The insects move slowly and awkwardly, feeding on the foliage
of a variety of forest trees, and are occasionally quite destructive.
They do not extend north of the Middle States
on the Atlantic Coast, but occur everywhere in
the Central and Southern States, reaching
northwardly in the Mississippi Valley much
further than in the East. So far as I am aware,
they never attack field or orchard crops, and
are not strictly injurious to agriculture, though
they may be to forestry. Unlike the families
previously mentioned, they take no care of their
eggs, but the females drop them at random upon
the ground. It has been said that in a badly-
infested piece of woodland the pattering of the
eggs as they fall from the trees sounds like rain.

Thoroughly and carefully burning over in-
fested woodland during some favorable period
in winter will prove effective in case remedial
measures become necessary ; spraying with
arsenites can be resorted to for the protection
of single or small groups of trees.

In the Saltatoria, or "junipers," we find the
most destructive species, and they separate
readily into three families : the Acridiidce, or
"short-horned grasshoppers ;" the Locustidce,
or "long-horned grasshoppers" and "katy-
dids ;" and the GryllidiB, or " crickets," which
have long horns or antennae like the Locustidce,
but cylindrical instead of flat, sword-like ovipositors.

The Acridiidce, or short-horned grasshoppers, are among the
most common and best known of our insects, flying up or jump-
ing out of the way, however one turns, among grass or low herb-

Egg masses ol
Stagmoniantis Car-
olina, from above
and from side.

86

ajv economic entomology.

Fig. 52.

Walking-sticks, Diapheromerafenwrata. — a and b, the eggs, enlarged, from the eage
and side; c, young just hatching ; d, the male, and e the female adult.

THE INSECT WORLD.

87

age in roads, fields, or meadows, but not favoring dark woods.
Tiiey have no external ovipositor, but the female is furnished
with four horny valves, between which the eggs pass, and which
are also useful in making the hole, in soil or wood, into which the
eggs are laid. The term "short-horned," as applied to these
insects, is relative, and means that the antenna; are moderately
stout, the joints well marked, and the whole member not as long
as the entire insect, — in fact, rarely even half as long. A curious

Fig. 53.

Rocky Mountain locust ovipositing. — a, a, females with abdomen inserted in the soil ;
b, an egg-pod broken open and lying on the surface ; c, a few scattered eggs ; d, section
of soil removed to show eggs being put in place ; e, an egg-pod completed ; /, an egg-
pod sealed over.

character is a pair of ears situated one on each side of the basal
segment of the abdomen, and we therefore expect and do find
that most of the species are capable of making some kind of
song or noise, though this ability is confined to the male.

A series of species characterized by a very receding front,
meeting the vertex of the head in an acute angle, is referred to
the sub-family TryxalincB, of which there are many species
throughout our country, none of them abundant enough to be
injurious. They are partial to low, sedgy land or meadows, es-
pecially on sandy soil, and I have met with the species most
abundantly near the sea, or on the sandy plains not far inland.
Some species are common on or near cranberry bogs, but are not
injurious.

Quite a series of species is referred to the sub-family CEdipodin(e,

88

AN ECONOMIC ENTOMOLOGY.

Chortophaga viridifascia — a, larva ; b, adult.

and these differ from the preceding in that the front meets the
top of the head in an even, obtuse curve. The species are
usually long-winged, and the thorax is either crested or rough
and tuberculate, with somewhat prominent and sharp angles.
Quite usually the hind wings are brilliantly red or yellow and
black, sometimes blue, and frequently contrasting in color. To
this sub-family belong those species that fly early in spring and

have wintered in
Fig. 55. an immature stage,

ready for the trans-
formation to the
adult form as soon
as the weather per-
mits. Good ex-
amples of such
species are the
green-striped locust {Ckoi'tophaga viridifascia), which occurs
over a large part of the United States, and has the hind wings
without strong contrasts ; and the large, red-winged Hippiscus
discoideiis, which is more southern in its range, not extending
north of New Jersey. Species of this kind are most frequent in
barren, sandy, or partly desert regions, and few ever become
injurious.

Among the troublesome forms are the " Carolina locust," Dis-
sosteria Carolina, and the long-winged locust, Dissosteria longi-
pennis ; the first found throughout the United States, and easily
recognized by its large size and the ample, black, yellow-bordered
hind wings ; the latter a similar but somewhat longer-winged
western species, usually confined to the Rocky Mountain region,
but sometimes migrating for considerable distances from their
normal breeding-places. These species deposit their eggs in the
ground in the fall and the young hatch in the spring.

The "Carolina locust" is often met with in late fall, clinging
fast to the tops of plants, killed by a fungous disease which
ordinarily keeps the species within bounds. It is further con-
spicuous by its habit of poising a few feet from the surface, and
making a continuous " whirring" or rasping sound.

The sub-family Acridiince is one of great extent, containing
those grasshoppers that have become famous by their evil deeds,

Fii;. 5.S.

Fig. 54, Syrbtua adiiiirabilU. ric;. 56, Hippisnts diM-i-idnii. ]-"ig. 57, Vissosfrira
carn/hia. Fig. 5S, Schistocerca americatia. Fig. 59, MiiauDplus sfiretiis. Fig. 60, Mcla-
noplus allanis.

THE INSECT WORLD. 89

and it dififers from the precedint; in havino^ the breast between the
anterior legs produced into an obvious tubercle or pointed pro-
cess. The prothorax is usually smooth and (luitc even, rarely
ridged or crested or even angulated, and the hind wings are not
often contrastingly colored.

The typical genus Acridium of older authors contained the
long-winged forms, which, hatching in great numbers in their
natural haunts, sometimes find food insufficient, and are seized
with a migratory mania that impels them to rise, by what seems
common consent, and fly to fresh fields and pastures new. Such
swarms may number uncounted millions of specimens, and they
leave a wake of devastation which only those who have seen can
appreciate.

The species described in biblical history is the Schistocerca
peregrbuim, or true migratory locust, and is strongly resembled,
except in size, by the Schistocerca americana of the Eastern
United States, which is common and sometimes destructive in the
South, but becomes more rare northwardly, until in Central New
Jersey it is but occasionally seen. In all the species oi Acridium
the wings are longer than the abdomen, and in the males the tip
of the abdomen is not swollen. The sexes in these insects are
easily distinguished, because the female abdomen terminates in
four pointed, horny valves, or pieces, no trace of which is found
in the males.

Perhaps this is a convenient place to describe the life history
of grasshoppers, or Acridiidce, in general. The eggs are most
frequently laid in the ground, though sometimes in partly de-
cayed wood, the horny valves already mentioned serving to
make the holes. The species that oviposit in the ground select
a moderately hard or compact soil where obtainable, not too
densely covered with vegetation, and then force the abdomen
into it as deeply as possible. When this is accomplished the
eggs are laid, each coated with a gummy secretion which causes
it to adhere to its neighbor and to form a pod, extending almost
to the surface. The hole is then closed, and becomes indis-
tinguishable except on close examination. In this state they
remain through the winter, the young hatching during the fol-
lowing spring or early summer. The term nymph rather than
larva is employed for these young, unfledged grasshoppers, and

90 AN ECONOMIC ENTOMOLOGY.

in this stage their traveUing powers are hmited, though their
appetite is not. Yet even now they are able to cover consider-
able distances if a short food supply makes it necessary. The
wing- pads, which become visible early in the nymphal life, increase
in size until the insect is ready for its final change, and when this
occurs its powers for destruction are multiplied by the new facility
in travelling. In some species the wings never become devel-
oped even in the adult ; but these are easily distinguished from
the immature stages of winged forms, because in the latter the
rudiments of the hind wings always cover those of the fore-
wings, while in adults, even when the wings are mere stumps,
the secondaries are always overlaid or covered by the others.

Our best-known migrating forms belong to the genus Melan-
oplus, in which the anal extremity of the males is enlarged and
swollen. Here we find the Melanoplus sprehcs, or ' ' Rocky
Mountain locust, ' ' which in years past has caused ruin in many
States west of the Mississippi, and even yet does much injury
and periodically threatens disaster. The home of this species,
about which volumes have been written, is on the high, dry,
eastern slopes of the Rocky Mountains, and in some regions
west of these mountains in Idaho and Utah. There it breeds
abundantly each year, frequently extending into the adjacent
regions to obtain food and maintaining itself for some time. As
a result of any unusual increase in numbers with a corresponding
failure of food-supply, emigration may become necessary, and the
long, broad wings of the species suffice to carry it even to the
Mississippi River, ranging north and south from Minnesota to
Texas. But in these moist eastern regions the insect cannot
thrive, and from millions of eggs laid only a small proportion of
weakly larvae appear, which usually die before they mature.

An allied but shorter-winged form is the Melanoplus atlanis,
or "lesser locust," which occurs commonly over all the more
northern United States, while the M. fenuir-riibrian, or "red-
legged locust," is much the most common eastern species, some-
times doing considerable injury to crops.

Among the more common short-winged forms we have in the
East species of Paroxya, in which the males are smaller and
ready fliers, the females much larger, with wings covering half
the abdomen, and used rather as aids in leaping than as organs

THE INSECT WORLD.

91

of actual flight. The species of Pezotettix and aUied genera are
short-winged in both sexes, are of medium or small size, and
prefer cool or shady spots on mountain sides, among rocks, at
the edges of woods, or in similar localities, hence never become
economically important. The species are most numerous in the
West and South.

F'iG. 61.

Lubber grasslioppers. — a, Dictyophorus rcticiilatis : b, />'/ iu/iys/o/u iiiagim.

Two very large and clumsy species occur, both known as
"lubbers;" one in Florida, short-winged, yellow and black, is
Dictyophorus retiadatis, — the other, a Western plains species,
dirty-brown in color, and with mere rudiments of wings, also
known as the ' ' Buffalo grasshopper, ' ' is Brachystola viagna.

Last to be mentioned in this series are the "grouse locusts,"
or TettigincB. These remarkable little creatures have the pro-

92

AN ECONOMIC ENTOMOLOGY.

thorax very much developed and extended backward so as to
cover a large part or even all of the abdomen. They frequent
banks of streams and moist places, resembling in color
Fig. 62. j-j^g dead leaves or muddy flats where they often occur,
and they are powerful leapers. Many of the species
are found as adults early in spring, while I have found
others in September. None of them are known to be
injurious.

REMEDIES.

The question of remedies against the ' ' locust, ' ' or

Tettix. short-horned grasshopper, is an important one, not
always easy of solution. As the country is brought
into more complete cultivation the ' ' grasshopper' ' pest will natu-
rally decrease, injury from the migrating forms only remaining to
be dreaded.

In the general life history it was said that a large proportion
of the eggs are laid in fall, remaining unhatched during the
winter. The young nymph, or larva, is a feeble insect, able to
dig to the surface through the way opened by the pod, or through
loose soil, but scarcely otherwise. Fall-plowing the infested land
is therefore a most effective remedy. If the pods are deeply cov-
ered, the young die attempting to get to the surface ; if lightly
covered or exposed, their natural enemies find them easily ; and
when the pods are broken, rain and sunshine induce decay or
disease, and the eggs never hatch. Where grasshoppers other
than the migratory forms are troublesome, systematic fall-plowing
will effect a prompt reduction in their numbers. Special or lim-
ited localities,! like cranberry bogs, are sometimes infested, and in
such cases turkeys are effective. They prefer grasshoppers to
almost any other food, and, if allowed to run where such abound,
will eat nothing else. In some cases the arsenites may be used
to protect crops which are easily sprayed, and occasionally
" driving" will answer for the fledged insects.

Larval forms in grass or short vegetation can be collected in
large pans or "hopper-dozers," drawn by men or horses, and
coated with coal-tar, crude petroleum, or other sticky substance,
and of all these the crude petroleum is to be preferred.

As against the migratory forms in their permanent breeding
grounds, I have no suggestion to make here. The subject has

THE INSECT WORLD.

93

been treated at great length in the reports of the U. S. Entomo-
logical Commission and of the U. S. Department of Agriculture,
and these must be consulted : the methods discussed and recom-
mended are too numerous for reference here. In the invaded
regions foil plowing to destroy the eggs and the use of the
"hopper-dozers" on the young arc indicated.

Under some circumstances, when the number of grasshoppers
is not too great, they may be destroyed, or a large measure of
protection may be secured, by tempting them with poisoned
bran, of which they seem to be rather fond. It should be com-
posed of bran and Paris green, at the rate of one part of Paris
green to fifty by weight of bran, thoroughly moistened with
sugar water. Cabbage patches can often be protected in this
w^ay against grasshoppers that come from uncultivated land, and
there are other cases where such a measure is of value. Indi-
vidual judgment must determine those cases.

The LoaistidcB are "long-horned grasshoppers," "meadow
grasshoppers," and "katydids," distinguished at once by very
long, slender antennae, rarely shorter than, and usually much
exceeding, the body. They are green in color as a rule, with
slender legs and thin wings, and we find them a vast array of mu-
sicians,— always the males only, — the sound-producing structure
occupying a triangular area at the base of the fore-wings, where
they overlap. Here one or more of the
veins is elevated and ridged on each wing,
and by rubbing these ridged surfaces to-
gether a strident sound is produced, in-
tensified by a membrane tightly stretched
between them. The pitch and volume of
the ' ' song' ' are regulated by the develop-
ment of veins and membrane as well as of
the tegmina, no two species being alike in
this respect. Special students of the family
soon learn to recognize the sounds made
by the different species as certainly as or-
nithologists know birds by their song. The
ears through which the songs appeal to the courted females and
competing males are situated on the fore tibiae, and are essentially
like the same organs found on the abdomen of the Acridiida.

Fig. 63.

Overlapping portion of
the base of the wing in Cono-
cephalus ,s\\o\\\t\p, the ridged
veins and sound-producing
organ.

94

AN ECONOMIC ENTOMOLOGY.

Another feature peculiar to this family is the exserted, promi-
nent, blade-like ovipositor of the female, which indicates an es-
sentially lifferent method of oviposition. This, in fact, exists,
for the eggs are mostly laid in plant tissue, — usually in the stems
of reeds and grasses, among which some forms abound, — some-
times in woody tissue ; rarely in leaves, the edges being split to
receive them ; and only occasionally are they laid externally.
Certain cricket-like species are exceptions, and oviposit in the
ground.

The most prominent, from their large size, are the species
loosely termed "katydids," — insects which are familiar by their
song, but are not always personal acquaintances, because they
are most active and noisy in the evening, and prefer trees and
shrubs to more modest plants. The true ' ' katydid' ' is Cyr-
tophylliim concavHJU, much the heaviest in build of all our spe-
cies, with very broad concave wing-covers and an unusually
developed sound-producing structure. In fact, the entire fore-
wings are immense sounding-boards, enabling the insect to make
itself heard at great distances. It produces its characteristic note
three or four times in succession, with slight intervals only, bear-
ing thus a semblance to " Ka-ty-did" or " Ka-ty-did-n't :" oc-
casionally it merely rasps out ' ' Ka-ty. ' '

This species lays its ovate, slightly convex eggs into the twigs
or trunks of trees late in fall, and the young appear during the
early summer following.

One of the most common of the large species, found over a
great part of the Northern United States, is the Microcentruni
retinervis, replaced in the South by the allied M. laurifolium,
which lay their large eggs externally in regular rows on the edges
of leaves, on twigs, or on any sort of likely or unlikely place, —
e.g. , the pulley-strap of a sewing-machine. The Southern spe-
cies is the more common, and in Florida becomes injurious to
young orange-trees by eating the foliage. They can be kept in
check on such trees by collecting and destroying the eggs during
winter, by collecting the insects themselves, or by spraying the
foliage with one of the arsenites.

The genus Scudderia contains smaller, narrower-winged spe-
cies, in which the tegmina are not expanded in the middle and
the ovipositor is curved sharply upward. They frequent shrubs

P'lG. 65.

The Southern katydid, Microcentrum /auri/oliitni. — i, the female adult; la, eggs
laid on leaves and twigs of orange ; lb, the young katydids ; 2 and 2a, female and male
Eitpflmus mirabilis : parasites on the eggs at 2h.

95

96

A.V ECONOMIC ENTOMOLOGY.

and low vegetation, often near marshy or boggy land in sandy
districts. The eggs are sometimes laid in the edges of leaves,
singly, between the upper and under surfaces, and are so 'tKin
that they can be perceived with difficulty only. They swell,
however, very considerably before hatching.

In New Jersey species of this genus sometimes do great injury
on cranberry bogs, eating out the seed-capsule of the berries and
rejecting the pulp. A single specimen may eat, at one meal, the
seed-capsules of five or six berries, and in a week half a peck may
be destroyed or rendered unmarketable.

Turkeys exercise a good effect here also, the insects recog-
nizing the presence of an enemy in a very short time and leaving
the bogs. A good method of lessening the injury is to burn
over the ground around the infested district to destroy the eggs.
Nature itself does much to check increase, the number of speci-
mens averaging about the same from year to year ; so any in-
telligent interference by man must be to his advantage, and a
destruction of the dropped leaves, especially of oak, which may
contain eggs, will be a gain.

Next in size and musical ability are the "cone-nosed grass-
hoppers," Conocephaliis, with very long antennae, very long hind
legs, very long and narrow fore-wings, and a pointed, conically-
projecting head. In the female the ovipositor is as long as or
longer than the rest of the body. These insects may be quite
common, yet rarely seen, because of their resemblance to the
reeds, grasses, and other vegetation among which they live.
They do not become active until late in the afternoon, and may
be located by their loud, shrill, long-sustained song. Then,
quietly waiting until it is resumed, the male may be seen with
wings rapidly vibrating and usually near his mate, for whose
benefit all this concert is produced. The eggs are laid in the
stalks of the reeds and grasses among which the insects live ;
hence late mowing of infested meadows, or burning over, during
the winter, swampy or marshy spots in which they breed will
keep them in check when they become troublesome.

Close relatives of the above are the smaller, green meadow
grasshoppers, largely members of the genera Oi'chelimuni and
Xiphidium, — the former with curved, the latter with a straight
ovipositor in the female. These species all prefer moist lands

V\G. 68.

I'lc. 64.

Fig. 66.

Fig. 67.

Fig. 04. the- katydid, Cyrtopliyllum coiicavum. Fig. 66, Oiclulimum vulgare, male.
Fig. 67, Orchrlmmm vulgare, female, from side. Fig. 68, Mormon cricket, Ancbrui
simplex : a, female ; b, c. anal parts of the male.

THE IXSECT WORLD.

97

with rank vegetation abounding in reedy grasses, in which they
lay their eggs, and among which they sport and sing, except
during midday. They are especially fond of eating the seeds of
grasses, and sometimes become troublesome from this habit.
The late mowing and burning suggested for Conocephahis will
answer in this case as well.

We find quite a departure from the normal type in a series of
wingless or short-winged species erroneously called "crickets,"
and, more correctly, "shield-backed grasshoppers." In the
Eastern United States these are rare, found under stones or rub-
bish in woods, sometimes in caves. Some are blind, and others
have equally interesting structures, but are of little or no economic
importance. From their peculiar humped shape some are known
as "camel crickets." In the West these species become more
abundant, and, at the base of the Rocky Mountains, extending
up into the foot-hills, they find their true home. Here the
' ' Mormon cricket, ' ' Anabnis simplex, occasionally multiplies so
greatly that it migrates to the plains below, destroying everything
in its path. As the insects are wingless they move but slowly,
and may be often checked by ditching in their path. They are
very pugnacious, with cannibalistic tendencies, falling upon and
devouring any injured comrade, and indulging in free fights when
driven into a corner. A plowed field in their course forms a
barrier difficult for them to pass, and in such an army of the
insects can be materially reduced or exterminated by means of
heavy rollers.

Yet more cricket-like are the clumsy, large-headed species of
Stenopalmatus , known on the Pacific Coast, where they occur,
as "sand-crickets." They are sometimes quite plentiful, but
have not been known as injurious, since they are partly carniv-
orous in their food-habit.

The crickets belong to the family Gryllidcr, and differ from the
Lociistid(B in that they have the wings laid flat on the back,
the fore-wings abruptly bent down at the sides, and, in the female,
have the ovipositor cylindrical or needle-like, instead of flattened
or sword-like. This ovipositor usually has a little enlargement,
somewhat resembling a spear-head, just before the tip, which
facilitates placing the ^%'g. The males are even greater musicians
than the Locustidce, the entire wing-covers being modified into a

7

98

AN ECONOMIC ENTOMOLOGY.

stridulating- organ. Here the sound is produced by the ridged
edge of one wing-cover scraping over the ridged veins of the
other, setting into vibration the membraneous spaces in both
wings. The ear is situated on the fore-tibia, as in the LocustidcB.

Fig. 69.

A sand-cricket, Stenopalmatus species.

The mole-crickets are curious, subterranean creatures, with
small heads and powerful forelegs, developed somewhat like the
corresponding organs in the mole. The larger, more common
species belong to the genus Gryllotalpa, and are more frequent

Mole-crickets, Gryllotalpa species.

in the South and Southwest, where they occasionally injure field
crops. They are strictly nocturnal in habit, and remain during
the day in their burrows, in which a chamber is excavated to
contain the eggs.

THE II^SECT WORLD.

99

When they are sufficiently numerous to be troublesome, the
insects may be attracted to the sweetened and poisoned bran
mixture heretofore mentioned, and this will usually check injury.

The field-crickets, species of Grylhts, well known to all, are
found nearly everywhere, even in houses. They are usually dark-
brown or blackish in color, with large, broad heads, and rather
short though power-
ful hind legs. They ^''^''- '2
are very active, and
jump about so errat
ically that it is not u | a

Fig

A field-cricket, Gryllm
species.

The tree-cricket, fif<rt«////(i iiiveui, female from
the side, male from above.— a, blackberry cane
showing egg punctures; b, the same, split, to
show the arrangement of the eggs ; c, egg, very
much enlarged ; d, its tip, yet more enlarged.

always an easy task to capture the specimens. There is less
trouble in the fall, when the female is ovipositing in warm, sandy
spots, and the male is watching her, keeping up a constant sing-
ing during the operation. As a rule the species winter in the &gg
state, but occasionally nymphs and adults survive, and a solitary
and melancholy chirp in spring now and then tells of such a speci-
men. Most of the species are plant-feeders, yet rarely attack

loo AN ECONOMIC ENTOMOLOGY.

green vegetation ; fruits like cranberries are occasionally eaten
into, and sometimes roots or tubers are attacked ; but the injury-
is rarely of economic importance.

Crickets are pugnacious as a rule, occasionally eating their
companions, or such other soft-bodied specimens as fall in their
way, while "cricket-fights" are not unknown in the lists of sports.

The tree-crickets, CEcanthus, are more slender and graceful
than any of the preceding, and more ready fliers. They are
green, yellowish, or gray in color, and live on trees or shrubs,
feeding chiefly upon plant-lice and other soft-bodied insects of
various kinds. They lay their eggs in the stems of pithy plants
like blackberry and raspberry, puncturing the wood by means of
their powerful, auger-like ovipositor. Quite often these punctured
canes die, but practically little damage is done unless the insects
are much more abundant than I have ever seen them. In either
blackberry or raspberry canes the punctures are so readily seen,
especially in spring, that they can be cut out while trimming and
the whole brood destroyed. This is indeed the best method of
dealing with these graceful creatures, who have little resemblance,
except in essential structure, to their lowly and sordid cousins of
the field.

CHAPTER V.

THE HEMIPTERA, OR BUGS.

The term Hemiptcra means half-winged, and is primarily ap-
plied to insects in which the wing-covers are partly thick and
leathery and partly thin and membraneous, the latter texture
obtaining towards the apex. The term becomes inapplicable,
however, in those insects which, agreeing otherwise in structure
with the half-winged species, have the anterior wings of the same
texture throughout, whether like that of the hind wings or de-
cidedly thicker. To distinguish the two series the terms Heter-
optera, meaning "different wing," and Homoptera, meaning
"equal wing," are applied. Besides these there is another
division which has no wings at all, and, owing to the fact that

THE INSECT WORLD. lOi

the species live and feed upon animals, .this is called Parasitica.
All these agree, however, in the essential character of the order,
which is found in the structure of the mouth parts. Throughout
all series we find the head prolonged into a jointed beak or ros-
trum, obsolete only in the Parasitica, and within, protected by
it, is a series of three or four slender, needle-Hke lancets. The
beak is open in front, and the lancets may be protruded at the
tip. In most species, when the insect is feeding, the lancets are
so deeply inserted that the beak bends at or about the middle,
leaving them entirely free except at the tip. In other cases,
among predaceous types, the beak is too rigid to bend thus, and
it, as well as the lancets, is forced into the tissues upon which
the insect feeds. It is to insects of this order only that the ento-
mologist applies the term ''bug''' and when he uses that word
he always refers to one of the Hemiptera. It has been indicated
that the creatures gain their food by piercing and sucking, and
this is a radically different method from anything found hereto-
fore. We have now insects that are incapable of chewing food,
and subsist only upon liquids which must be drawn from living
tissue, be it animal or vegetable. A large proportion of the spe-.
cies is injurious ; but there are also groups of predaceous habit,
feeding upon other insects in whole or in part, that may be con-
sidered beneficial. In their development the insects belong to
that series in which the metamorphosis is incomplete ; but there
is an exception in the males of certain bark-lice, where there is a
real, quiescent pupal stage.

Before going further on this subject it is necessary to refer to
the peculiar little species known as Thrips, and belonging to the
family Thripidce. They are now as a rule, and properly, sepa-
rated from the true Hemiptera under the ordinal terms Thysan-
optera, meaning fringe-winged, or Physopoda, meaning bladder-
footed. They are always small in size, slender, active, with the
head so narrow that they seem pointed at both ends. The wings
are laid longitudinally on the back, and are very narrow, trans-
parent, without veins or with mere rudiments, but with lengthy
fringes, which give them a characteristic and peculiar appearance.
The feet are not terminated by pointed claws as usual, but by
small, bladder-like dilations of the terminal joints. They run
and fly readily, and some of them jump much as do spring-tails.

AN ECONOMIC ENTOMOLOGY.

Fig

Thrips tritici. — b, antenna ; c, a tarsus.

The mouth structure is in some respects intermediate between
that of the true bugs, as already described, and that of the man-

dibulate type ; but there are no
true mandibles, and the insects can-
not chew their food, hence come
naturally, for our purpose, into this
order.

The species of Thrips are often
seriously injurious to vegetation.
They sometimes attack onions in
great numbers, puncturing the suc-
culent leaves, and everywhere leav-
ing a small yellow dot. As these
increase in number the leaf loses
vitality, the top itself turns yellow,
and in serious cases the rich green
of a normal onion field is changed
to a peculiar, sickly yellow. The
insect is yellowish when immature, and blackish-brown when the
wings are developed.

Cabbages sometimes suffer in a similar manner. The insects
in this case are yellow, and congregate in large numbers on the
lower side of the outer leaves, and as these become dry and
wither they move to those nearer the centre.

Grass is often attacked by them, and here they cause one
form of what is known as ' ' silver top. ' ' Wheat, oats, rye, and
other grains are often victimized, and, indeed, there are few
plants not liable to infestation, even tobacco appearing among
the sufferers.

These insects thrive best in hot, dry weather, hence become
more dangerous as the plants are less able to resist them, and
our effort must be in the direction of aiding the crop as well as
destroying the insects. Contact poisons are indicated here, as
against the true Hemiptera, and either the kerosene emulsion,
diluted ten times, or the whale-oil soap, one pound in four gal-
lons of water, is satisfactory. Plenty of cold water, where it is
available, acts very well on a small scale ; but no application is
feasible on large fields of cereals or grass. Here stimulation only
can be resorted to to give the plants additional vigor, and har-

THE INSECT WORLD. 103

vesting should be done as soon as possible to check the increase
of the pests.

Many species of Thrips are found on flowers, many also under
the bark of trees, and some forms are said to be predaceous.
Their life habits are not well known, but a large number winter
in the adult stage under such shelter as they can find, — hence,
cleanliness on the farm is indicated.

For a better understanding of the characters of the more typi-
cal Hemjptera, we will take up the families separately ; and first
the Parasitica. By taking up this series before the others it is
not to be understood that they are higher in the scale, nor, on
the other hand, much lower in type ; but it is simply a matter
of convenience. Parasites, because of their habits, are often said
to be ' * low ;' ' but it is a question whether this is true, because
parasitism is an acquired character, and the insects are really
much specialized for their habit of life and well adapted to it.
We have in a previous chapter considered the biting lice, and
found that they feed more particularly upon surface structures.
The sucking lice, as the term indicates, obtain their food by
piercing the skin and sucking the animal juices or blood. The
mouth differs from that of the other bugs in that the proboscis
is fleshy and unjointed, capable of being withdrawn into the head
or extended, and within it are two protrusible lancets only. At
its base is a circlet of hooks, by means of which the insect an-
chors itself firmly in the skin of the infested animal. The legs
are "scansorial," or fitted for climbing, — that is to say, they are
short, heavy, set at the sides of the thorax, and the tarsus is
modified into a stout, slightly curved claw, opposed like a thumb
to the end of the tibia, which in turn is broadened at the tip and
a little excavated. Thus, between the end of the tibia and the
tarsus, the insect is able to grasp a hair so tightly that it is some-
times easier to pull it from the skin than to dislodge the parasite.
Here we have another example of insects that do not change in
appearance throughout their life : they simply increase in size
and become adult when the sexual organs are fully developed.
Warm-blooded animals only are infested by these sucking lice,
man being included under this general term.

Three species are found on the human animal: one, Pediculus
capitis, infesting the head, glues its eggs, which are known as

I04

AN ECONOMIC ENTOMOLOGY.
¥\G. 74.

Hog-louse, Hcematopinits urius : the scansorial claw at c.

Fig. 75.

Ox-louse, HcFtnatopinns eurystemus : b, mouth opening ; c, d, anal details ; ^, egg
attached to a hair.

THE INSECT WORLD.

105

"nits," to the hair; one, Pediculus vestivicnti, found on the
body, knt)\vii as the "body-louse," or to soldiers as "gray-
backs," lives in and lays its eggs in the seams of clothing, where
they are protected ; the last, Phthirins inguinalis, known as the
"crab-louse," infests the pubic region and armpits. The latter
fastens its eggs to the hair among which it lives, and this is per-
haps the general rule throughout the series.

Domestic animals of all kinds are infested by lice ; but it is not
necessary to study the species in detail, since their habits are
much the same, and the method of treatment is identical. For
the head-louse on man nothing is better than a thorough appli-
cation of lard, vaseline, or other greasy material. It should be
applied at least twice at intervals of a few days, because the treat-
ment does not kill eggs, and eggs unhatched at the first treat-
ment would not be affected.

As against the body-louse, the application of mercurial oint-
ment in the seams of the clothing answers every purpose. This
has proved effective in camps and hospitals, where the insects
sometimes increase with marvellous rapidity.

As against the "crab-louse," the mercurial ointment may be
applied directly to the infested spots, and here also several ap-
plications are necessary to reach
the insects as they hatch from the Fu;. 76.

eggs. Their vitality is great, and
that of the eggs is yet greater.
Clothing, no matter how carefully
washed, may still remain infested
with eggs, protected as they are
in the seams, unless actual boiling
is continued for a considerable
period of time. Where lice infest
animals the latter can sometimes
be cleared by simply giving them crab-iouse, Phthh-ii.s in^mnaiis.
an opportunity to dust themselves.

Dogs, donkeys, less frequently horses, and other animals, may
be often seen in dusty roads, rolling about in evident enjoyment,
and one result of this powdering is a comparative freedom from
insect parasites for some time thereafter. Infested animals may
be treated as suggested for the head-lice in man,— that is, some

lo6 AN ECONOMIC ENTOMOLOGY.

heavy oil or grease should be applied thoroughly. It will add
to the effect of the mixture if a little carbolic acid is added, but
it is not essential, though desirable to prevent rancidity if animal
fat is used. The kerosene emulsion, used with a brush or curry-
comb in cleaning animals, is also effective ; in fact, the treatment
suggested for the biting lice is also applicable here.

The section Homoptera contains scale-insects, bark-lice, mealy
bugs, plant-lice, tree-hoppers, leaf-hoppers, frog-hoppers, and
others whose very names proclaim their character. Nowhere do
we find predaceous forms, or such as can be accounted beneficial
to the agriculturist. To be sure, we have among the Coccids the
cochineal and lac insects, but these are fully as injurious as any
other to plant life, and are useful simply because man is able to
make better use of them than of the plants upon which they feed.

The family Coccidce includes scale-insects and mealy bugs, cu-
rious in their life history as well as injurious to cultivated plants.
The males, unlike other Hemiptera, have a complete metamor-
phosis and only a single pair of wings, the secondaries disap-
pearing or reduced to mere hooks. They are singular, fur-
thermore, in that the mouth parts are replaced in the adult stage
by a pair of eyes. The female is always wingless throughout her
entire life, generally grub-like and stationary, covered with some
sort of waxy scale or by a powdery or cottony secretion.

Mealy bugs derive their name from the fact that they are cov-
ered by a white, powdery substance, which is really a granulated
wax and a secretion of the insects themselves. They move about
freely, and are furnished with all sorts of odd processes at the
sides of the body, or with long filaments at the end. They are
not usually common in the North except in greenhouses and on
in-door plants, but become more abundant southward, where out-
door plants are also infested, orange-trees in Florida being par-
ticularly troubled. To this series of mealy bugs the cochineal
insect, Cocciis cacti, belongs. It is a native of Mexico, but has
been cultivated in other countries, feeding upon species of cac-
tus. Specimens have been found in Florida, and it is more than
likely that it occurs not uncommonly in the semitropical part of
the peninsula. It also occurs in California. The dye is simply
the immature female insect, which is brushed off the plants,
killed, and dried, and has never been equalled for brilliancy and

THE LWSECT WORLD.
Fig. 77.

107

Fig. 7S.

Fig. 79.

Cochineal and mealy bugs. — Fig. 77, cochineal, Coccus cacti, on cactus. Fig. 78,
b, adult male; c, adult female, with cottony masses removed. Fig. 79, mealy bug,
Dactylopius destructor. Fig. 80, Dactylopius longifilis : a, the larva ; b. the winged male.

Io8 AN ECONOMIC ENTOMOLOGY.

permanence. Aniline dyes and colors are superseding it, how-
ever, because of their cheapness and the greater ease with which
they may be obtained.

Mealy bugs are easily destroyed by contact poisons, almost
any soapy solution killing them readily. A very dilute kerosene
emulsion answers every purpose, and even a weak salty solution
is satisfactory. I have used both kainit and muriate of potash
dissolved in water at the rate of an ounce in a quart, and it has
been perfectly effective where entire plants have been dipped into
it. A tobacco decoction, one pound in one gallon of water, is
also useful, and not dangerous to the most delicate plants. Where
house-plants are troubled the tobacco water is very convenient,
or common insect-powder may be used at the rate of an ounce
in two quarts of water, and sprayed on with an atomizer. Where
applications are to be made on a large scale, the diluted kerosene
emulsion is the most satisfactory, one part in fifteen of water be-
ing ordinarily sufficient.

Next comes a series where the excretions are in the form ot
waxy scales, which sometimes become hard, brittle, and beauti-
fully ribbed. The female forms a sort of sac of these waxy scales,
and in it the eggs, mixed with a very fine powder, are contained.
This type is also rather more common southwardly or in warm
countries, the few species that occur in the North being rather
scarce and generally confined to weeds. The " cottony cushion
scale," Icerya purchasi, which has caused such injury in Cali-
fornia, belongs here, and we have several allied species in Florida,
and yet more in the West Indies. All these insects gain their
food by sucking the plant juices, and their power of injury is
magnified by their enormous productiveness.

Perhaps this is a good place to speak somewhat at length on
this " cottony cushion scale," and the measures taken against it
by introducing foreign predaceous species. The very remarkable
success that has attended the introduction of "lady-birds"
(Coccinellidae) from Australia has led many persons to the belief
that insects of similar character might be introduced from other
countries to deal with some of our native species, and much
time has been wasted and some money spent by ill-considered
schemes of this description. The factors that caused success in
the case of the Icerya were : ist, an insect introduced from a

THE INSECT WORLD.

109

foreign country where it was on the whole rather scarce and kept
in check by natural enemies ; 2d, its introduction into America,
where these natural enemies did not exist, and where the insect
found favorable opportunity for multiplying ; 3d, the introduction
of some of its foreign parasites and of the predaceous insects

feeding upon the species ; lastly, and most important of all, the
Australian lady-bird recognized no other insect among those
found in California as proper food, and naturally confined itself
entirely to these scales. The contest was unequal, and the scales
lost rapidly, soon becoming nearly or quite exterminated. The

AN ECONOMIC ENTOMOLOGY.

Fig

chances are now that the lady-birds will follow them and become
scarce or extinct, unless they show the power of adapting them-
selves to surroundings, and
find other food to their liking ;
but while they have been use-
ful as against the Icerya, and
may have entirely destroyed
it, we cannot hope that they
will be equally successful in
coping with our native insects,
who have long since adapted
themselves to their surround-
ings in such a way as to make
it unlikely that any intro-
duced species will be effectual
in seriously lessening their
numbers. Insects of this char-
acter are susceptible of treat-
ment with the kerosene emul-
sion, although, where they
occur in such numbers as did
the Icerya in California, this
treatment becomes exceedingly expensive and practically useless.
A curious series of species is found in the genus Kermes, often
found on oaks, and resembling at first sight galls or even small
snail-shells, their texture being almost as brittle as if composed
of lime. They are never economically important, but curious
enough to deserve mention here.

Next come what are known as "soft scales," usually of con-
siderable size and readily visible. Quite commonly they are
convex or nearly hemispherical, rarely quite regular in outline,
and sometimes ribbed or ridged. In most instances they are
brown in color, not very rigid in texture, and easily crushed ;
whence the term " soft scales." We have a number of injurious
species, and perhaps none more common than the ' ' cottony
maple scale, ' ' Pidvinaria innumerabilis . Though called the viaple
scale, and found most frequently on that tree, yet it is by no
means rare on grape, and often common on the Virginia creeper.
Sometimes it occurs on other plants as well, and is occasionally

Icerya purchasi, female.

THE INSECT WORLD.

Ill

numerous enough to require treatment. It usually attracts atten-
tion in spring, when white cottony masses become numerous on
twigs or leaves, increasing in size until they are one-fourth of
an inch or more

in length, and only Fic. 83.

slightly less in diam-
eter, though irregu-
lar in outline. The
mass seems cottony,
but is actually a wax
or gum, for, if a bit
is taken with a for-
ceps it can be drawn
out into strings of
considerable length.
When of this size it
forms a bedding for
innumerable, rusty-
brown, minute eggs,
which have been
laid by the female
insect under the
brown scale which
seems to form the
head of the mass at-

Cottony maple scale, Pulvinaria inniimerabilis, showing, at
a, the female on a leaf and, at b, same on a twig.

tached to the twig.

From these eggs minute, crawling larvae hatch, much like the
, eggs in color, and which separate in every direction in what seems
to be a moving mass of fine dust particles. In a day or two each
larva inserts its beak into a leaf or twig, and commences the for-
mation of a little, flattened, oval, somewhat mottled scale. They
remain thus, feeding and increasing in size, and as they increase
the scales enlarge. The males come to maturity in the latter part
of the summer, appearing as minute, two-winged flies, furnished
with long anal filaments. They mate with the females which re-
main under the scale, and these, before the leaves fall, migrate to
the twigs or branches, where they fasten themselves to pass the
winter. Feeding is resumed in spring, when the sap begins to
circulate, and then the ^g'g masses begin to form. Before the

112 AN ECONOMIC ENTOMOLOGY.

cottony secretion becomes visible the female scale is less than
one-eighth of an inch in length, very convex, a little irregular,
and mahogany-brown in color. As the Q^g<g mass increases in
size the scale is lifted posteriorly, until finally the insect adheres
only by its beak and by the sticky nature of the cottony mass.

Fig

Cottony maple scale. — a, leaf covered with scales; b, male scale; c, adult male.

We have other species of similar character in which there is
no cottony mass protecting the eggs, but the life history is essen-
tially the same. These ' ' soft scales' ' mostly belong to the genus
Lecanmm, and are much more common southwardly and in con-
servatories. Citrus fruits and olives are especially subject to
soft-scale attack, and the "black scale," Leca^ihan olea, is in
California the most troublesome of all and the most injurious.
In the genus Ceroplastes the scale is formed of waxy layers,
sometimes quite pretty in pattern. These are found only in the
extreme South, and are not especially troublesome.

The matter of remedies will depend entirely upon circumstances.
On garden plants or shrubs the scales may be mechanically
removed during the winter. They do not adhere closely, are
easily dislodged, and are of a size sufficient to be readily seen.
Not all, however, pass the winter in the adult condition. In some

THE INSECT WORLD.

"3

cases, instead of a female, an egg mass will be found beneath the
scale ; but in either case mechanical dislodging results in the de-
struction of the insects.
Very often a little judicious '

pruning or trimming, done
during the winter, will give
relief, because the insects
usually settle on the termi-
nal twigs, and it might
easily be that none of the
larger branches contained
living scales or eggs. In
conservatories the mechan-
ical method is, all things
considered, the best. It
may take a little more time,
but it is thoroughly effect-
ive, and when carefully
done there may be almost
total exemption until scales
are again introduced with
new plants.

This is a good place to
say that no plant should be
placed in a garden or con-
servatory until it has been
thoroughly cleaned of all
scales found on twig or fo-
liage, and a soft tooth- or

hand-brush, with moderately strong soapsuds, forms a good outfit
for doing the work. Where winter treatment is inadvisable or
impossible, applications should be made when the larvae emerge
from the eggs and before they fasten themselves to leaves or
twigs. There is no difficulty in killing the young with either
soapsuds or kerosene emulsion, but — ^and here is the important
point — the application must be made before the insect is pro-
tected by a scale, or when the scale is yet very thin and newly-
formed. Kerosene will penetrate the waxy mass of the maple
scale, but it will not certainly kill the eggs contained in it ; yet

Lecanium hemisphericum, on orange-leaves, nat-
ural size ; a, female scale, enlarged.

114

AN ECONOMIC ENTOMOLOGY.

if soapsuds be used to dilute the emulsion, instead of water, the
cottony mass will be so impregnated with soap, and become so
compact, that the young will be unable to make their way out.
Therefore, in this case, dilute three quarts of kerosene emulsion
with one pound of whale-oil soap dissolved in eight gallons of
water.

The most troublesome of all scale insects belong to the Dia-
spince, or * ' armored scales, ' ' and these are generally small in
size. They are, as a rule, only a little convex, occasionally even
flattened, and in texture are more like membrane or parchment
than wax. All kinds of shapes occur, and there is considerable
variation in life history. In one point they all agree, — after the
active larvae have once become fixed and covered with a scale,
they never leave their position, except when the males emerge
as adults and visit the surrounding females. In general the life
history of the insects is as follows : the larvae, whether hatched
from the eggs or born alive, crawl about for a few hours, or at
most a day or two, seeking a convenient place to fix. They are
always minute, flattened, oval creatures, with six legs, a pair of
distinct feelers, and a curious, long, sucking mouth. This is
soon inserted into the plant tissue, and from that time the insect
is a fixture. Little waxy filaments begin to exude from the body,
which soon coalesce, or run together, forming a first covering or
scale over the soft larva. The insect soon moults, and the cast
skin forms part of the scale, the resulting creature being legless
and without power of motion. There is one additional moult,
after which the sexes are very different in appearance. The male
shows antennae, legs, and wings well marked, and is indeed a
perfect pupa, while the female is even more grub-like than before,
rudiments of antennae only being visible. The second cast skin
of the female also forms a part of her scale, and there is nearly
always some difference in shape between the sexes, the male
being not only smaller, but narrower. Shortly after the change
to the pupa the male becomes adult, and in this series has the
end of the abdomen prolonged into a style or pointed process,
sometimes equalling in length the rest of the insect, though
usually shorter. Antennae and wings are both prominent, and
as a whole the insect is curious and exceedingly fragile in appear-
ance. Its life is probably short, though long enough to accom-

THE INSECT WORLD.

"5

plish its mission, — the fertilization of the female. After this the
life histories differ greatly ; sometimes the female lives through
the winter in the partly-grown or adult condition ; sometimes she
lays eggs which fill up the entire space beneath the scale, the
insect itself shrivelling up until scarcely a trace remains. Some-
times living young are brought forth, and there may be one or
several broods. Hence it is necessary to study each species in
detail before we can say much on the subject of remedies. It is
obviously beyond the province of this book to describe all the
injurious species, and general statements only are possible.

Fig. 86.

Oyster-shell scale, M\tila'if<is pomoriDii. — a, female scale, from beneath, filled with
eggs ; b, same, from above ; c, twig infested by female scales ; d, male scale and a twig
infested therewith.

Perhaps the most common forms of this series are the ' ' oyster-
shell' ' bark-lice, of which we have several species, deriving their
common name from the fact that the scales have a marked resem-
blance to the shells of some oysters. In the Northern United
States Mytilaspis pomorum is the common form, infesting apple

ii6

AN ECONOMIC ENTOMOLOGY.

and other fruit trees, willow, lilac, and a great variety of other
plants. It is perhaps uncertain whether all are really one species,
but for our present purpose we may consider them so. There is
one brood only, and they winter in the &^% state, the larvae
appearing in spring, the time depending upon the weather. In
the South there may be two broods, but I believe that there are
few exceptions to the rule that wintering takes place in the ^^^
stage. On orange and other citrus plants we have species closely
resembling that on the apple, and not distinguishable except on

Fig. 87.

Mytilaspis pomorum.—a, male ; b, its tarsus ; c, young larva ; rf, its antenna ; c, female.

close examination, even by the specialist. These scales some-
times cover twigs and large branches completely ; even the leaves
are often infested, and not infrequently the fruit itself becomes
more or less covered. It is not unusual to see in market oranges
and lemons more or less spotted by these oyster-shell scales, and
I have seen lemons from Mediterranean countries with the skin
almost entirely hidden by them.

THE IXSECT WORLD.
Fig. 88.

117

-^^^^^EEQCT

The San Jose scale : winded male above ; a, young larva, just hatched ; b, its antenna ;
c, female, showing the forming young through the body wall ; d, outline of anal plate
of female : all very much enlarged.

Ii8 AN ECONOMIC ENTOMOLOGY.

In our treatment of these insects we must either apply exceed-
ingly caustic winter washes, to corrode the scale and allow the
eggs to be washed out by rain or destroyed by other climatic
influences, or we must apply contact insecticides when the eggs
hatch or the larvae emerge from beneath the scales.

Some of our destructive species belong to the genus Aspidiotus,
and these have the scale nearly circular in outline, with the rem-
nants of the cast larval skins showing through at or near the
middle and forming a sort of nipple-like prominence. The male
scales are decidedly smaller than those of the female, and some-
what more oval or oblong. The ' ' red scales' ' of the orange in
California and in Florida belong to this genus ; but perhaps the
most troublesome of all is the A. per^iiciosus , or San Jos^ scale.
As this species is now widely distributed and very injurious where
it occurs, its life history may be given in some detail.

The insect winters on the infested trees in the larval state, and
usually about half grown, both sexes being found. Males mature
soon after spring opens, — in the latitude of Philadelphia, about
the end of May, but depending somewhat upon the season.
On or about the loth of June the females become fully devel-
oped, and begin to bring forth living young. That is to say, the
species is viviparous, and produces no eggs. The larvae do not
differ essentially from those of other scales, and fix in from twelve
to thirty-six hours, depending somewhat upon circumstances.
At that time a thin white pellicle forms, which soon turns yellow,
and a little later becomes gray around the edges. The insect is
then a fixture, and continues its growth much as previously
described, but reaches the adult condition, and is ready to repro-
duce, in a little more than a month. This short period enables
it to mature several broods, and during the entire summer, and
until late fall, reproduction continues, — the broods becoming
mixed, and all stages being present continuously upon the plants
soon after summer opens. With such a life history the insect is
exceedingly difihcult to control, and practically we are reduced to
winter work, as will be hereafter pointed out. The scale infests
all the usual deciduous fruit-trees, roses, currants, gooseberries,
— in fact the entire order Rosacece, and occasionally occurs on
chestnut, walnut, and elm. It is probable that yet other plants
are subject to infestation, and this omnivorous habit and the

THE INSECT WORLD.

119

\

wonderful power of reproduction make the scale especially dan-
gerous.

In the genus Diaspis tiie scales are more oval, and the cast
larval skins are at or near the margin rather than toward the
middle, while the

males are long and Fig. 89.

slender. A common
example is the Di-
aspis rosa;, found
on roses and other
plants belonging to
the same natural
family. The scale
is pure white and
very conspicuous,
measuring nearly an
eighth of an inch in
diameter.

Yet more oval,
with the cast larval
skins at the smaller
extremity, are spe-
cies of Chioiiaspis,
and a good exam-
ple is the ' ' scurfy
scale, ' ' C. furfu-
rus, common on
pear and apple. A
similar species is
found on pine and
spruce throughout

the United States. These species may have one or two gener-
ations, according to latitudes, but ususally winter in the egg state.

Some of the species have the curious habit of boring under
bark, thus passing a large part of their life out of sight, becoming
more dangerous by that fact, since trees may be badly infested
and the cause of sickness not even suspected by the farmer.

It is practically impossible to even mention all the injurious
scales of house, conservatory, or orchard plants, and it is not

/

CL

San Jose scale on a California pear, natural size ; the scale
itself enlarged at b.

AN ECONOMIC ENTOMOLOGY.

really necessary, since the treatment to be adopted is nearly the
same in all cases. On deciduous trees, where the scales remain
during the winter upon trunks and branches, and where the trees
become dormant, the scales are best treated during the winter.
At that time there is no foliage to interfere, and we can use much
stronger washes than would be safe during the summer, or when
the tree is active. I have already called attention to the fact that
it is difficult to penetrate insect tissues with ordinary liquids, and
it has been found impossible in practice to obtain good results in
the destruction of scale insects except by means of caustics.

Potash and soda have
Fig. 90. been used with good effect

even in a simple watery
mixture, but more satis-
factorily in the form of
very caustic soap. Whale,
or other fish-oil soap, at
the rate of two pounds in
one gallon of water, as a
winter wash, has proved
absolutely effective against
the San Jos6 scale and the
oyster-shell bark-louse,
two of the most resistant
of the armored scales.
The simple muriate of
potash used as a fertil-
izer has proved effective
against the scurfy scale, while common laundry soap has been
efficient against others of the softer species. The common soaps
are all caustic, and, when applied at the strength indicated, the
scale is shrivelled, lifted, and partially corroded, so that the oily
mixture works its way beneath, into absolute contact with the
insect. Or it is raised at the edges and washed off by the rains,
carrying with it either eggs or young, as the case may be. In
fact, where the eggs hibernate winter applications act only by
exposing them, so that they are easily washed away by rains and
scattered, under no proper condition to hatch. Or, should they
hatch, the larvae are able in rare instances only to get upon the

3

The scurfy scale, Chionaspis furfurus. — a, twig
infested by female scales ; b, with male scales ; c,
female ; d, male scale, much enlarged.

THE INSECT WORLD. 121

proper food-plant. In the case of plants which do not lose their
foliage at any period, or in conservatories, or where winter treat-
ment for any reason is not feasible, we must attack the insects
when the larvae are crawling about, and before they are fixed.
At that time, while not protected by a scale, they may be easily
killed, almost any of the contact insecticides being effective.
Soapsuds, a dilute kerosene emulsion, or a mixture of both, are
satisfactory, and a good formula is : kerosene emulsion one part,
soapsuds ten parts, the suds being of the strength of one pound
of soap to six gallons of water. Whale or other fish-oil soap is
better than common laundry soap, and the latter is better than
high-grade articles containing only a minimum amount of caustic.
This would not hurt any except very delicate plants, while it
would be absolute death to larval scales. It is useful in the con-
servatory on palms, which are often much infested, and for some
of these it might be well to reduce the amount of kerosene to
one part of the emulsion with from twelve to fifteen parts of soap-
suds. Where the insects are viviparous, or bring forth Uving
young, the spraying must be done systematically, at intervals of
four or five days, until no more young appear. On out-door
plants the same mixture may be used, but the spraying, if the
larvae come from eggs, need not be done more than twice, since
as a rule the eggs hatch at about the same time. On the Pacific
Coast lime, salt, and sulphur mixtures, and various resin washes,
have proved effective, but they are troublesome to make, and
hardly cheaper, all things considered, than the soap mixtures
above referred to. They act largely by sealing the scales to the
tree, so that the young cannot emerge or the adults are stifled ;
hence they are most effective where rains are few and far between.
The formulae for their preparation will be found in the chapter on
insecticides, where their range of usefulness is also stated.

The species belonging to the family AleyrodidcB resemble
scale insects in the immature condition, but are not fixed to the
plants, and in the adult stage both sexes are winged, somewhat
resembling minute plant-lice. The striking character by which
they may always be recognized is a covering of white, flour-like
powder, which renders them easily visible upon the leaves.
They are not common on out- door crops in the North, but are
not infrequent on house or conservatory plants, becoming more

122 AN ECONOMIC ENTOMOLOGY.

abundant and correspondingly more troublesome southward. A
species sometimes occurs in considerable number on orange. As
the insects live exposed in all stages, they are easily reached by
contact poisons, and of these the kerosene emulsion is usually the
most satisfactory. It kills them in all stages at moderate strength.

one part of emulsion in ten or twelve parts of water being ordi-
narily sufficient. Whale-oil soap is quite as effective, and is
preferable on some house or conservatory plants, while even the
pyrethrum extract is useful on a small scale, and is, perhaps, the
cleanest of all on house-plants.

THE INSECT WORLD.

123

It is a short step from the Aleyrodid^ to the plant-lice, be-
longing to the family Aphididce. Plant-lice are well known to
agriculturists by the injury they cause, and they are interesting
to the naturalist from their life history. Here we have the most
striking apparent exception to the general rule that insects are
developed from eggs, and yet perhaps the exception is more
apparent than real. At all events, parthenogenesis, or repro-
duction without the intervention of a male, occurs normally in a
large percentage of the species. Of course there are many differ-
ences in life habits, but a general account, covering most of the
cases, is all that can be attempted here. As a rule, plant-lice

Fig. 92.

a, female hop-louse, showing eggs through skin ; b, the stem-mother that starts the
transformation ; much enlarged.

winter in the &^% stage ; but this is subject to many exceptions,
especially in the warmer parts of the country. Early in spring,
as soon as there is a trace of reviving vegetation, these eggs
hatch. The insect that now appears is wingless, and usually
remains so, but grows rapidly by sucking the plant juices, and
soon begins to produce living young. It is called a "stem-
mother," because it is the source from which numerous genera-
tions issUe during the season. All the young born by this stem-
mother are, like herself, without sex ; that is, they are neither
males nor sexually-developed females. The rate at which they
are born varies, but as many as eight living young have been

124

AN ECONOMIC ENTOMOLOGY.

observed within a period of twenty-four hours from one specimen,
and it is not unusual to find, early in the season, a single large
louse surrounded by a group of anywhere from a dozen to
twenty or even more small specimens. The rate of growth also
varies, depending upon the weather ; indeed weather conditions,
early in the season, frequently determine the question of whether
or not certain species are to become injurious later on. A warm,
moist temperature favors their development, and reproduction
goes on at a rapid rate. Correspondingly, cold, wet weather
checks development, and may even destroy a large number,
especially of the young. Plant-lice, in their younger stages, are
exceedingly susceptible to sudden changes of temperature, and
at almost any time in the season a sudden drop of from fifteen to
twenty degrees, accompanied by a rain, will prove fatal to a great
proportion of them. But assuming that all is favorable, the
young that were first brought forth are in turn ready to repro-
duce in five or six days, and they also form little colonies ; this
method of reproduction continuing as long as food is plenty and
the weather mild. Experimentally, reproduction of this kind
has been continued for several years in succession, without any
tendency to develop sexed individuals or to produce eggs. At
almost any time after the first generation, specimens may become
winged, and these fly to other localities, forming new colonies
wherever suitable food is found. In this way they spread, and,
though they may have started from a single favorable locality,
yet in the course of a few weeks they may cover many hundreds
of acres. Exactly what determines the formation of wings in
some specimens and not in others is not known. We do know,
however, that the progeny of a single individual is variable, and
that while some become winged others do not ; but whether
winged or wingless, the specimens are equally without sex, and
all are viviparous, or bring forth living young. As the summer
advances, reproduction becomes less rapid. Plants tend to dry,
the supply of sap is not so plenty, and these features become
more marked through the autumn months until, with the ap-
proach of cold weather, plant growth entirely ceases. It becomes
necessary now to provide for the continuation of the species
during winter, and sexed forms are developed. The males are
usually winged and appear a short time before the females, which

THE INSECT WORLD.

125

differ by the lack of wings and the usually small size compared
with the normal sexless form. Pairing takes place as soon as
the female is sexually mature, and in a very few days after-
wards eggs are laid. In many instances the o^g^ supply is
exceedingly small, indeed there may be one only matured by
a female. Even this may remain within the body of the parent,
who simply dries up, the skin shrivelling around and form-
ing a protection to the ovum. More usually several eggs are
produced, and these of large size in proportion to the size of
the insect that lays them. They are green or greenish-brown

Fig. 93.

Hop-louse, male; return migrant.

in color when laid, sometimes yellowish, and frequently darken
to black. They are placed in sheltered situations on plants, and,
in the case of orchard trees, are usually found at the tips of twigs,
around the buds, or on the leaf-scales, where vegetation will first
start in the spring following. They are very firm in texture and
very resistant to insecticides ; in fact, it is impossible to destroy
them except by the most caustic mixtures. It has been already
indicated that there are many exceptions to this general life his-
tory, and one kind of exception we find where species feed dur-

126 AN ECONOMIC ENTOMOLOGY.

ing the summer upon a plant which dies down to the ground,
leaving nothing through the winter. In such cases there is an
alternate food-plant, upon which the winter and early spring are
passed. From this the insects migrate in early summer and to
it they return when cold weather sets in. Such a case we have
in the hop-louse, which spends the summer upon the hop, in-
creasing greatly in number in favorable seasons and often causing
much injury. When the vines mature and die, males develop,
and all the lice fly to plum-trees. Here the female is born, the
sexes mate, and eggs are laid. In the spring two or more gen-
erations mature upon the plum, and, when the vines are again
well started, winged forms develop and migrate to their summer
food-plant. This sort of migration is not unusual, although it
has not been traced out in many cases.

Another example we find in the "melon-louse," which has a
considerable range of food-plants, including cotton, orange,
strawberry, and nearly all the common weeds of our fields. If
circumstances favor their increase in spring, winged forms are
produced which migrate and settle upon melon fields, providing
for colonies during the summer.

The scientific problems connected with this method of repro-
duction and spread are of great interest, but cannot be entered
upon here ; the mere statement of the case being sufficient for
practical purposes. Plant-lice are so commonly known that a
detailed description of their appearance is unnecessary ; but it is
well to call attention to the presence of a pair of little tubes or
cornicles near the end of the abdomen, projecting from the upper
surface. These are called honey-tubes, and from them is excreted
a sweetish liquid known as honey-dew. Sometimes, when food
is abundant and the insects are active, the amount of sap they
pump out of the plants is so great that, in order to ease them-
selves, they void it in little streams through the anus, as well as
in drops through the honey-tubes. Thus the leaves of infested
plants become sticky or glazed with a sweetish liquid, on which
a black fungus rapidly develops, the leaf being frequently killed
by simply choking to death. Sometimes the vegetation beneath
a tree becomes thoroughly coated in the same way, or, when
shade-trees in cities are infested, the pavement becomes wet and
slippery with the viscid liquid. This honey-dew is often attractive

TilE INSECT WORLD. 1 27

to bees and wasps, who feed greedily upon it, and is yet more
tempting to ants, whose relations to plant-lice merit more than a
passing notice, since they are of decided economic importance.

It is a common thing to see ants crawling over leaves infested
by plant-lice, and it is often considered well that this should be
so, under the erroneous impression that the ants feed upon plant-
lice. In some cultivated fields ant-hills abound early in spring,
the little mounds scarcely rising above the surface, being seen
everywhere. We next find, shortly after, plant-lice infesting the
roots or leaves of the growing crop. In truth, ants are protectors
of plant-lice ; they are fond of their sweet excretion, and favor
their increase and development in every possible way. The
plant-lice seem to realize that they have nothing to fear, and
readily yield to the ants of their sweets whenever approached for
that purpose. Some species of aphids are indeed practically
dependent upon ants for their existence. Where some of them
lay their eggs we have not yet been able to learn, but perhaps
they simply drop them to the ground, where their color and size
render them invisible to our eyes. The ants find, gather, and
carry them into their galleries, where they store them until spring.
When vegetation starts and all conditions are favorable, the
eggs are taken where they can hatch normally, the young lice
being afterward carried to the plants upon which they are to feed.
An instance nearly like this, save that the young are carried over
winter, we find in the lice infesting corn roots, and undoubtedly
there are many others.

The study of plant-lice is difficult by reason of the matters
already set out, and it sometimes requires years to supply a miss-
ing link in their life history. The differences between tbem are
not always well marked, and the tendency has been to recognize
species as distinct when they feed on different food-plants. This
basis has proved erroneous, however, and now the wonder is to
find how many food-plants a single species may actually have.

It has been mentioned that a number of plant-lice feed upon
roots, and some species pass their entire life underground. Such
are the Rhizobiince ^ which sometimes become distinctly injurious,
as, for instance, when they occur on the roots of lettuce, in green-
houses and out-doors. Sometimes they are found on the roots
of trees or shrubs, quite usually attended by ants, which provide

128

AN ECONOMIC ENTOMOLOGY.

for their distribution. As they never come to the surface, so far
as we know, they are never winged, and are usually dull white
in color, or with a slight tinge of green. The body is covered
with a whitish powder and lacks honey-tubes.

Fig. 94.

Phylloxera vastatrix.—a. unaffected rootlet of grape ; b, rootlets with newly-formed
galls; c, same, with old and dried-up tissue; dd, groups of the lice on roots and root-
lets ; e,f, female pupa, from above and below; g, h, winged females; i, an antenna; j,
oviparous wingless female and her eggs; k, root showing location of the eggs.

An advance upon those root-living species is found in Phyl-
loxera, which belongs with Chermes in a sub-family, Chermesiiia,

THE LWSECT WORLD. 129

distinguished by having only two discoidal veins on the fore-
wings. The grape Phylloxera is known by reputation all over
the world, and its ravages in European countries have called
forth volumes of print. It has been thoroughly studied in our
own country by Dr. C. V. Riley, among others, and from his
works the following life history is taken.

The insect winters on the roots of grape, mostly as a young
wingless form. This starts growth in spring, rapidly increases
in size, and soon commences to lay eggs, the young from which,
like their mothers, remain wingless, are also sexless, and also lay
eggs ; and so we may have a series of generations of similar
creatures, no true sexes becoming developed, no wings appear-
ing, and reproduction being entirely through unfertilized eggs.
Sometimes, in midsummer, some individuals acquire wings, and
thus we get migrating forms, which issue from the ground while
yet in the pupa stage, and, as soon as they become winged, fly
and spread to other vineyards in the vicinity. Eggs are then
laid, usually on the under side of the leaves, from three to eight
being the range, while five is perhaps the usual number. They
are of two sizes, of which the larger produce females, the others
males, and they come from the eggs fully developed and ready
to reproduce. These curious creatures have become modified
for the one purpose of reproducing their kind, and can neither
feed, for the mouth is aborted, nor fly, for they have no wings.
After copulation a single ^%%, almost as large as the insect itself,
is developed in the female, and from it hatches a form which is
like the type which started the cycle early in the season. Curi-
ously enough, it occasionally happens that some of the wingless
forms which remain underground also lay eggs of two different
sizes, producing males and females, and thus it appears that
winged forms are not really necessary to the continuation of the
species. Quite usually wingless individuals abandon the roots
and crawl up the stems to the leaves, where they form the galls,
which are the most prominent external indications that a vine
is infested. I have seen vineyards in New York and New Jersey
in which almost every leaf showed these galls, yet withal no real
injury had been done. In other words, most of the native
American vines are able to sustain the attack of the species.
This is not true of the vines in Europe, where this insect has

9

I30

AN ECONOMIC ENTOMOLOGY.

been introduced, and, after a long series of experiments with
insecticides, none of which proved satisfactory, resort was finally-
had to American stocks upon which the foreign varieties were
grafted. This has proved effectual to an extent ; but it seems
that, in the course of time, the period varying somewhat, even

American stocks lose
^^^- ^^- their exemption in

Europe and become
gradually subject to
injury from the Phyl-
loxera attacks.

We have a number
of species of this same
genus infesting a great
variety of plants not
of economic interest.
Perhaps the most com-
mon is that which
forms large, blister-
like galls on hickory
leaves, so prominent
as to attract attention
from even the most
casual observer. If one of these galls be cut open, the inside
will be found lined with numerous minute, yellow insects, with
dusky wings which lie folded flat over the back, and in this par-
ticular the Phylloxera differs from the typical aphids, which have
the wings vertical when at rest.

The subject of dealing with underground pests, or plant-lice
which feed upon roots, is one of importance, upon which the
last word has not yet been said. As against the Phylloxera,
bisulphide of carbon has proved useful, injected by means of a
proper instrument into the ground at about the level of the roots
and allowed to permeate the soil. The fumes are deadly to
insects, and where they reach them in any but the &^^ stage,
kill. The Phylloxera does not require attention in our country
at the present time, and no large space need be given the subject
of remedies against it. The matter is different when we consider
the species which infest other cultivated plants ; whether Rhizo-

Galls of Phyllo.xera on grape-leaf.

THE INSECT IVORLD.

131

biini, or forms like the "peach-louse" or the '"woolly apple-
louse," where they may be on leaves, twigs, and roots at one or
different times. Bisulphide of carbon can be used with good
effect in such cases ; but it is rather an expensive application, and
there is an element of danger that makes it desirable to employ
something equally effective yet less liable to injure vegetation.
Very satisfactory results have been obtained with tobacco, some
under my own observations, some reported by other trained
observers, and it seems fairly well proved that trenching around
an infested tree, and filling into the trench a liberal supply of
ground tobacco, refilling the trench immediately after, will have
the effect of clearing the roots of these pests. This has been
used more particularly against the peach aphids, and has been
almost uniformly successful. Tobacco is a good fertilizer, and
many dealers carry the coarsely ground product as part of tiieir
stock in trade. It is rather expensive as a fertilizer, but cheap as
an insecticide, and a double value is obtained because besides
killing the lice it also stimulates the trees or other plants. The
use of tobacco, therefore, where root-lice are troublesome, is
good farm practice. It may be well to say, however, that little
or no benefit is derived from the use of stems spread upon the
surface, or dug in, because there is not a sufficiently rapid extrac-
tion of the nicotine, and this is, after all, the killing agent. The
ground material on the other hand gives up its nicotine readily
to a small quantity of moisture, and it will be quickly carried
down and around the roots of the plants, into direct contact with
the insects. In land infested by root-lice the use of commer-
cial fertilizers is indicated. It has been found by experience that
salty mixtures kill plant-lice more or less rapidly, and therefore,
where root-lice are present, potash in the form of kainit and
nitrogen in the form of nitrate of soda are advisable. I have
frequently noticed that on land where these fertilizers are used
underground insect life is scant, and direct experiments have
proved that this condition of affairs is largely due to the salty
fertilizers introduced into the soil. As against peach-lice in light
soil, ten pounds of kainit to a five- or six-year-old tree of good
size is about right, and the material should be spread on the
surface evenly as far as the roots are likely to extend.

In the more normal plant-lice the wings are better developed,

132

AN ECONOMIC ENTOMOLOGY.

and we find differences in the form of the honey-tubes which are
of generic or even sub-family value. Thus, we have some species
of Pemphigus entirely without them, or with very small, mere
tubercle-like structures. They live on a variety of trees, but
perhaps more abundantly on poplar, and make galls, which are
sometimes spherical and nearly half an inch in diameter. If we
cut one of them after midsummer, we find it full of plant-lice,

Fig. 96.

Cock's-comb gall on elm, Colopha ulmicola.—a, elm-leaf showing galls; b, winter
egg, covered by the skin of the true female; c, larva just hatched ; d, pupa; e, winged
adult.

the progeny of the single specimen which caused the growth of
the gall early in the season. There are many other gall-producing
lice, perhaps the best-known being the Colopha ulmicola, found on
elm, and forming the "cock's-comb" gall. The popular name
fairly describes the appearance of the abnormal growth, which
is an inch or more in length and about one-quarter of that in
height. None of these gall-making species are abundant enough
to be seriously troublesome ; but quite the contrary is true of the

THE INSECT WORLD.

133

Woolly apple-louse, Schizoneura lanigera: show-
ing a group of specimens on bark, a crevice on a
branch, in which they congregate, and a winged
form.

" woolly plant-lice," belonging to the genus Schizoncura. These
cover themselves with a secretion resembling fine cottony fibre,
which conceals them more or less completely. Thus there may
appear to be tufts of cot ., ,

ton attached to leaves
or twigs, beneath each
of which we find, how-
ever, a great mass of
plant lice busily en
gaged in feeding. The
' ' alder - blig'ht' ' and
' ' beech-blight' ' are due
to species of this kind,
and more important
than all is the ' ' apple-
blight," or " the woolly
apple-louse. ' ' This spe-
cies, Schizoncura la7ii-
gera, has been intro-
duced into other countries, and is known in England and Aus-
tralia as the "American blight." Young trees are frequently
injured by these aphids, which gather in masses on the trunks,
and cause the death of the bark below the point of attack. The
eggs may be found

singly in the bark ^'^- 98-

crevices during win-
ter, completely envel-
oped in the dry skin
of the female, and
from them appear, in
spring, agamic, wing-
less forms, which bear
living young. This
method of reproduc-
tion continues until the
winged type, which
spreads to other localities, is produced in late summer. The
sexed forms are wingless and mouthless, the female producing
only a single Q^g ; but in the southern parts of our country it

Schizoneura latiigera. root form. — a, galls caused by
them on apple-roots ; b, wingless, wax-coated form ; c.
winged form.

134 ^^ ECONOMIC ENTOMOLOGY.

is not unusual for tlie insects to survive winter in the adult con-
dition, without producing a winter &^%. One form of the species
works deep underground on the fibrous roots ; and this is most
difficult to deal with, and often causes the death of the attacked
trees. When they appear on the trunk, treatment with either
whale-oil soap or kerosene emulsion will be effective, and the
underground form can be reached with bisulphide of carbon, or
by a liberal use of the tobacco or kainit, as recommended on a
previous page.

We have a number of species that attack our common orchard
and farm crops, like the cherry-aphis, Myziis cerasi, the peach-
louse, Aphis persicae-niger, the apple-louse. Aphis mali, the
hop-louse, wheat-louse, melon-louse, and others of equal reputa-
tion. Almost every species requires different treatment, and it
is difficult to lay down general rules. Cabbage-lice, which fre-
quently do great injury, can be kept down by the prompt removal
of all plant remnants left in the field after the heads are taken out
and disposed of On the stumps the insects continue to breed
and live during the winter, if not disturbed, either as eggs or
adults ; therefore, remove, use up, or destroy them as soon as
may be. In pits where cabbage is kept to obtain seed the year
following, a great number of lice pass the winter safely, but a free
use of bisulphide of carbon will result in their destruction, so that
the plants may be set without infestation in spring. An equally
important point is keeping down all cruciferous weeds Uke mus-
tard, shepherd' s-purse, and the like, because on these the insect
flourishes as well as on cabbage ; therefore, clean culture, not
only in the fields but along fences and roads, will pay over and
over again. The corn-root louse can best be attacked through
its guardian ant, which colonizes the helpless forms upon the
roots in spring. Late fall-plowing the corn-fields is indicated
here, that the nests of the ants may be destroyed at a season
when they are unable to rebuild them. In those sections where
fertilizers must be used, the kainit and nitrate of soda, already
referred to, will prove effectual. The ' ' apple-louse' ' and ' ' cherry-
louse," though different in appearance and habits, have a similar
life history, and both pass the winter in the &gg state, the eggs
being laid on young twigs close to the buds. It is good policy
to trim a tree on which there are many eggs pretty thoroughly in

THE INSECT WORLD.

135

winter, the cuttings, of course, to l)e i)roni|)tly destroyed. Thus
the number of individuals to start new infestation in spring
will be greatly reduced. They breed aganiically throughout the
summer, and bring forth the sexed individuals late in fall or
early in winter. I found them in New Jersey still ovipositing
during the first week in Deceml)er. Where pruning is not de-
sirable, much can be done by spraying the trees, as soon as the
eggs have hatched, with kerosene emulsion, — say, one part in
twelve or thirteen of water. Both of these species lay a number
of eggs, but how many has not, I believe, been actually deter-
mined. The species that infests hops has been already mentioned,
and the best remedy again.st it is the total destruction of the vines
immediately after the hops have been gathered, which will head
off the production of the sexes. If this is delayed, spraying the
plum-trees in fall or early in the spring before the hop-vines have
made much start will be of great advantage. When the insects
infest such plants as wheat, rye, or oats, it becomes difficult to
adopt measures likely to be of much benefit. They multiply so
rapidly, and the task of spraying a wheat-field is so enormous,
that it is hardly worth while to recommend it. In such cases
we must stimulate, to assist the plants in outgrowing injury, by
applying such readily soluble fertilizers as nitrate of soda. This
gives additional vigor to the plant, enabling it to sustain the
attacks of the insect and mature a crop as well. Harvesting
should not be delayed longer than absolutely necessary, unless it
is observed that the enemies of the plant-lice are getting the bet-
ter of them, and in that case nothing will be lost by leaving the
grain as long as desirable. The aphid infesting cucumber- and
melon-vines has been recently determined to be the same as one
of those infesting oranges, and as that which frequently injures
cotton. It has also been found on the strawberry, and seems,
indeed, to be a very general feeder, passing the winter upon
such wild plants as remain more or less green. Under favorable
circumstances it increases rapidly in spring, and a migration
starts to cultivated fields. Against this insect on melon-vines
we can use bisulphide of carbon, covering the plants with a bowl
or other covering, and evaporating a small quantity beneath it.
This will kill the aphids in about an hour, and, though the pro-
cess is slow, it has the advantage of being completely effective.

136 AN ECONOMIC ENTOMOLOGY.

While, as has been stated, we cannot lay down general rules
as to the treatment of all plant-lice, there are a few points that
are always important. In the first place, the earlier the insects
are dealt with, the more chance there is for the application to be
effective. Plant-lice should be treated just as soon as they are
noticed ; the longer the delay the weaker the plants become, and
the greater the thoroughness required to reach all the specimens.

As a general insecticide, nothing is better than the kerosene
emulsion, which, when diluted ten times with water, kills all the
young forms and adults of the green species. It has been found
by experiment that black or brown species are much more diffi-
cult to destroy, and one part of emulsion in six or eight parts of
water is more likely to be effective. Fish-oil soap is effective at
the rate of one pound in six gallons of water ; or, as against the
brown species, one pound in four gallons of water. Thorough-
ness of application is always essential. It must be remembered
that these poisons act by clogging the spiracles, or by entering
into the body through them. Unless the application is thorough,
the insects may be weakened but not killed, or, if rendered help-
less for a time, they may recover, and a second dosing becomes
necessary where one, more thoroughly applied, would have been
sufficient. Where it is not advisable to apply either of the ma-
terials mentioned, we can use tobacco with good prospects of
success, either as a decoction or a very finely ground powder.
In greenhouses, tobacco is a standard remedy, and its frequent
application results in keeping them moderately free from these
pests. It may be applied as already described, but is more usu-
ally burnt to make a smoke, which is poisonous to the insects.
A milder method is to keep the steam-pipes covered with moist
stems, so as to produce a nicotine-laden atmosphere. Very often
plant-lice appear in forcing-beds, and these we can generally
destroy with bisulphide of carbon placed in a shallow dish and
left in the covered beds overnight. Greenhouse benches may
be rid of the pests in the same way, covering the plants for two
or three hours with a frame or box, and evaporating a small
quantity of the bisulphide. A fumigating-box made of wood,
canvas, tin, or other material, large enough to contain potted
plants of good size, should be in every greenhouse and nursery.
A number of pots of infested plants may be placed in such a box.

THE I A- SECT WORLD.

137

the door closed, and bisulphide evaporated Iroiii a vessel hung up
just below the top of the box. As the vapors descend, they will
kill the inserts infesting the plants, which may then be sent out
free from all insect troubles. One dram of liquid per cubic foot
of space will be about the right quantity not likely to hurt vege-
tation, while killing all lice by the time the liquid has entirely
evaporated.

The "jumping plant-lice" are so called from their habit of
leaping readily, though, as a matter of fact, their resemblance is
rather to the tree-hoppers, and most of all they recall a miniature

Fig. 99.

The pear-psylla. — a, pupa from under side, showing the thread-like piercing lancets;
to the right, a winged adult and stalked egg.

cicada. They all belong to the family Psyllidce, some species of
which are exceedingly troublesome, — e.g., the "pear-psylla,"
Psylla pyricola. This infests pear-trees in the more northern
parts of the country, extending south to Maryland, though
south of New York State it occurs in isolated patches only. It
does its injury, first, by sucking the juices of the plant and so
weakening it ; second, it exudes honey-dew in such quantity as
actually to close the pores of the leaves and young bark, over
which a fungus forms and checks growth. It commonly attacks
the stalk of the fruit, or the twig just where it is fastened, and
the result is nearly always a cessation of growth in the pear itself.
The species has several broods during the season, bift winters as

138 AN ECONOMIC ENTOMOLOGY.

an adult in any available shelter, — under loose bark of trees, under
rubbish, and, in fact, wherever there is an opportunity to hide.
The application of whale-oil soap early in spring, just as the buds
begin to swell, will generally kill the insects, which are then ready
to emerge from winter quarters. Good practice is to scrape all
the loose bark from the trees during the winter, and burn it ;
wash at that time with a potash or strong kerosene mixture, and
in spring use the whale-oil soap at the rate of one pound in one
gallon of water, being careful to confine the spraying to the
trunk and larger branches. If this is thoroughly done, it forms
a film over the trunk which no insect will voluntarily pierce, A
liberal application of whitewash is also advantageous, and should
be put on with a knapsack sprayer and Vermorel nozzle.

We have many species belonging to this family, some of them
gall-makers on the hackberry, or Celtis ; but none others occur in
sufficient numbers to be of economic importance.

The ' ' tree-hoppers' ' belong to the family Membracidce, and
contain many odd-looking types. The general shape has been
compared to a beech-nut, and the most prominent part is always
the thorax, which may be produced into a curved horn forward,
into a broad hump, into a pair of curved lateral horns, into a
double hump, or into a dozen other forms. The species occur
on trees, shrubs, vines, and indeed on vegetation generally,
though rarely in great numbers. Some species excrete honey-
dew, some lay their eggs in white frothy masses on plants, and a
few are attended by ants, thus resembling the plant-lice. Only
a few are troublesome, and of these are the "buffalo tree-
hoppers," belonging to the genus Ceresa. They derive their
common name from the fact that the thorax is cut ofT square
anteriorly, and projects into two short, lateral, curved horns,
which give it a fanciful resemblance to the massive front of a
buffalo. The head is small and scarcely noticeable, the horns
not being recognized at first as really belonging to the thorax.
This insect causes injury by laying its eggs in slits on twigs of
apple- and other fruit trees. There appears to be almost a poi-
soning of the plant tissue, because the wounds, though apparently
slight, do not readily heal over, but rather open up the year
following, giving rise to an abnormal swelling, weak and morbid
in character, unable to sustain the weight of any fruit that occurs

7HE INSECT WORLD.

139

beyond it, and ready to break in the (irj,t iiigh wind. On old or
large trees the insects are rarely dangerous, because their injury
results in only a litde pruning, but on young trees they may
cause deformities ; hence, if the insects are noticed in a young
orchard, it will be advisable to go over it carefully during the
winter, to trim out all infested twigs or branches, burning the

Fig. 100.

Buffalo tree-hopper, Ceresa btibalus.—a, adult; b, c, d, tarsus, antenna, and wing; /, ^,
tip of abdomen, showing ovipositor.

cuttings to destroy the eggs. Active insecticide applications are
hardly indicated.

Next come the cicadas, or "harvest-flies," often miscalled
locusts, and the largest of the Homoptera. They are easily known
by their broad, transparent wings, the large head with prominent
eyes set on each side, and by their intensely shrill, loud song,
which during midsummer forms one of the common sounds
of the country. The author of this concert is the ' ' dog-day
har\'est-fly," greenish in color, more or less marked with black.
The noise is produced by an elaborate drumming and resonating
structure on the under side of the thorax and abdomen of the

140

AN ECONOMIC ENTOMOLOGY.

males, who alone are musical, giving rise to that oft-quoted old
saying,—

' " Happy the cicadas' lives,

For all have voiceless wives."

The plan of the sound-organs can best be described by com-
paring to a slightly convex-bottomed tin pan, which makes a

Fig. lor.

I

Fig. I02.

a, Ceresa bubalus. ovipositing in slits b ; the
eggs, d, arranged as at c ; old, scarred punc-
tures shown at e.

The dog-day harvest-fly,
Cicada tibicen.

snapping noise whenever the bottom is forced to change from
convex inwardly to convex outwardly. By an exceedingly rapid
snapping of the convex "drum" of the cicada, the continuous
shrilling sound is produced, intensified and modified by the vari-
ous tense membranes more or less surrounding it.

The most famous species of this family is the "periodical
cicada," or "seventeen-year locust," Cicada septendecim. It is
of especial interest from the unusually long larval period, re-
maining in the Middle and Northern States sixteen years beneath

THE INSECT WORLD.

141

the surface of the ground, feeding on the juices of roots, and
transforming in the spring of the seventeenth year into a winged
adult. No less than twenty-two broods have been tabulated in
the United States, chiefly through the efforts of the late Dr. C.
V. Riley, so that we know approximately how each is distributed,
and are able to foretell with certainty when the insects will appear
and about what territory they will cover. A further point of

F^iG. 103.

The periodical cicada, C septendecim. — a, pupa, ready to change; b, pupa-skin from
which the adult c has emerged ; e, eggs, taken from the egg-punctures d.

interest is that in the more southern States the period of develop-
ment is somewhat shorter, thirteen years only being required to
bring the insect to maturity. Much confusion was caused in
arranging the broods until this fact was understood ; but experi-
ments have now been made in transferring eggs of the thirteen-
year variety to northern regions, and eggs of the seventeen-year
variety to southern regions ; the object being to ascertain whether
climate would affect the larval period in the first generation.
These experiments have not yet terminated. This cicada makes
up for the long intervals at which it occurs by the enormous
numbers in which it appears, and in a " locust' ' year its loud

142

AN ECONOMIC ENTOMOLOGY.

Fig. 104.

song may be heard at all periods of the day and until late into
the night, from the end of May to nearly the end of June, louder
and more intense on warm or hot days. No injury is done by
the insects in feeding, but their egg-laying habits often cause

considerable trouble. Though
the larvae feed under ground, the
eggs are laid in the twigs and
branches of trees ; a series of slits
being cut by the powerful ovi-
positor of the female, forming
smooth chambers in which the
eggs are arranged in series.
There is nothing to be done when
such a brood occurs except take
the injury and make the best of
it. Of course valuable plants or
trees can be protected by mos-
quito-netting, but my statement
applies to ordinary farm and or-
chard crops. The fact that we
know when the insects are to
appear makes it possible for the
fruit-grower to guard himself to
some extent by not setting out
young stock. On old trees no
serious injury will be done, and
if no pruning is attempted during
the winter preceding, the insects
will probably find an abundance
of useless twigs to oviposit in.
Young trees, however, are some-
times so injured as to make them
practically useless, either by com-
pletely spoiling the shape, or by
so weakening the main branches
that they never become strong enough to bear a proper top.
Wherever the English sparrow has been introduced, the period-
ical cicada is doomed. These birds seem to have an intense
hatred for the insects, attacking and pulling them to pieces in

Cicada egg-punctures : at a, freshly
made; at b, old and distended.

THE IXSECT WORLD.

M3

the most wanton manner. Near the large cities where the spar-
rows are numerous, entire broods have already been destroyed.
In 1889 the insects appeared in large numbers in Prospect Park,
Brooklyn, and in the surrounding woodland, but in an entire
day's careful search I found only a_ single branch containing
eggs !

That it may be known in a general way where and when these
insects may be expected, the following record of the broods is

Fig. 105.

1] ;'|

;

'1 I/I

i

1

i

'

Cicada egg-punctures, seen at a, from outside ; 5, cut down on puncture to show the
two chambers ; c, side view of an egg-chamber ; d, a pair of egg-chambers from which
the eggs have been removed.

given, with the date of last appearance, the time when they may
be next expected, and the country covered by them. The state-
ment is made up from the reports and bulletins of the United
States Department of Agriculture.

Brood I. last appeared in 1893 ! ^^'^^1 appear again in 1910.
Occurs in Massachusetts and Connecticut in small numbers.

Brood II. appeared last in 1895 ; will appear again in 1908.
It covers the northwestern part of Georgia, and appears at thir-
teen-year intervals. No very definite limits have been assigned
to it.

Brood III., originally supposed to occur in Ohio in 1887, was
based on erroneous information.

Brood IV. is of the thirteen-year variety, appeared last in
1883, and will appear again in 1896, covering parts of Florida.

144

AN ECONOMIC ENTOMOLOGY.

Alabama, Mississippi, and Tennessee, but it seems not to be
very numerous.

Brood V. occurred last in 1888 and will appear next in 1905.
It covers parts of Southern Wisconsin, Northern Illinois, the
eastern third of Iowa, the northwest counties of Indiana, and the
more southern part of Michigan. This brood is very numerous
in individuals.

Brood VI. occurred last in 1884 and will occur again in 1897,
being of the thirteen-year race. It occurs in the southwestern
part of Mississippi and extends into Louisiana, infesting a com-
paratively small territory only.

Brood VII. occurred last in 1885, and will occur again in
i8g8, being also of the thirteen-year race. It occurs in South-
ern Illinois, Kansas, Missouri, Georgia, Louisiana, Arkansas,
Mississippi, and Tennessee.

Brood VIII. appeared last in 1889, and will appear again in
1906. It covers a portion of Southern Massachusetts, a large
part of Long Island, extends along the Atlantic Coast to the
Chesapeake Bay and for some distance into Pennsylvania, Ken-
tucky, West Virginia, Ohio, Indiana, and Illinois

Brood IX. occurred last in 1891 and will appear again in 1908.
It occurs in parts of Nebraska and probably in portions of Colo-
rado, though it has not yet been satisfactorily limited.

Brood X. occurred last in 1888 and will appear again in 1901,
being of the thirteen-year race. It has been recorded from Texas,
but is yet a doubtful brood, requiring fuller observations than
have been made to substantiate it positively.

Brood XI. occurred in 1893 and will occur again in 1910. It
is a large one, covering parts of North Carolina, Virginia, Mary-
land, Illinois, and Indiana, although not the entire State in any
instance.

Brood XII. occurred last in 1894 '^"d will make its next ap-
pearance in 191 1. It extends along both sides of the Hudson
for its full length, into Southern New York, Connecticut, through
the entire State of New Jersey, and into Pennsylvania, Ohio,
Michigan, North Carolina, Virginia, Maryland, and Delaware.

Brood XIII. appeared in 1895 and will appear again in 1912.
It occurs throughout a large part of Iowa, and probably a portion
of Illinois and Missouri.

THE INSECT WORLD.

145

Brood XIV. will appear in 1896, and covers Western Missouri,
extending into Kansas, Arkansas, Iowa, Northern Texas, and
Indian Territory.

Brood XV. will occur in 1897 in Western Pennsylvania and
Ohio, extending into Kentucky and West Virginia.

Brood XVI. appeared last in 1893 and will appear again in
1906, being of the thirteen-year race. It occurs in the northern
portion of Georgia, but its limits are not well defined.

Brood XVII. will appear next in 1898 and at intervals of
seventeen years thereafter. It occurs in Wisconsin, the north-
ern part of Ohio, Pennsylvania, and parts of New York, as well
as isolated localities in New Jersey. The brood is a small one,
however, especially in the southern part of its range, and appar-
ently dying out.

Brood XVIII. occurred in 1894 and will occur again in 1907,
being of the thirteen-year race. It is a very well-recorded one,
and covers Southern Illinois, nearly all of Missouri, Louisiana,
Arkansas, Indian Territory, Kentucky, Tennessee, Mississippi,
Alabama, Georgia, North and South Carolina.

Brood XIX. occurred last in 1882 and will occur again in

1899. It is a small one and confined to a few counties in Central
and Northern New York,— that is, Monroe, Livingston, Madi-
son, Yates, and, perhaps, those immediately adjoining.

Brood XX. appeared last in 1883 and will appear again in

1900. It occurs in Western New York and Pennsylvania and
Eastern Ohio. It is a small brood and does not attract attention.

Brood XXI. occurred last in 1884 and will occur again in

1901. It covers parts of North Carolina, Virginia, and West
Virginia, and may possibly occur in Massachusetts (Martha's
Vineyard) as well.

Brood XXII. appeared last in 1885 and will appear again in

1902. It occurs on Long Island, in New York, New Jersey,
Pennsylvania, Delaware, Maryland, District of Columbia, Vir-
ginia, West Virginia, North Carolina, Tennessee, Georgia, Ohio,
Kentucky, Indiana, Illinois, Michigan, and Wisconsin. Brood
VI L, of the thirteen-year race, and Brood XXII. , of the seventeen-
year race, come in contact in Southern Illinois and Northern
Georgia, and it may happen, as it did in 1885, that these two
broods appear during the same year at the same place.

10

146

AN ECONOMIC ENTOMOLOGY.

The FjilgoridcB^ or ' ' lantern-flies, ' ' contain some very remark-
able and striking species in tropical countries, but are sparsely-
represented by somewhat rare
Fig. 106. species in our fauna. Perhaps

the most comraon of our forms
are species m^On}ie?iis, pale
green or whitish, having some-
what the appearance of small

wedges, the broad wing-covers
being flattened vertically. They
may be found on the under side
of leaves of various plants, par-
ticularly grape, sucking the
juices, preferably from' the larger
veins or ribs. None of them are

injurious, and the family is mentioned only that our common

species may be recognized.

The "spittle-insects," or "frog-hoppers," of the family Cer-

copida, resemble some forms of tree-hoppers in their habit of

laying the eggs in little,

FulgoriAcB , or lantern-flies. — a, Scolops
sulcipesY^b, Poeciloptera truncaticorms ;
twice natural size.

^ Fig.

107.

frothy, white masses. These
masses of ' ' frog-spittle' ' are
often noticed in grass lands,
but their true character is
rarely understood. Unlike
the "tree-hoppers," the
Cercopidce never have horn-
like processes or projections,
but are usually squat, some-
what angular, yet flattened
creatures, whose popular
name, "frog-hoppers," has
been obtained by the some-
what fanciful resemblance of the insects to a frog when just ready
to leap. Few of these species, so far as I have any information,
are sufliciently injurious to be of economic importance. They
feed on a great variety of plants, but are rarely common on culti-
vated crops.

It is different with the "leaf-hoppers," or Jas sides, which are

Cercopid, or spittle-insect. — a, larva, en-
larged; d.same, natural size, on a leaf bearing
"frog-spittle;" c, the adult, enlarged.

THE INSECT WORLD.

147

small, slender insects with the wing-covers narrow and slightly
thicker than the broad hind wings, which are the only effective
organs of flight. The thorax is broad and square, the head
usually short and very broad, in most cases somewhat crescent-
shaped, with prominent eyes occupying a large part of the sides.
If we examine the insects on the under side it appears as if the
beak or rostrum came out from the breast between the front legs,
so much is the head curved under. The antennae are very short
and bristle-like ; the legs are well developed, the hind pair espe-
cially being very long and powerful, set with spines on the tibiae,

Fig. 108.

Development of a Jassid, Agallia sanguinolenta.—a, larva; b, pupa; c, adult; also head
of same from below.

somewhat as in the grasshoppers, and like them the insects are
powerful leapers. This they are in all stages, but as adults they
are also ready fliers, and hence difficult to capture. Many of
them are common and, feeding on cultivated plants, are injurious.
As in other families, there is considerable difference in the life
history of the species ; but of most of those of economic impor-
tance it may be said that they pass the winter in the adult stage,
hiding in all sorts of rubbish or in crevices, wherever they find
opportunity. Some time in spring they leave their winter quar-
ters, attack the plants upon which they feed, and lay eggs. The
number of hibernating individuals is usually not very great, but
they lay a large number of eggs, and the young and future broods
become troublesome. One of the best-known species is that

148

AN ECONOMIC ENTOMOLOGY.

The grape-leaf-hopper, Erythroneura vitis ; at rest,
and with wings expanded.

found on grape-vines, which causes the leaves during the latter
part of the summer to become marked with brown spots, some-
tmies in such numbers that they become confluent and the entire
leaf is "burnt." If we tap a leaf at this time swarms of little
creatures, not exceeding an eighth of an inch in length, prettily

marked with green, rosy-
^'^- '°9- red, and yellow, will fly

or jump from them.
Earlier in the season
they are yellow or green-
ish, without wings, but
jump readily if disturbed.
On roses we find a simi-
lar appearance, and here
the species are green or
yellowish, without much
marking. Many are the crops infested by these little hoppers,
and, though there are good characters by which they can be
distinguished scientifically, yet to ordinary observation they
appear much'alike, except in size and color.

The methods of preventing injury are much the same for all
species. In the first place, where experience has shown that the
insects are likely to occur during the summer, all rubbish should
be disposed of in the course of the winter preceding. This can
be done by collecting and burning, or by plowing under very
early and cultivating so as to leave a clean field. Loose bark,
dead branches, twigs, or scaly fence-posts should all be attended
to, and piles of dead grass or weeds along fences or in corners
should be burnt or otherwise destroyed. In this way much can
be done to prevent the insects from getting a start. When the
larvae are first noticed great success has been attained in vine-
yards by walking along the sides of vines strung oh wires, dis-
turbing them to start the insects, which jump wildly and readily.
A shingle or palm-leaf fan smeared on both sides with coal-tar or
insect-lime should be kept in constant motion near the vines, and
by this fanning a great quantity of the jumping larvae will be drawn
to the smeared surfaces and destroyed. This method is practical,
and has been found effective within my own experience ; so large
a proportion of the insects being captured in the course of two

Tlifi INSECT WORLD. 1 49

days that subsequently they were not noticeable. If this method
cannot for any reason be used, the kerosene emulsion diluted ten
times may be applied, and the vines should be disturbed as the
spraying is done. If a Vermorel nozzle is used, it can be held
a little distance from the vines and will hit the insects while they
are in the air, either jumping or flying. The wetting done in
this way is as effective as when done on the leaves, and there is
even more chance of hitting them in the air than at rest. So the
effort should be to fill the air around the vines, for some little
distance, with the fine mist-like spray so easily produced by the
Vermorel nozzle. This method should also be made use of if the
insects are found in numbers after they are winged. It is appli-
cable in many cases, but hardly practical where insects feeding
upon wheat or similar plants are to be dealt with. It has been
found that the adults are attracted to light, and the electric arc-
light, particularly, destroys myriads of them. I have seen in a
single globe no less than one pint of leaf-hoppers, and the num-
ber included in that measure is almost impossible of estimate.
The unfortunate feature in this method is that the damage to
vegetation has been done when it takes effect, and it is in the
line of preventing injury during the year ensuing, which can
be accomplished as readily by the winter treatment. In fact,
cleaning up during winter is strongly insisted upon, and will pay
many times over. A great number of leaf-hoppers are found in
grass lands, where they do much more injury than is generally
supposed, — an experiment in Iowa seeming to prove that just
about one-half the crop is destroyed in badly infested fields. The
experiment was made by setting off two patches of equal size, as
nearly equal in all respects as could be made, leaving the one
untreated and collecting the leaf-hoppers from the other. Cattle
were pastured on both parcels, and that on which the insects
were collected supported just double the number. The insects
were collected by means of shallow pans coated with tar, drawn
by man or horse-power, and in jumping or flying up before it they
alighted immediately behind the edge, upon the tar. It requires
very few such collections to practically exterminate the pests on
a tract of land, but of course the question remains whether it
will pay. On grass lands winter treatment is hardly practicable,
and collecting in pans is perhaps the only available method.

ISO

AN ECONOMIC ENTOMOLOGY.

Fig. iio.

A water-boatman, Notonecta species.

Fig. III.

The sub-order Hetcroptera conrains those species of bugs in
which the upper wings are thickened toward the base and the

terminal portion is membraneous
and veined. We have a large
number of species belonging here,
and some large series may be en-
tirely left out of consideration.
Such, for instance, are the
aquatic families, all of which seem
to be carnivorous in habit,
whether they live on the surface
of the water or beneath it. One
of the water-boatmen, a species of Corisa, may be mentioned,
because its eggs are used as food in Mexico. These eggs are
nearly white in color, about one-tenth of an inch in diameter, and
laid in great numbers on sedges, where they are collected by the

natives. Judging from the usual odor
of the bugs and from the taste of
such eggs as are sometimes involun-
tarily eaten on fruits, it requires a
specially-developed gustatory appa-
ratus to enjoy a meal of this char-
acter. This suggests the fact that
one of the peculiarities of this sub-
order is the more or less marked
presence of odors, differing some-
what in kind, but all of them intensely
disagreeable. In bed-bugs we have
one type in marked perfection, while
in the "squash-bug" we find an ex-
cellent illustration of another.

One of the water-bugs that some-
times attracts attention is a huge
creature, two or three inches in
length, broad in proportion, livid
gray in color, flattened above, with
a short beak and very large, thick-
ened forelegs, often drawn in considerable numbers to electric
lights. It is the Bdosto7na americana, which lives in ponds and

Belostonia americana.

THE INSECT WORLD.

151

streams, where it fceds on other insects and small fish, destroy-
ing large numbers. During the night the winged individuals
leave the ponds, pair, and fly to new localities to lay their eggs.
So abundantly do they occur that they sometimes become nui-
sances near electric lights, and have been termed from this fact
' ' electric-light bugs. ' '

Sometimes we find slender, spider-like creatures of a brown
color scudding over the surface of the water at a rapid rate, and

Fig. 112.

A water-strider, Rheitmatobates rileyi, female. — a, anterior tarsus ; b, ovipositor ; c, hind

tarsus.

these are "water striders," or Hyd^'obatidcs. They are inter-
esting because some of them pass their entire lives upon the
ocean, miles from land. These are said to feed upon the juices
of such dead fish and other animals as they find on the surface,
and probably also on the floating masses of sea-weed occurring
in equatorial regions where they are most common.

The first family of economic importance among the terrestrial
species is the Redtiviidtz, containing species of quite large size.

152 AAr ECONOMIC ENTOMOLOGY.

distinguished by a comparatively small, narrow head with promi-
nent eyes, and by a short, very stout, curved, pointed beak,
which rests, when not in use, in a little groove between the
front legs. The insects are strongly built, with legs usually well
developed, and, as they are predaceous, are to be regarded as

friends. The very small
F^*^- ^^3- head and short, slightly

yc-j^^21Si^^f—p — -^^ curved, pointed beak, serve

to distinguish them from
the plant-feeding species.
They readily puncture the
skin of any one handling
them carelessly, and the

Wing of Heteropteron with all the regions <,i •. t. • ^• 1

named. L)ite IS cxceedmgly pam-

ful, the poison injected
into the wound being intensely irritating, and sometimes causing
considerable swelling, with pain lasting for days. One of the
species has adapted itself to life in houses, feeding upon flies and
bed-bugs. The young have the curious habit of coating them-
selves with particles of dust or fibre which conceals them perfectly
from casual observation. A similar species, Conorhinus sangui-
sugis, nearly an inch in length, is found in houses in the South-
ern States, — not to feed on bed-bugs, however, but as a bed-bug
itself It is especially inclined to bite children, and many cases
of supposed spider-bites are believed by Dr. Leconte to be really
due to this insect. He also states that he has known a patient
to suffer from the effects of such a! " bug" bite for nearly a year.
Fortunately, the insects are not very common, their large size
and black color, with red markings, making them easily visible
and readily destroyable.

The largest species occurring in the Eastern United States is
the so-called "wheel-bug," Prwiidus cristahis, and this becomes
more common southwardly. It lays its curious, jug-like eggs in
hexagonal masses on bark of trees, fences, or any other conven-
ient locality, and the adult, which is brown in color, is one of the
most readily recognized of our species. The thorax has a semi-
circular crest, the edge of which is toothed, so that, viewed from
the side, it has somewhat the appearance of a segment of a cir-
cular saw. It attacks all sorts of insects, piercing them with its

THE INSECT WORLD.

153

powerful beak and sucking their juices. There arc other species
of the same general appearance common everywhere, and some
even maintain themselves in our cities, feeding upon the larvae
injuring shade-trees. I have noticed certain of them in New
Brunswick destroying the larvae of the elm-leaf beetle in large

Fig. 114.

The wheel-bug, Prionidus ciistatus, in all its stages; natural size.

numbers. Taking it altogether, we find in this family mainly
forms that are beneficial to the farmer.

There are a few other common species, also predaceous in
character, but much smaller and more slender than the pre-
ceding, belonging to the family Nabidce. Our common species
of the genera Nabis and Coriscus are yellowish in color, flat-
tened above and rather roughened, with long legs, but other-
wise resembling in head and beak the usual predaceous form,
except that the beak is longer and more slender. They are
found on flowers and leaves, preying upon almost anything that
they can conquer.

154

AN ECONOMIC ENTOMOLOGY.

A very curious, chunky little species, with the sides of the
abdomen much elevated, and the forelegs much broadened and
fitted for clasping, belongs to the genus Phymata and the family
PhymatidcB. It is yellow and brown in color, and has the habit

of placing itself in the centre of
Fig. 115. certain flowers, in such a manner

'^^ssit^ ^^^ as to seem a part of the flower

^^. ^ itself It is thus in position to seize

any unlucky insect that comes
within reach, and, although it is
scarcely a quarter of an inch in

Fig. 1x6.

Nabh/usca.

Phymata erosa.—a, b, adult, from above and
side; c, front leg; d. beak.

length, it is sufiiciendy powerful to hold and conquer even
honey-bees. Butterflies are frequently its victims, and it is one
of the oddest forms in this order.

We sometimes find on the under side of leaves of tree and
shrub, little whitish, flat creatures, with gauze-like, broad wing-
covers, and a broad, gauze-like expansion covering the thorax.
These belong to the family TingitidcPAW^S. are among the prettiest
species in the order. There is no difficulty in recognizing them
in the adult stage, by their lace-like or reticulated covering,
which is sometimes banded with brown or spotted. Beneath
this covering the insects are black or brown, and occasionally
they increase sufficiently to do some injury to the plants upon
which they feed. The adults usually live through the winter and
lay their eggs in spring ; but sometimes eggs are laid in fall, and
the insects winter in that stage. For shelter, fallen leaves are
usually employed, or the adults creep under loose bark scales or
into crevices, and we must again recommend winter work in clear-

THE INSECT WORLD.

155

Fig. 117.

ing uj) rubbish of all kinds, or plowing it under. Where this is
done there will be no necessity for active treatment in summer.
They may be destroyed at that time, however, by the application
of the kerosene emulsion diluted ten times, or by the whale-oil
soap used at the rate of one pound in four gallons of water.

Perhaps no insect is better known than the " bed-bug," Acan-
thia ledularia, which occurs, especially m hotels, throughout the
country. It is wingless, very much flattened, broadly oval in
shape, and red brown in color. It is
able to crawl into the narrowest crev-
ices, and no bedstead has yet been
made which does not afford it shelter.
It is nocturnal in habit, seeking its
prey at night and occasionally making
life miserable. Where a house be-
comes thoroughly infested, specimens
are found under baseboards, beneath
loose paper, in cracks in the plaster,
and in fact wherever there is an open-
ing large enough to insert the blade
of a thin knife. They multiply rapidly
and are able to do without food for a
considerable period. In houses that

have been long abandoned, bed-bugs of all sizes may sometimes
be found, perfectly transparent as if they had been always with •
out food. It is probable, therefore, that they are able to subsist
upon some substance other than human blood. Where they are
accidentally introduced into a house and confined to beds, there
is nothing better for use than kerosene or gasoline. It should be
liberally applied in joints, crevices, and wherever there is the
least 0[)ening, so as to reach the bottom before the material soaks
into the wood, A single thorough application of this kind
usually proves successful, although it would be better to renew it
a week afterward, to reach forms that have hatched from eggs
since the previous application ; for in my experience neither
kerosene nor gasoline destroys the eggs with certainty. Another
effective remedy is corrosive sublimate dissolved in alcohol, and
this ha^ the advantage of being more lasting, remaining effective
for some time after it is applied. It is, however, exceedingly

The bed-bug, Acanthia lectularta.

156 AN ECONOMIC ENTOMOLOGY.

poisonous, and must be used with that fact in mind. Professor
Comstock states that where, in traveUing, "one is forced to lodge
at places infested by these insects, or by fleas, protection from
them can be had by sprinkling a small quantity of pyrethrum
powder between the sheets of the bed on retiring. ' '

Rather closely allied to the bed-bug in structure, if not in habit,
are a number of very small, flat species, with fully developed
wing-covers, which are usually found on flowers, feeding upon yet
smaller insects and perhaps also on eggs. They belong to the
family Anthocorida;, and the most common is a minute black in-
sect with yellow-tipped wings, known as
Fic- 1^8. the "insidious flower-bug," Triphleps in-

sidiosus, credited with feeding among others
upon the insects in Phylloxera galls.

Now follow the Capsidce, containing a
long series of species softer in texture than
most of those heretofore described. They
are plant bugs par excelle^ice, found on
vegetation of all kinds, frequently in very
great numbers, and feeding upon their
juices. The wing- covers are soft and flex-
„,,,,^ ,. ., ible throughout, though thickened basally.

Triphleps tiistdtosiis, the o > o ^ j

" insidious flower-bug." They puncture leaf, twig, stem, or flower,
and, where these punctures have been
made, there is usually a drying of the tissue which interrupts the
nourishment of the plant and often causes injury. As a rule, the
species are green or yellowish in color, sometimes black speckled,
and occasionally with reddish markings. In form they vary,
being sometimes broadly oval, sometimes quite narrow. The
antennae are usually long and prominent, and the ' ' buggy' ' odor
is well developed. We have a number of species abundant
enough to be injurious, and the question of dealing with them is
sometimes complicated. The insects winter in different stages ;
often as an egg laid in twigs, as with the ' ' four-lined plant-bug, ' '
Pcecilocapsus lineatus, attacking among others currant and goose-
berry bushes. The appHcation of insecticides to kill plant-bugs
has been found unsatisfactory. They resist even the kerosene
emulsion quite strongly, and in order to kill adults it cannot be
diluted more than five times. Even agfainst immature forms a

THE INSECT WORLD.

157

very strong mixture is necessary, and not more than six or seven
parts of water can be added if a good effect is expected. In the
case of the four-lined bug already mentioned, the knowledge
that it lays its eggs near the tips of currant and other twigs
suggests a careful winter pruning, the cut twigs and branches to
be burnt, and in this way injury may be prevented during the
year following. This measure is successfully used where shrubby

Fic;. 119.

Pacilocapsus linealus, four-lined plant-bug, natural size and enlarged : also egg mass
in currant, and, at e, a single egg, greatly enlarged.

or woody plants are attacked ; but on succulent annuals, collect-
ing the insects in the morning, before they have become active,
by shaking them into some sort of receptacle, is the most satis-
factory method.

In the Cotton belt there was no more troublesome insect, some
years ago, than the "red-bug," or " cotton-stainer," Dysdercus
suturellus, so named from the fact that its excrement, voided in
the opening bolls, stained the cotton red, and thus caused it to
become of inferior value. Since cotton-seed has become almost
as valuable as the cotton itself, and is now completely used up,
it has been found that these insects have become practically harm-
less. It seems that they were enabled to multiply unduly in the
heaps of decaying cotton-seed, and since at present no such heaps
exist they cannot increase so rapidly. They also attack oranges
in Florida, and Professor Comstock recommends that they be

158

AN ECONOMIC ENTOMOLOGY.

trapped by placing small heaps of cotton-seed in the groves, to
attract them where they can be easily destroyed with pure kero-
sene.

Fig. 1 20.

Dysdercus suturelbts. — a, pupa; b, adult.

In the family LygtzidcB we have species that are oblong in
shape, rounded behind and flattened above. They have quite

long beaks, a moderate-
^^" ^^^' sized head, and all of

them are vegetable feed-
ers. The body is rather
hard, and the insects are
often brilliantly or gaudily
colored, black and red,
in the strongest possible
contrast, being favorite
combinations. Some be-
come nearly an inch in
length, though most of
them are much smaller.
The best known of the species is the "chinch-bug," Blissus
leiccoptems, less than one-fifth of an inch in length, blackish-

The chinch-bug, Blissus leucopterus ;
short-winged forms, enlarged

and

n-a-»KtiRTY OF

Z. p. METCALF

THE INSECT WORLD.

159

Fjg. 122.

f%

brown in color, and with soft white wing-covers, which make it
quite conspicuous. It feeds on grass crops of all kinds, in-
cluding grain and corn, and causes enormous injury annually.
It can hardly be said that we have any entirely satisfactory
means ol controlling this pest at the present time. Elaborate
experiments have been made in some of the Central States with
a fungous disease to which the insects are subject, but the out-
come has hardly equalled expectations. We know positively
that they hibernate in the adult stage, hidmg everywhere, and
appearing in spring to oviposit just beneath the soil upon roots,
or on stems at or above the surface. It is said that a single
female lays about five hundred eggs. The brood becomes adult
in midsummer, or thereabouts, and there is then a tendency
to migrate, particularly if the original infestation was in wheat,
which is by that time mature and does not suit them as food.
Corn or any other
grass crop in the
vicinity is then at-
tacked, though corn
is favored because
of its juiciness.
Elaborate publica-
tions on this insect
and the means for
its control have been
issued by the United
States Department
of Agriculture, and

by the Experiment Stations in Illinois, Kansas, and other States
in the grain and corn-raising districts of the country. The
recommendations generally narrow down to a thorough clear-
ing up in winter to destroy as far as may be the hibernating
adults. When the migrations commence from wheat to corn,
protection may often be obtained by trenching. The insects
do not readily resort to flight even when adult, but rather march
from field to field, and, by interposing a trench which is not
easily crossed, and where the insects can be destroyed by means
of tar or kerosene, fields may be protected. As this subject
is yet under consideration by so many students, it will not be

Chinch-bug.— a, 6, egg; r, newly-hatched larva; <?,/, larvae
further advanced; g, pupa; h, leg; i, beak ; 7, tarsus.

1 6c

AN ECONOMIC ENTOMOLOGY.

necessary to go into details here. The agriculturist in the regions
subject to chinch-bug attack should in each case inform himself
of what results have been reached, and what recommendations
are made by the Experiment Station in his own State. It need
only be added that the character of the weather frequently deter-
mines the increase of the insects, dry warm weather favoring,
and wet cold weather being unfavorable to their development.

In the family Coreidce we have species of moderate or large
size, many of them very curious in form and shape, some of them
carnivorous, but others vegetarian and more or less injurious.
They are oblong, rounded behind, the head rather small, with
long antennae, and a beak of moderate length. They are flat-
tened above, but very convex beneath, so that a section through
the insect would show an appearance nearly resembling an equi-
lateral triangle. The legs are usually of moderate length, but
sometimes become curiously enlarged, the hind legs especially
being subject to leaf-like expansions, giving the insects a decidedly
odd and bizarre appearance. They are brown in color, some-
times black-marked, sometimes with reddish variegations, and
altogether, perhaps, they resemble most nearly the Reduviidcs,
from which they are easily distinguished by the larger head and
the longer, flattened, four-jointed beak. All
the members of this family may be looked
upon with suspicion, because, although a
number of them do undoubtedly feed upon
other insects, yet some of these very pre-
daceous forms have also been observed feed-
ing upon plants, and it is more than likely
that they vary their diet as occasion serves.
A typical representative of the injurious
forms is the well-known "squash-bug,"
Anasa tristis, which attacks cucurbit vines
of all kinds and sometimes does notable
injury. The insect is dull grayish-brown in
color, the tips of the wing-covers darker,
while the edges are somewhat paler. It is
between one- half and three-fourths of an inch in length, quite a
ready flier, but with rather weak legs, and therefore a poor run-
ner. It is also called the "stink-bug," because of a peculiarly

Fig. 123.

The squasli-bug
tyisiis.

Aiiasa

THE INSECT WORLD. l6l

offensive musky odor, which is quite lasting and noticeable even
after stained hands have been thoroughly washed. We find the
adult late in fall, and it remains in that condition during the winter,
under bark of trees, under rubbish, in barns and similar localities.
A large number are destroyed by one cause or another during this
period, but some survive, and in the spring lay upon the squash
or other cucurbit vines patches of unusually large, almost golden-
brown eggs. The little fellows that hatch from them are much
shorter and broader in proportion than the adults, maturing some
time during midsummer, and providing thus for a second genera-
tion. Only two broods occur in the Middle States, though they
overlap somewhat, making it appear as if breeding continued
during the entire summer and early fall. The punctures made by
this insect in feeding seem to have a peculiarly poisonous effect
upon the plants, young vines especially being apt to succumb to
even a few specimens. This is another of the cases where clean-
liness becomes advantageous, and constitutes also a method of
avoiding injury to a great extent. It has been found that the
second brood does not mature until quite late in fall, and, seem-
ingly, only those that become adult after the beginning of Sep-
tember have any tendency to go into winter quarters. It should
be the object of every grower afflicted by these insects to destroy
the cucurbit vines just as soon as he has all the crop he wants from
them. This can be done by plowing under thoroughly, or by
raking out and burning the vines. In either case the immature
bugs starve to death and never develop into adults. If this practice
is followed by all growers, in localities where raising cucurbits is
an industry, there is little danger of trouble from the insects. In
kitchen gardens, and on a small scale, injury may be prevented
by first picking off the bugs wherever they are noticed and, later,
picking off those parts of the leaves containing eggs. The eggs
are laid on the under side, and are so prominent that looking for
them is a matter of little difficulty, no cluster escaping a more
than casual glance.

Now comes a series of broad, heavily-built bugs, in which the
scutellum is greatly elongated and covers a large part of the
abdomen. In this, the PentatomidcB , the enlarged scutellum is
triangular, and has a lateral groove into which the edges of the
wing-covers fit when not in use. Here also we have some species

II

l62

AN ECONOMIC ENTOMOLOGY.

that are predaceous and others that are plant-feeders, and, as in
the preceding case, it is difficult to say always whether the
species are beneficial or injurious. They will all stand watching,
at any rate, but, fortunately, not many of them occur in great
numbers. Perhaps the most marked exception is the ' ' harlequin
cabbage-bug," Murgantia histrionica. This is one of the most
serious pests to cabbage in the Southern States, being found in

small numbers on Long
Fig. 124. Island, in the southern part

of New Jersey, and then
increasing rapidly in num-
ber and destructiveness
throughout the South and
Southwest. These also win-
ter in the adult stage, and
egg-laying begins quite
early in the spring. They
are said to pass through all
their stages in two weeks,
and it can be readily seen
that there is room for a
number of generations in
the course of the season. Practical experiments seem to prove
that fighting the adults early in spring is most effective. Mus-
tard seems to be their favorite food-plant, and it is recommended
to plant rows of mustard between the cabbage rows for the pur-
pose of attracting the old bugs. They can be sprayed there
with pure kerosene, which kills them readily, and if it also kills
the mustard, no great harm is done ; or, they can be collected in
pans in the morning, before they have become active, and in this
way they will be sufficiently reduced in number to prevent them
from becoming troublesome later on. Of course this is another
of the remedies that depends for its greatest success upon com-
bined action. It has also been recommended that the hibernating
bugs be trapped in early spring under turnip or cabbage leaves,
preserved for that purpose during the winter.

The allied family Cydnidce is interesting, having the legs formed
for digging, though otherwise resembling the preceding. Their
food habits are not well known ; but none of them are mjurious.

/ 9

Harlequin cabbage-bug, Alurganlia hhlyion-
ica. — (7, b, larva and pupa ; c, d, e, eggs, natural
sizeand enlarged, from side and top ,/,g', adult.

THE INSECT WORLD. 163

A very curious series is the Corimelcenida, or "negro-bugs,"
distinct by their usually small size, their intense black colors,
which occasionally have a bluish or greenish
tinge, and by their very convex form. The
scutellum covers nearly the entire upper surface
of the botly, and the insects are quite generally
mistaken for small beetles. They may be found
on plants of all kinds and sometimes in consider-
able numbers, but noticeable injury is rarely in-
flicted. Their most disagreeable habit is laying Fiea-iike negro-
eggs on a number of the small fruits, like black- ^'f.' ^'^''"f^"^

^° _ ' ^;</;ca>ia, enlarged.

berry and raspberry, and if these are crushed

in eating, an excessively disagreeable, ' ' bed-buggy' ' taste is

noticed.

The last family of this order to which we call attention, even
though it is not injurious, is the ScutelleridcB, the species of
which are yet more oval, though perhaps less convex than the
preceding. As before, the scutellum covers nearly the whole
of the abdomen, but these species are often brightly colored.
They are moderate in size or quite large, and are southern and
western, a few species only being rarely found northward.

Taking it altogether we have in the heteropterous series of the
Hemiptera forms which gain their food by sucking juices, and in
perhaps the majority of instances the juices of plants. Yet,
taking it altogether, there are comparatively few seriously injuri-
ous species, and, if we except the "chinch-bug," they do not
begin to compare with their homopterous brethren in the amount
of injury they do to farm crops. The insects are nearly all diffi-
cult to deal with, as they resist insecticides quite strongly. No
weak mixtures affect them, and even the kerosene emulsion
cannot be diluted more than three or four times, if any large
proportion of adults are to be killed. Stomach poisons are out
of the question, of course, and we are thus reduced to mechani-
cal means or farm practice to avoid trouble. These methods
have been indicated in the course of the chapter, and need no
formal repetition.

164

AN ECONOMIC ENTOMOLOGY.

CHAPTER VI.

THE COLEOPTERA OR BEETLES.

Fig. 126.

The Coleoptera, "horn-winged" insects, or beetles, are dis-
tinguished by the hard, horny, or tough, leathery texture of the
fore-wings or elytra, which meet in a straight line down the
middle of the back, and are not used in flight, serving as wing-
covers only. They vary greatly, and are numerous in specimens
and species, over twelve thousand kinds having been described
from the United States and British America alone. They are as
diverse in habit as in size and form, some being among the most
dangerous enemies of agriculture, while others are among the
most useful.

It seems at first sight as if the recognition of beneficial or in-
jurious forms among so many would prove a hopeless task, and
yet we find it in most cases possible to say at a glance whether a
given specimen is herbivorous, i.e., plant-
feeding, or carnivo7'oiis, i.e., flesh-feeding
and predaceous.

All beetles are mandibulate and chew their
food ; but in one series the head is more or
less prolonged into a snout or beak, at the
end of which the much-reduced mouth parts
are situated. These are the Rhynchophora,
or "snout-beetles," all of which are plant-
feeders and injurious, or likely to prove so.
The true Coleoptera, in which the head is
h, normally four-jointed; not prolonged iuto a beak, wc Can separate
c four-jointed, with the | ^j^^ structure of the tarsi or feet. Nor-

third joint deeply lobed, ■'

from side and from above, mally there are fivc joiuts or segments to
each pair of feet ; but there are many de-
partures from this rule, one large series having four apparent
joints only, of which the third is lobed or deeply notched. The
species in which this structure obtains are all plant-feeders ;
either on leaves or in stems, trunks, branches, or roots ; often
in dead, though more usually in living tissue. In no other case

Tarsi in Coleoptera
a, normally five-jointed

THE INSECT WORLD. 1 65

is the structure df the tarsi alone an absolute guide to the food
habits ; but if we turn to the antennae or feelers we obtain an
additional basis.

Roughly speaking, the beetles, other than those already sepa-
rated off, may be divided into filicornia, or those in which the
antennae are more or less thread-like, and which are usually car-
nivorous ; clavicornia, in which they enlarge toward the tip or
terminate in a more or less marked club, which are rarely carniv-
orous and usually scavengers ; serricornia, where the joints are
somewhat flattened and widen toward the tip, so that one mar-
gin resembles to a greater or less degree the toothed edge of a
saw, which are feeders upon vegetation, as a rule ; lamelli-
cornia, in which there is a leaf-like club at tip, which are always
vegetable feeders ; and vio7iilicornia, where the joints are more
or less oval or globular and set so as to appear like a string of
beads.

The terms Jilicornia and vionilicornia are not in general use at
the present time. The latter series has the hind tarsi four-jointed
and the anterior and middle five-jointed, whence they are now
termed Heteromcra, or "different-jointed," to distinguish them
from the "' Isomera'' where all feet have the same number of
segments. But they are not uniform in habit, so that the deter-
mination of an insect as belonging to this heteromerous series
does not at once determine whether it is friend or foe. For the
Jilicornia the term Adephaga is used, from the usually predaceous
habits.

Following the usual order of systematic arrangement, a com-
prehensive statement of the differences is as follows :

I. Series with the head not prolonged into a snout, true Coleopter.a.

«, The antennae filiform, or thread-like, the tarsi with five joints on

all feet Adephaga.

b. The antennae thickening outwardly into a more or less well-formed

club, tarsi with an equal though varying number of joints on
all feet Clavicornia.

c, The antennae serrate or saw-toothed, the tarsi usually five-

jointed Serricornia.

d, The antennae with a lamellate or leaf-like club at tip, the tarsi

five-jointed Lamellicornia.

e. The antennae somewhat variable, the tarsi four-jointed, the third

deeply lobed or cleft Phvtophaga.

1 66 ^A' ECONOMIC ENTOMOLOGY.

', Theanteniice variable, though usually moniliform ; fore and middle

tarsi five-jointed, hind tarsi four-jointed .... Heteromera.

2. Series with the head prolonged into a more or less prominent snout,.

hence called snout-beetles or weevils Rhynchophora.

In the Adephaga there are many species of predaceous habit
in the larval as well as adult stage, of which a few more common
types may serve as examples.

The ' ' tiger-beetles, ' ' or Cicmdelidce ^ are moderately large,
very active and graceful species, that run rapidly and fly readily.
Most of them frequent sandy or open spaces, their colors often
matching their surroundings with marvellous accuracy. On the
seashore they are white, or gray with white hairs and lines, and
on the marshes or mud-flats the prevailing colors are dull mouse-
gray, without contrasting lines. Early in spring a bright-green
species is foimd at the margin of woods or in shaded lanes, promi-
nent on the bare ground for an instant, but lost to sight at once,
when startled, in a tuft of grass or on a moss-covered stone or
log.

The larvae are uncouth creatures, rarely seen unless sought for.
They make vertical burrows in sandy soil or along roads, and
there wait for passing prey, their round flat head closing the
opening completely, while their eyes are so set as to command
the near surroundings. They are humped posteriorly, and on
the hump curved spines are set, which may be forced into the
burrow wall to maintain a position at any height, and to resist
without effort any ordinary attempt to pull them out of their den.
Though these "tigers" are exceedingly voracious, they are of
little benefit to the agriculturist, because they do not frequent
cultivated fields or orchards.

The Carabidce, or "ground-beetles," run to black and brown
colors without prominent markings, and are usually more or less
flattened. They live under stones, sticks, leaves, or shelter of
any kind, in fields and along the edges of woods, more rarely in
the woods themselves, and sometimes under loose bark or even
among leaves. They are of a retiring disposition, and seldom
stir abroad until after dark, when the majority fly readily. Many
of them are attracted to light, and are recognizable, when they
strike the table or other flat surface, by the rapidity with which
they run, by their prominent mandibles, and slender, moderately-

Fig. T29.

Fig. 133.

Fig. 130.

Fig. 135.

A® ^Iml} j&

Fig. 134. Fig. 136.

Tiger-beetles and ground-beetles. — Fig. 127, larva of Ctctndela. Fig. 128, head of
Cicindela, to show mandible. Fig. 129, C. generosa. Fig. 130, C. purp7trea. Fig. 131,
C. sexgiittala. Fig. 132, C. rcpanda. Fig. 133, Calosoma cahditm and its larva. Fig. 134,
C. scrutator. Fig. 135, Brachiniis fumans. Fig. 12,6, Harpaliis caliginosus. Fig. 137,
larva of Harpalus, devouring larva of plum-curculio. Fig. 13S, Lebia grandis. All
except Fig. 135 about natural size.

167

1 68 AN ECONOMIC ENTOMOLOGY.

long antennae. Some of them are dirty clay-yellow in color, with
the disk of the wing-covers marked with black or brown.

We have only a few species belonging to the genera Carabus
and Calosoma, in marked contrast to the great number found in
European fields, none of our large forms having found life in
tilled land tolerable. The species of Calosoma often ascend trees
and feed on caterpillars, the term "caterpillar hunters" having
been in consequence applied to them ; but some of the smaller
species also have similar habits. In orchards they are sometimes
found hidden just beneath the surface of the soil, close to the base
of the trees.

The ' ' Bombardier beetles, ' ' belonging to the genus Brachinus,
may be especially mentioned because of their peculiar power of
emitting a puff of bluish vapor from the anus when suddenly dis-
turbed. They have the body, head, and thorax reddish, the
elytra blue, and are found under stones along the edges of roads
and near woodlands, or, more rarely, in the loose rubbish at the
base of trees.

A series of very much flattened species frequents flowers, feeding
upon the minute insects abundant there, and these are sometimes
red and blue, or even brilliant metallic green, with the wing-
covers squarely cut ofl behind so as to expose the tip of the
abdomen. Among these is the Lebia grandis, a moderate-sized
species, with yellowish-red head and thorax, and blue elytra, that
makes itself useful by feeding upon the eggs and larvae of the
Colorado potato-beetle.

But the great majority of our species are moderate in size, and
of powerful build, black or nearly so, lurking under all sorts of
rubbish in field and orchard, frequently in large numbers, yet
rarely observed, and ready at all times to pounce upon any soft-
bodied larvae that come within their range of vision. These
belong to the genera Pterostichus, Anisodactyhcs, Amara, Har-
palus, Agonodenis, or their close allies, and they are decidedly
important factors in checking the undue increase of certain species
which must go underground to complete their transformations,
— e.g.,\.\\e " plum-curculio," " pear-midge," and others.- Their
larvae are even more retiring and less frequently seen, but live
in similar situations. They are slender, more or less flattened,
of nearly equal width, with six short legs, a pair of prominent

THE INSECT WORLD.

169

mandibles, and a pair of bristly processes at the anal end of the
body.

Two other families belonj^ing to the Adephaga are aquatic in
the larval as well as adult stage, and are as predaceous as their
terrestrial relatives.

The Dytiscidce and ^^"'- ^^9-

their larvae have been
termed "water-
tigers," and the larger
species attack small
fish as well as insects.
In form they are oval
and somewhat flat-
tened, and they may
often be seen rising to
the surface of quiet
pools or spring-holes,
head down, releasing
a bubble of air, and
then, after remaining
for a little time, with

the anal extremity a water-tiger, ZJy/w^j wrtr^/wa/«. — a, larva, devour-

, , ^ ing an Agrion larva ; i, pupa ; c, male beetle, the elytra

aDOVe tne SUriace, of the female at side ; rf, anterior tarsus of the male, with

again starting for the sucking disks; e, tarsus of the female: a, b, c, about

t ^. rr^x • natural size.

bottom. 1 here is con-
siderable space between the wing-covers and the abdomen in
these species, and this is utilized as a reservoir for the air which
the insect breathes beneath the surface. When it becomes impure
the beetle rises again to the surface, releases the vitiated air, and
takes in a new supply.

This ends the series Adephaga^ and no practically injurious
forms exist in it ; all are more or less beneficial by reason of their
predaceous habits. Under some circumstances a few of the
species eat pollen, and after midsummer some have been found
gnawing grass-seed ; one or two species have even been found
eating into the kernels of corn, so there appears to be a tendency
to vary to a vegetable diet under certain conditions. In fact it
has been demonstrated that in many species some vegetable
matter is regularly eaten ; yet, as this feeding is not of a character

170

JiV ECONOMIC ENTOMOLOGY.

injurious to the agriculturist, the series may be, as a whole,
accounted beneficial.

In the Clavicornia we have a much greater diversity of form,
and many families, diftering widely in habit, and some of these are
economically important.

Fig. 140.

A water-scavenger, Hydrophilus triangularis. — a, llie larva ; b, male adult ; c, pupa ; d,
opened, and e, closed egg case ; y to i, enlarged structural details of the adult.

First, joining to the aquatic Adephaga there are two families
of aquatic Clavicornia, the Hydrophilidce. or " water-scavengers,"
and the Gyrinidce, or "whirligig-beetles."
The former resemble the water-tigers in
general appearance, but are more convex
above and more flattened below, usually with
brightly-polished wing-covers. The differ-
ence in the form of the antennae will easily
prevent confusing the families.

The Gyrinidce cannot be mistaken. They
are black or bronzed, oval, shining, with un-
usually long forelegs, and disport themselves
ifhiriigig-'-beetie i" swamis OH the surfacc of ponds and streams,
(1) and its larva (2): nat- darting here and there, or sometimes swim-

ural size. • • 11 • 1 11 1

ming rapidly in large or small, regular or
irregular circles, whence they derive their "whirligig" appella-
tion. They are predaceous in all stages, but of no agricultural
value from their strictly aquatic habits.

rilK IXSECT WORLD.

171

The family Si7p/iiiia\ containing what are popularly known as
"carrion" and "burying beetles," is in sharp contrast to any-
thing heretofore spoken of, and here the antennce are capitate, —
i.e., terminated by a spherical or ovate knob abruptly formed,
like a head. The beetles are usually found on or about carrion
of all kinds, though some of the smaller forms live in decaying
fungi. In the large species there are two distinct types, repre-
sented on the one hand by the genus Silpha, in which the species

Fig. 142.

Carrion beetles. — a, Necrophorus americana ; b, larva oi Silpha lapponica ; c, Silpka

americana.

are much flattened and proportionately very broad, with small
heads, and on the other by the genus Necrophorus, in which the
species are much more heavily built, narrower, not flattened, and
with large heads. These are the true "burying" beetles, and
derive the name from their habit of excavating beneath small
dead animals and gradually sinking them below the surface level.
Then the females lay their eggs in and the larvae live upon the
buried and decaying creatures. The other carrion beetles make
no pretence of burying their prey, but lay their eggs at once,
and the larvae feed upon it from below, usually making a short
burrow in the soil for shelter, though this is not universal. In
both types the larvae are black, flattened, broadly oval, and with

172

AN ECONOMIC ENTOMOLOGY.

Fig. 143.

Rove-beetle and its larva.

the segments distinctly marked at the edges. These beetles have
the sense of smell wonderfully developed, and I have frequently
covered a small, freshly-killed animal with a box of wood or
tin, only to find next morning a number of the insects beneath
it. The species are generally nocturnal, and as scavengers are
useful, or at least innoxious.

The large series of "rove-beetles," or Staphylinidce, is pecu-
liar in the short wing-covers, which leave more than half the
abdomen exposed. The species are always
long and comparatively narrow, usually
with a large head and well-developed man-
dibles, and live in all sorts of fermenting,
^ decaying, or excrementitious animal or
vegetable matter. Most of them are small,
and many are found beneath bark, in fer-
menting sap, or in fungi, while the larger
forms are often found in or under animal
excrement, or on or under carrion. In
short, the species are scavengers, with a
tendency to a predatory habit in some cases, and never any
disposition to feed upon growing vegetation. They may thus be
accounted either actively beneficial or at least not injurious, and
as scavengers they aid in reducing organic matter into condition
for assimilation by plant-life.

The next family meriting attention from its economic interest
is the Coccinellidce, or, as the species are commonly termed,
"lady-bugs" or "lady-birds." Scientifically these insects are
distinguished by having the tarsi three-jointed only ; but practi-
cally they are recognizable by their oval or round form, — always
convex, sometimes almost hemispherical, — and by their colors,
which are either of some shade of red with black spots and
markings, or black, with red or yellow spots. The species are
never large, sometimes very small ; but in almost all cases are
predaceous, their prey consisting chiefly of plant-lice or scale
insects. The larvae, which have the same feeding habits, are
usually fusiform, with a small head and quite long legs. They
are often prettily colored, sometimes with spiny warts or pro-
cesses, and may be seen running about wherever plant-lice
abound. Patches of from fifteen to forty of the yellow eggs

THE INSECT WORLD.

173

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174

AN ECONOMIC ENTOMOLOGY.

laid by the beetles are often seen in abundance on infested
plants.

The species of Mcgilla and Hippodamia are more oval and
less convex than usual, and some of them have been found feed-
ing on pollen or even seeds, when their natural prey was scarce ;
yet I have observed these same species doing yeoman's work in
the destruction of plant-lice on melon-vines.

The generai Ada/ia and Coccinella contain the more hemispher-
ical types, and among the most common are the " 9-spotted lady-
bird," Coccinella g-?iotata, which is one of the larger species, and
the " 2-spotted lady-bird," Adalia bipzincta, which is the smaller
and perhaps most frequently seen in gardens and even houses.
Among the largest of our forms is the " 15-spotted lady-bird,"
Anatis i_^ -punctata, interesting from its color variations, ranging
from creamy-white with distinct black spots to uniform mahogany
brown.

Opening quite a distinct series of species, which are black,
with red or yellow spots, is the " twice-stabbed" lady-bird, Chilo-
coriis bivulnerus, in which the larva is spiny. This is black,
almost hemispherical, with a somewhat ovate red spot on each
wing-cover, and is found throughout the United States. Its
chief food, in the larval as well as the adult stage, consists of scale
insects, and it is one of the most effective checks on that kind of
plant pest, under favorable circumstances ridding individual trees
completely.

We have other similar but smaller species, sometimes with
numerous yellow spots on the wing-covers, and most of them
have the scale-eating habit to a greater or less extent. The
species of Peiitilia are uniformly black and very small, less in
size than most of the scale insects upon which they prey ; but
they, as well as their minute spiny larvae, are great feeders, espe-
cially upon the eggs and larvae. The destructive San Jose scale
has no more persistent or effective enemy than this kind of small
lady-bird.

The species of Scymnns are also small, usually recognizable by
their fine pubescent or hairy clothing and black colors. There
is a tendency to red-tipped wing-covers or red thorax, and these
forms also prey largely upon scales. To this family belong the
Australian species of Vedalia, Orciis, and Rhizobius, introduced

THE INSECT WORLD.

175

Fig. 150.

to destroy the also imported "cottony cushion-scale," leery a
piirchasi. The relation of these species has been already dis-
cussed when speaking of the scale,
and will be again referred to in Part
III. of this work.

There are few rules without excep-
tions, and so we find sinners among
the lady-birds also, — all belonging to
the genus Epilachne. The species
are large, hemispherical, and yellow,
with black spots. The larvae are
also yellow, elongate oval, with long
branched spines. E. borealis is the
Northern and Eastern species at-
tacking cucumber, melon, and sim-
ilar vines, while E. comipta is found
in the West and Southwest, injuring
beans. A curious feature in E. borealis
is the manner in which the adult
marks out a circle at the edge of a
leaf and feeds within it until all usable
tissue is exhausted, before proceeding
to another place to repeat the opera-
tion.

As these injurious species feed
openly in all stages, they can be
reached without trouble by any of the
arsenites.

The family Erotylida; contains some
very prettily marked species of quite
diverse forms, most of which feed in
or on fungi, or may be found under
loose bark, and are, therefore, innox-
ious. In the genus Languria, how-
ever, we find an exception, since their
larvae live in the stems of clover and
other plants. They are very slender,
almost cylindrical, from one-fourth to
one-half an inch in length, and have the wing-covers blue or

Epilachne comipta. — A, adult ;
B, pupa; C, larva; 1), injury on
bean.

176

AN ECONOMIC ENTOMOLOGY.

black, while the thorax is usually more or less red or yellow.
Our common clover-feeding species is L. mozardi. It is rarely
that any species becomes abundant enough to do noticeable in-

FiG. 151.

Languria mozardi. — n, egg ; b, larva in clover stem ; c, larva ; d, pupa ; e, adult.

jury ; but in clover, if a sufficiently large infested area occurs,
prompt close cutting or turning under the sod will be most
effective in checking present and preventing future injury.

The Cucujidcz are elongate and very much flattened beetles,
fitted to live under bark of trees or in the narrow crevices where

Silvanus surinatnensis . — a, beetle ; b, pupa ; c, larva.

they are usually found. Some of the species of Silvanus, notably
6^. siirinamensis, a brown species, hardly more than one-eighth

THE INSECT WORLD.

177

inch in length, with the edges of the thorax toothed, are excep-
tions in habit, though not in form, and often infest granaries,
mills, and stables. The adult as well as its larva is frequently-
found in mangers or in neglected little masses of meal, flour, or
grain, in which they breed. Cleanliness is the best remedy when
these insects become abundant : allow no partly emptied boxes
or bags to lie about, keep current supplies covered or tied up,
and sweep out corners at short intervals. Bisulphide of carbon,
where its apjilication is possible, is an effective remedy, readily-
destroying the beetles as well as their larvae.

Fig. 153.

Fig. 154.

Fig. 155.

Atomaria cphippiata.

Cotticaria pumila.

Cryptophagtis croccus.

There are other, yet smaller beetles found in similar situations
in less numbers, and these belong to allied families. They may-
be brown, not more than one-sixteenth of an inch in length, with
an oval body and narrow thorax, and then they are probably
species of Corticaria ; they may be of similar color, but with the
thorax and body more nearly of a width, and then they may
belong io Ato)fiaria or Cryptophagiis ; or they may be equally
minute but flattened, black, with red or yellow spots or bands on
the elytra, and then they probably belong to Litargus. All may
be treated as above suggested.

We have a series of robust, small or moderate- sized beetles,
usually broad but sometimes narrowly oval, with small retracted
head, slender, moderately long legs, capable of being so closely
folded upon the breast as to be almost invisible, and with the
unpleasant habit of feeding upon dried animal substances, such
as furs, skins, woollens, museum specimens, meats, and the like.

12

178

AN ECONOMIC ENTOH/OLOGY.

Fig. 156.

The larder-beetle, Dermes-
tes lardariiis. — a, la'rva ; b, a
single hair from larva ; c, adult
beetle.

These belong to the family Dermcstidce, which contains such
nuisances as the "larder-beetles," "carpet-beetles," and "mu-
seum-beetles." The elytra, which cover
the abdomen completely, are black or
gray, usually ornamented with white or
colored scales, which sometimes form
quite pretty markings.

The "larder-beetle," or "bacon-
beetle," Dermcstes lardarms, is rather
more than one-fourth of an inch long,
and easily recognizable by having the
anterior half of the wing-covers pale
brown or yellowish, its livery else being
of a sombre black or dark gray. The
larva is nearly half an inch in length,
rather narrow yet plump, and clothed
with rather dense, long, brown hairs.
It feeds on stored provisions of all
kinds, on hides, skins, or other similar substances, and is occa-
sionally quite troublesome in smoke-houses. Cleanliness, plenty
of air, tight receptacles, and close-meshed wire netting on the

covers or doors of
Fig. 157. pantries and boxes

are the best prevent
ives, supplemented
by destruction of the
beetles and larvae
where^'er noticed.
Good results are
often obtained by
leaving a tempting
bit in an exposed
position, which will
act as a trap, attract-
ing beetles and larvae
where they can be
easily found and destroyed. Several other species, similar in
size but differently marked, have similar habits, and among
them the "leather-beetle," D. znilpiiius, has been responsible

Leather-beetle, Dei'mestrs Tul/>injis. — (7, Iar\ a ; //, pupa ;
k, adult ; (/ to /, details of larva.

THE INSECT WORLD.

179

for much mischief in tanneries and factories producing leather
goods. Where fumigation is possible, bisulphide of carbon may
be employed with good effect, while gasoline readily destroys
both beetles and larvae where it can be brought into contact with
them.

Larvae similar to those above described, but much smaller, are
often found in museum collections on mounted animals, eating
the skins, hair, and feathers, and in entomological collections,
destroying the specimens entirely. The beetles from these
larvae are smaller and more ovate, and belong to the genera
Trogodcnna or Megatoma. They are often found on flowers

Fig. 158.

The carpet-beetle, AnUwenus scrophtilaria . — a, larva; b, larval skin split to expose
the pupa within it ; c, pupa; d, beetle.

in this stage, in company with species of Anthrcnus, in which
the larvae are stouter, more clumsy, equally clothed with hairs,
but with the ability to expand two larger tufts posteriorly.
Ajithrenus also contains museum pests as well as the "carpet-
beetle," A. scropliularia, which feeds on woollens in the larval
condition, and is then better known as the " buffalo-moth," from
its tufted appearance. The beetles are very broadly oval, with
brick-red scales along the middle of the wing-covers, and two
irregular white scaly bands transversely across the elytra. I have
found them very early in sj)ring under the loose bark of trees
where they had passed the winter. Later they fly into open
windows, and lay their eggs wherever they And a supply of

l8o AN ECONOMIC ENTOMOLOGY.

woollens. For this household pest a liberal use of napthaline in
crystals or balls, in trunks and closets, is advisable as a pre-
ventive. Where woollen garments are to be stored through
the summer they should be first thoroughly beaten or brushed
and sunned out, then wrapped in stout paper with the edges
pasted, or in cotton sheeting well sewed. Then, if laid away
in boxes or trunks, or hung in closets with napthaline crystals
between the layers, or on the shelves, or among the bundles,
little danger is to be feared. Where carpets are infested, it is
best to have them taken up, thoroughly beaten and cleaned, and
the floors thoroughly cleansed before they are relaid. Where
this is undesirable for any reason, gasoline may be used with
satisfactory results. Except on the cheapest fabrics it may be
safely used in liberal quantities without danger of injuring either
texture or colors, and wherever the liquid comes into contact
with either beetle or larva it kills at once. Eggs, however, are
not destroyed, and close watch must be kept for a week at least,
when a second application may be found necessary to reach the
larvae hatched since the first was made. Another method,
almost equally good but more troublesome, is to place a wet
cloth over the infested patches and press over it with a very hot
flat-iron, the object being to drive hot steam or vapor through
the fabric and thus, practically, to cook the insects. In collec-
tions, tight boxes or cases and a free use of napthaline or
bisulphide of carbon, or both, are essential.

Unity of habit in this family is marred by Byturus zinicolor,
a little yellowish species which is densely covered with short silky
hair, and feeds in the blossoms of the red rasp-
FiG. 159. berry, where also its eggs are laid. The larvae
are white, nearly naked, and are found on the
inside of the berry when picked. The species has
not become seriously troublesome as yet, and is
mentioned here chiefly because of its unique
habits.

Bvluriis ttnicolor, rj-.] tt- 1 • j 11 1 1 • •

' ^j^j^^ ^ Ine Jriistertace are small, oval, slimmg, very

hard, black, bronzed or greenish beetles, with the

wing-covers cut oft' squarely behind, leaving the last segments

of the abdomen exposed. The legs are broad and flat, fitted for

digging, and the head is small, yet with quite prominent sharp

'J UK INSECT WORLD.

I8l

mandibles and capitate antennae. They are mostly scavengers,
the larvcTp white and somewhat maggot-like, occurring on, in, or
under all sorts oi excrcmcntitious or decaying animal or vegetable

I'IG. l6(>

Fig. 162.

Hister atcuatus ami Hister bimacjilatus , much enlarged.

matter, in over-ripe fungi or fruit, or under the loose bark of
trees. They are of no practical importance to the agriculturist.

The Nitidu/idce, or " sap-beetles," are also small, more or less
flattened, always with the tip of the abdomen exposed beyond the
wing-covers, and with the
legs not specialized for
digging purposes. They
feed in all stages on de-
caying or fermenting sap
or fruits or in fungi, and
some of them are found
also on carrion. As a
whole, while the species
are quite numerously rep-
resented and often seen,
yet they are not either markedly beneficial or injurious.

Somewhat similar habits are met with in the Trogositidcs,
which are also flattened creatures, most of them living under
bark. Some of the species of Tenebrioides, however, — black
beetles about one-fourth of an inch in length, with square thorax
and large head, known as " cadelles" — are found in .stables,
barns, and mills, feeding on grain, meal, and flour. They are

Carpophilus hemipterus,
enlarafed.

Ips fasciatus and its
larva, enlarged.

l82

AA ECONOMIC ENTOMOLOGY.

rarely very numerous, and may be kept in check as recom-
mended on a previous page for the Ctuujida:.

There are other small families in the clavicorn series, some of
them interesting enough to the entomologist, but none of im-
portance economically

Fig. 163.

Tenebrioides corticalis, the "cadelle." — a, larva; b,
adult ; c to/, structural details.

or likely to attract the
attention of the cas-

n\ 'C\^ Wm\ \J^^^^|L^/ sl-^^^^^A^^ "^^ observer; hence
C-J""Xl 'i^^'- l.^^'^J T ,V\ r J hardly subjects for de-
scription here.

The Serricornia, or
"saw-horned" series,
begins with the family
DascyllidcE, contain-
ing mostly small forms
found on dead or dy-
ing trees or branches,
in which the larvae probably live. None are of economic im-
portance, a fact which is also true of the next family, Rhipiceridce.
This latter, indeed, contains only five species, all accounted
rarities in collections, and believed to breed in cedars.

The family -£■/«/<? nV/.^, " spring- beetles," "click-beetles," or
" snapping-beetles, " contains numerous troublesome forms, and
is easily distinguishable in all its stages. The beetles have the
prothorax very loosely jointed to the rest of the body, and on

the under side a curved
^^" ^ ^' process fits into a cavity

of the meso-thorax.
When a specimen is
placed on its back it
bends the extremities so
as to raise the middle of
the body from the surface, and to bring the tip of the curved
process to the edge of the cavity. A sudden release of muscular
tension reverses matters, sends the insect into the air a few inches,
and this "snapping" or jumping performance is repeated until
it alights on its feet. In the larval stage the term " wire-worms"
expresses the appearance and texture of the creature, and brings
to mind at once an agent of destruction hardly surpassed in the

An Elater from side, to show t lie proslernal process.

THE LXSECT WORLD.

^83

insect world. Scarcely a farmer can be found who has not been
troubled to some extent by "wire-worms," and many a remedy
recommended as infallible has been tried and found wanting in
actual practice. We have two series of species, one of which

Fk;. 165.

Fk;. 166.

\'\c.. 167.

Fig. 105, tlie eyed Elater, Alatts ocitlatus. Fig. 160, wood-boring wire-worm, from side-
Fig. 167, a, larva; b, adult click-beetle.

feeds in decaying wood, the other underground on the roots of
plants ; of these the first may be left out of consideration alto-
gether, though in it may be found the species of Alans, our
largest and most prominent forms. The history of the subterra-
nean species is in general as follows : The beetles appear quite
early in spring, and may be noticed in fields where a sod has
been turned down, during the first days of May, or earlier in the
Southern States. They fly quite rapidly in mid-day, copulate,
and later seek a place to oviposit. During May or June, earlier
or later, according to the species, the eggs are laid in grass-land
or where there are plenty of weeds, — in other words, wherever
vegetation, especially of a grassy character, is abundant. The
larvae hatch by midsummer and feed upon roots, growing but
slowly and requiring, indeed, in many cases, two or three years
to complete their development. Pupation takes place in fall, and
usually the change to the adult also takes place before winter sets
in, though they remain quiet, and do not voluntarily emerge
until the spring following.

This brief sketch does not apply in its entirety to all the sub-
terranean forms even, but it applies very well to the majority

1 84 AN ECONOMIC ENTOMOLOGY.

of the injurious species. The noteworthy points are the early
appearance and oviposition of the beetles, the two- or three-year
life of the larva, and the pupation and change to adult in fall ;
all of which must be considered in the methods of treatment to
be adopted.
— The direct application of insecticides is usually impracticable,
and the texture of the larva is so dense that most contact poisons
are of little or no avail, salt in large quantity having proved the
most effective. Stomach poisons are not easily applied, but on
an experimental scale it has been found that sweetened dough
placed beneath the surface attracts them, and this can be poi-
soned and used as a trap. Practically, methods of cultivation
calculated to avoid injury are most satisfactory. Grass land
known to be infested should be plowed in fall, and while this will
not destroy any large proportion of the larvae, it will kill most of
the pupae and beetles then in the ground, so if the practice be
continued for a series of years the insects will be gradually run
out. Wherever feasible, crimson clover should be used as a
sod crop, as this is sown in late summer after the beetles have
oviposited and may be harvested and plowed under shortly after
the beetles have laid eggs, practically preventing the develop-
ment of the larvae, especially if a crop little or not at all subject
to wire-worms follows the clover. In fact, frequent change of
crops is a most satisfactory measure if the land be not allowed to
remain in grass more than one year, and if corn or potatoes do
not directly follow the sod. In light soil the salty fertilizers ex-
ercise a very beneficial effect when properly applied, and some-
times an advantage may be gained by keeping the land in sod as
llong as possible, where grass is needed as a crop. When it has
" run out," plow in fall ; in spring, after cultivating and prepar-
ing for the new crop, fertilize heavily, using kainit for potash and
nitrate of soda, so far as possible, for nitrogen. At least one
thousand pounds of kainit per acre should be used, and this
seems exceedingly disagreeable to the insects at all ages, and
fatal to the younger forms. Conditions vary so much in different
parts of the country, and rotations are so diverse in character,
that it is impossible to suggest any course that will be universally
applicable, except the fall plowing. The suggestions above made
should be sufficient, however, to guide the intelligent farmer in

THE INSECT WORLD.

185

Fig. 16S.

adopting the practice best suited to secure exemption in his case.
It may be added, however, that the fertiHzers will not prove satis-
factory unless applied as directed, — i.e., in one heavy application
and when the ground is bare.

The species of the family lUipreslidcc resemble the click-
beetles in general form, but theprothorax is firmly articulated to
the rest of the body, so that the insects have no "springing"
powers, and the colors are metallic. The beetles vary much in
appearance, but the lar\'ie resemble each other closely, being
always flattened in form, with greatly enlarged anterior segments.
They are usually known as " flat-headed borers," sometimes as
" hammer-heads," and infest not only trees but shrubs, vines, and
sometimes even herbaceous plants. Some of the species prefer
dead or dying wood, some attack healthy plants
only, while others, and perhaps the majority, are
somewhat indifferent, yet are oftener found in
weak than in healthy and vigorous trees.

Our largest Eastern species belong to the
genus Chalcophora, the larvae mostly feeding on
conifers, though two of them feed on deciduous
trees like the sycamore. The beetles have the
elytra quite deeply and irregularly furrowed, while
the colors are bronze, brown, or blackish. I have
found the larvae in quite old and decaying logs, but they are said
to attack healthy trees as well, and to cause occasional injury.

The genus Dicerca contains robust species, sometimes nar-
rowing so strongly toward the tip as to seem almost tailed
wing-covers are decidedly convex, irregularly corru-
gated, or even reticulated, with elevated spots, and
the colors are bright bronze-brown, often with green-
ish or brassy reflections. They are rarely common,
but infest a variety of trees, among them peach,
plum, apricot, cherry, hickory, oak, and pine.

The genus Biiprestis contains flattened species
with even striae or ridges, and they are often of a
brilliant blue, green, or golden metallic color, occa-
sionally spotted and banded with yellow or brown.
The larvae feed mostly in conifers, but some also infest deciduous
trees, none thus far in dangerous numbers. In Melanophila the

Chalcophora vir-
giniensis.

The

Diccica di-
vai icatiX.

1 86

AN ECONOMIC ENTOMOLOGY.

Fig. 170.

The flat-head apple-borer
Chrysobothris femorata. — a
larva; ^, pupa ; rf, adult.

wing- covers are nearly smooth or with fine punctulations only,
and the larvae also feed principally in conifers.

In the genus Chrysobothris we have forms that are quite flat-
tened above, the wing-covers with irregular depressions and
elevations, the prothorax with curved
sides and narrower behind. Here be-
long most of the troublesome species,
including C. femorata, the ' ' flat-headed
apple-borer," which, despite its com-
mon name, attacks a great variety of
trees. The larva makes irregular chan-
nels and chambers in the sap-wood,
boring into the solid tissues a short dis-
tance only, just before pupation, and
this describes also the habits of many
of the other species of this genus. The
eggs are laid on the bark in June or
July, and the larvae hve from one to
three years before coming to maturity.
Pupation occurs shortly before the pe-
riod at which the adults emerge.

The genus Agriliis contains species differing from any of those
heretofore mentioned by their slender, cylindrical form, the head
squarely truncate, or cut off" in front, the elytra much narrowed
at tip. As a rule, the species are dull
brownish-bronze in color, the prothorax
sometimes brassy or red-bronzed, and
none is better known than the ' ' red-
necked blackberry-borer," Agrilus rufi-
collis, the author of the "gouty gall" on
that plant. The larvae in this genus are
unusually long and flattened, the seg-
ments strongly marked, the ' ' head' ' not
much wider than the body, and the anal
foi^ks distinct, differing in each species.
Returning to the blackberry-borer, it is
good practice to cut out all galled canes early in spring and burn
them. Trimming is done at this time as a matter of regular
cultivation, and the galls are then easily seen. No "galled"

Fig. 171.

Blackberry - cane
Agrilus ruficollis. — b
c, adult.

borer,
larva ;

THE INSECT WORLD.

187

cane ever ripens a fair set of berries, and it might as well be cut
out at once. Another satisfactory method is to cut off all the
new shoots at the surface of the ground about the end of June.
At this time all the beetles have laid their eggs, and the shoots
which come up in July cannot become infested. The best results
will be obtained by combining both methods. Cutting the new

Fig. 172.

-XZ.

Blackberry-gall maker.— a, gall just beginning to form over recent borings ; *, section
through an old stem to show the character of the gall.

shoots causes the death of the young larvae, which are unable to
subsist on dead wood, and being footless are unable to migrate
to new stalks.

Another species of Agrihcs seriously injurious in parts of the
Eastern United States is the "sinuate pear-borer," A. sinuatus,
imported from Europe within recent years. This feeds between
bark and wood in pear-trees, making immensely long zig-zag
galleries, finally girdling the tree and killing it. It lives two
years in the larval stage.

In general we are very helpless against boring larvae once they
get into the trunk of a tree. Cutting out is a tedious process,
even if the location of the larva is easily discoverable, which it
often is not. We must, therefore, try to prevent their entrance,

1 88 ^^V ECONOMIC ENTOMOLOGY.

and this may be done more or less completely by mechanical
means. As against the larger species — i.e., against all except
Agrilus — a wire mosquito netting loosely encircling the trunk, so
as not to touch it anywhere, is a complete protection. The in-
sects lay their eggs under a bark scale, or on smooth bark gnaw
a little hole in which the ^^^ is laid, and if access to the bark be
prevented they seek other localities. The wire must be tied at

Fig. 173.

The sinuate pear-borer, Agrilus sitiuatus. — a, beetle ; b, larva ; c, its anal fork ; d,
pupal chamber with pupa in position.

the top to prevent beetles getting under it, and must extend
underground an inch or so. In this way we not only prevent
new infestation, but any beetles that may emerge from the trunk
will be hopelessly imprisoned and will die without a chance to
reproduce.

Instead of wire netting, tarred paper or even newspapers
tightly wrapped around the trunk to the branches will answer
an excellent purpose, needing renewal each year, however, where
the wire netting lasts several seasons. Thorough whitewashing

THE INSECT WOKf.n. 189

offers a large measure of protection, since the adults will not vol-
untarily eat through a coat of it, and the larvae cannot do so

Fig. 174.

Work of tlif sinuate pear-lxini- 011 a Uartlett pear-tree : about one-fourth natural size.

when first they emerge from the ^%'g. The whitewash can be

igo

AX ECONOMIC ENTOMOLOGY.

applied with a knapsack pump through a Vermorel nozzle, and
a little Paris green adds greatly to its effectiveness. It should
be renewed every week or two until the middle of July, when the
danger from these flat-headed borers may be considered at an
end, and it has the advantage of protecting the branches as well
as the trunk. The admixture of a little glue or salt will improve
its adhesive and lasting qualities.

A strong fish-oil soap, say one pound in one gallon of water,
is also effective and may be applied in the same manner. It
forms a film of soap over the bark, and is repellent to the beetles
as well as fatal to the young larvae. The admixture of an ounce
of crude carbolic acid to a gallon of suds is advantageous. This
mixture should not be applied to leaves or on young shoots,
as it would probably cause injury. As these methods are all
preventive rather than remedial, they must be promptly and
thoroughly applied, and success will be in proportion to the
thoroughness with which the work is done. Instead of any of
the preceding methods, "insect lime" or " dendrolene " may
be with proper precautions employed on the trunks and larger
branches, and, practically, this is the best material for use against
the "sinuate pear-borer." It can be easily applied, remains
effective for weeks, and one application, properly made at the
right time, will protect the trees for the season. As against the
pear-borer, it should be applied not later than May 15th, and

kept intact until June
Fig. 175. 15th, when all danger

from that pest is over.
Reference should be
made to the chapters
on insecticides and
preventives for further
details as to applica-
tions.

In the next series,
the Lainpyridce, there
are no species injurious to vegetation, though, under the name
"fire-flies," some of them are well known. The beetles are
usually slender, somewhat flattened above, with a more or less
retracted head, and are of a soft leathery texture. The ' ' fire-

Fire-fly, Photinus pyralis. — cr, larva; *, pupa in cell
c, adult ; diof, structural details of larva.

THE INSECT IVORf.D.

191

Fig. 176.

flies " are first noticed in June in the more northern and central
portions of tlie United States, and have the terminal segments
of the abdomen on the under side of a bright sulphur-yellow
color, which at the will of tlie insect glows with a phosphorescent
light of considerable illuminating power. They hide during the
day on the foliage of plants or in crevices, and begin their flight
with the deepening of the twilight. In some species the female
is without wings and remains on the ground among the grass —
the "glow-worm." The larva- are predaccous, and some of
them live on snails.

Belonging to the same family, but of a diurnal habit and with-
out the illuminating power, are the "soldier-beetles," belonging
to the genera Chaiiliogna-
thus and Tclcphonis, dis-
tinguished also by having
a more prominent head
and large, round eyes.
These may be found on
flowers, where they prob-
ably feed on pollen, but
are of direct benefit by
aiding in pollination. The
larvae are even more de-
cidedly useful, being predaceous and feeding largely on soft-
bodied grubs and the like. They are long and slender, flattened
above and somewhat narrowed at each end, or fusiform, the
edges of the segments quite prominently marked. They are
especially effective against such creatures as the larvae of the plum
curculio when they enter the ground to pupate, and a large pro-
portion are thus disposed of annual!}-.

The species belonging to the family Malachiid(£ resemble the
Lampyrids in the soft body texture and leathery wing-covers,
but they are much shorter and broader, the broadest part of the
body coming near the end of the wing-covers. The antennae
are short, a little enlarged at the tip, and often curiously
knotted in the male. Many of the species have soft, orange-
colored vesicles, capable of being protruded from the side of
the body. They are usually found on flowers and feed on other
insects or insect eggs, probably doing much good in this way.

Soldier-beetle, Cliaitliogtuitlius pennsylvanicus.
— a, larva; b, its head enlarged; c to A, struc-
tural details; /, beetle, natural size.

19:

A.V ECONOMIC ENTOMOLOGY.

The larvae of only a few species are known, and these are pre-
daceous.

Next come the CleridcB, many of which are also flower-beetles,
but with longer legs, more prominently enlarged antennae, more

slender cylindrical form, and much
Fig. 177. firmer texture. They are bright

colored, as a rule, often prettily
banded, and sometimes quite abun-
dant. Many species are found on

Fig. 178.

Malachius marginicollis : much
enlarged.

Clef us apivorus. — a, larva ; b, pupa ;
beetle central : all enlarged.

the trunks of trees, running about rapidly and somewhat resem-
bling ants. Their larvae in such cases prey upon wood-boring
insects, principally such as live in sap-wood, and they are slender,

with short legs and a
Fig. 179. prominent, somewhat

pointed head. They are
extremely useful in keep-
ing in check bark-beetles
and other borers, and are
thus worthy of our dis-
tinguished consideration.
Most of the other species
are also predaceous in
the larval stage, but
hardly beneficial, since they live in the nests of bees, devouring
both the larvae and the food stored for them. Clenis apivorus

Red-legged ham-beetle, Coryuetcs rufipes.— a,
larva; 6, pupa ; c, cocoon ; d, e, beetle, enlarged
and natural size ; /toj, structural details.

THE IXSKCT WORLD.

193

infests the hives of the common honey-bee, and is more or less
of a nuisance in some locahties.

The ahiiost inevitable exception occurs in this family also, and
the species of Coryuetes, blue or part blue and part orange in
color, live upon dead or dry animal matter, often attacking pro-
visions. The "red-legged ham-beetle," C. 7'iifipes, is of this
type, and will serve to illustrate the series. The measures recom-
mended as against the Dcrmcstidce will answer here as well.

In the family PtinidcE we have an aggregation of oddities diffi-
cult of general definition, save that as a rule the species are
small, with retracted head, more or less cylindrical firm body, and
firm wing-covers. They feed in the larval as well as adult con-
dition on dry animal or vegetable matter, though some species
attack green vegetation. Many live in dead branches or twigs,
and only a few are of sufficient interest to be especially noted.
Of these is the "death-watch," Sitodrepa panicca, so named
from the ticking sound frequently made by the beetle when
working in wood, which superstition has interpreted as a warning
of approaching death. It works also in a great variety of other
substances, ranging from gunwads to roots of hellebore and old
books, as a fleshy, white, grub-like larva, with a brown head and
a surface covered with short, brown, bristle-like hairs. Where
the nature of the article admits of such treatment, exposure to
the fumes of bisulphide of carbon is a good remedy, as is also
saturating with gasoline or benzine. A liberal use of paint with
plenty of turpentine is indicated in other cases, and sometimes
mere cleanliness following the destruction of hopelessly infested
material will answer every purpose.

Of the same general shape, but larger and broader, with smooth
instead of striated wing-covers and a "humped" form, is the
Lasioderma serricorne, popularly known as the "tobacco-" or
" cigarette-beetle." It is a great lover of tobacco in all its forms,
the lar\'a relishing plug, long or fine cut, chewing or smoking, in
cigarette, cigar, or leaf, almost equally well, and injuring it
materially for the human user of the " weed." The matter is an
important one to manufacturers, who deal with it in a variety of
ways ; but it does not particularly interest the farmer.

Among the wood-feeders the species of Bostrychiis and Si7i-
oxylon are of interest, their larvae sometimes boring into fruit-trees.

13

Fig. I So.

Fig. 180, cigars injured by the tohacco-beolle, Lasioderma seryicorne ; holes show
where the beetles issued. Fig. 181, Lasioderma serricorne, from above and side.
Fig. 182, the " death-watch," Sitodrcpa panicea, larva and beetle, from above and side;
much enlarged.
194

THE JXSECr WORLD.

195

The " apple-twig borer," Amphicerus bicaudatus, is about the
only species needing especial remark, and this beetle bores into
small apple- twigs in early spring, entering close to a bud and
making a channel several inches in length, apparently for food
and shelter merely. It remains in these burrows a short time
only, and then lays its eggs in the dead or dying roots of " cat-

FiG. 183.

Apple-twig borer, Amphicrrus bicaudatus.— a, beetle, from above ; b, same, in outline, from
side ; d, larva ; g, pupa ; h, same in larval burrow ; c, e,/, structural details.

brier," or " greenbrier" {Smilax sp.), or in dead shoots of
grape. The insects rarely appear in troublesome numbers, and
then good practice is to look after neglected vineyards or grape
tangles in near-by woods, and after brier thickets, which latter
are an abomination at best and should be destroyed.

There are other Serricorn families, small both in size and in
the number of species they contain, but they are mostly rare, of
no economic importance, and need not be referred to here even
by name.

196

AiV ECONOMIC ENTOMOLOGY.

The next large series is the Lamellicomia, where the antennae
terminate in a lamellate or leaf- shaped club. All the species are
feeders upon vegetation, living or dead, green or in a stage of
decay, and in all cases the larvae are "white grubs," large or
small, smooth or hairy, but always " white grubs." These can
be generally described as having a large, yellow, or brown head,
with prominent mandibles and long palpi, legs that are quite long,
moderately stout, with distinct claws at the tip, usually also

Fig. I

Stag-beetles.— I, Lucaniis claphus, male; 2, L. dama, male.

clothed with hair, a body that is cylindrical, stout, wrinkled,
somewhat curved or even crescent-shaped, ending rather abruptly
in a more or less enlarged, obtuse, terminal bulb. As a rule,
the color is dirty yellowish white, but it may become pink,
greenish, or even blackish, the hinder portion always showing
darker because of the excrementitious mass which shows through
the transparent tissue.

Two families belong to this series, of which the Lucam'd^, or
stag-beetles, are of no economic importance though of much

THE IXSF.CT WORLD.

197

Fig. 1S5.

popular interest. They differ from the Scarabcrida; in that the
leaves of the club are separated and cannot be made to form
a solid club or mass.

Our most common " staj^-lK'etle" is the Lucanus dama, in
which the mandibles of the male are much enlarged and sickle-
shaped ; whence the common term " pinching-bug." It occurs
throughout the Mitldle and Central States, becoming more rare
to the North and losing interest in the South in favor of its more
prominent relative, the L. elaphus, which in the male has man-
dibles almost as long as itself, and branched like antlers, yielding
in this respect, however, to its European congener, the L. cervus,
or original "stag-beetle." Quite a different-looking creature is
the Passaliis cormdiis, perhaps the most common of all the
members of this family, though not always readily found. It is
coal-black, shining, with a large square thorax and a small head
armed with a short curved horn. All
these species and all the larvae of this
family feed in decaying wood, and
preferably in stumps or in roots. Thus
their function is rather as scavengers,
and never as destroyers of vegetable
life. The larva of the Passaliis cormitus
is interesting, because it has four legs
only, one pair being entirely aborted.

In the family Scarabczidce the leaves
of the antennal club are always close
together when at rest, but can be spread
out fan-like at the will of the insect,
exposing the numerous sensory pittings
with which they are closely set. The
legs are always fitted for digging.

At the beginning we meet a series of i^'^^'^aih
species that are scavengers, living on
decaying or excrementitious matter. Some of them are large
and have the curious habit of making balls of dung, in each of
which an ^^'g is laid. The balls are then buried beneath the
surface, and each furnishes sufficient food to bring one larva to
maturity. When the ball is made up on a road or other hard
surface, the insects roll it to some more suitable place, and have

AN ECONOMIC ENTOMOLOGY.

therefore received the popular name

Fig. i86.

' tumble-bugs." The
beetles are usually
blackish or bronze
brown in color, but
sometimes bril-
liantly metallic blue,
green, coppery, or
bronzed, and often
we find in the male
a prominent, curved
horn on the top of
the head, and angu-
lar processes on the
thorax.

Other large or
moderate-sized spe-
cies make holes
close to or under
droppings in fields,
working mostly at

A "tumble-bug," Copris Carolina.— a, larva; b, the nio'ht and Icavingf
cell in which it lived; c, pupa; d, female beetle; e to i,
structural details.

evidences of their

Fig. 187.

presence in the
shape of little piles of fresh dirt next to or even on top of the
droppings ; cow-dung being the favorite food. These beetles

usually have deeply striated wing-
covers, are more stockily built
than those previously mentioned,
and belong mo.stly to the genus
Geofrypes.

A series of small, more slender
or oblong, black or reddish beetles
is often found in considerable num-
bers burrowing in or under excre-
ment, and these have similar habits
and are referable to the genera
ApJiodius or Atceniiis.

Very often large, clumsy "white
grubs" are found in manure heaps, and these are larvae of

Apliodius granarius, much enlarged.

THE IXSECT WORLD.

199

beetles helonyinq- to this scries. None of them are in any way
injurious.

The e.xeeption in food habits in this family i.s found in the
genus Trox, containing oblong, very convex species, with rough,
tuberculate or pitted wing-covers, and a deeply furrowed thorax.
They are usually more or less incrusted with dirt, are found
feeding under old skins, bones, or hoofs, and are, as scavengers,
at least innoxious.

The more typical ' ' leaf-chafers' ' are of diverse forms, often
common and economically important. Among the first we reach

Fig. 188.

Rose-chafer, Macrodaclyliis suhspinosus. — a, beetle ; b, head and thorax, in outline, from
side ; ^ to ^, structural details.

the genus Macrodactylus, of which the "rose-chafer," or
"rose-bug" is a member. This appears in June at about the
time roses and grapes come into blossom, and eats their flowers
in preference to anything else.

Occasionally, for a series of years, the insects appear in ever-
increasing abundance, until the swarms are so great that they
ruin not only vineyards but orchards and gardens, eating almost
every kind of fruit and flower. In the presence of such swarms
we are almost helpless, and insecticides are of no possible use.
No contact poison kills them, and the arsenites or other stomach

AA^ ECONOMIC ENTOMOLOGY.

poisons act too slowly, as two or three days suffice to ruin a vine-
yard. Lest this seem strange, I will state that I have seen on
hundreds of acres of vineyard every vine bearing multitudes, and
every bunch of blossoms from two to ten, or even more beetles.
I have counted over twenty on a single apple, and a full-blown
rose may bear as many as thirty or even more. We are reduced

Fig

Larva, a, and pupa.y", of rose-chafer ; b Xo e, ,i; , It, structural details.

to actually collecting the specimens from the vines by means of
funnel or umbrella- shaped collectors, adapted to the method of
cultivation in use. They drop readily when the vines are jarred,
and the collector should be so made as to roll them to the centre
and into an attached pail containing kerosene. This must be
done not only daily, but continuously for several days until the
flight is over or the grapes have set, for well-set grapes are
rarely eaten. Fortunately, a period of abnormal increase seems
to be followed by a period of decrease, though the lengths of the
periods have not been ascertained. The larvae feed in light land
on the roots of various plants, but principally on grass. They
pupate in spring, shortly before changing to the ?dult condition,
and by ploughing infested sod at this time a large proportion can
be destroyed. When only moderate numbers occur, lime often
serves to protect the plants, or, better, the Bordeaux mixture,
which is distasteful to them.

The "May-beetles," or "June-bugs," sometimes termed
" cockchafers," are much larger, and mostly members of the genus

THE INSECT' irOR/.D.

Lachnostcrna. Tliey fly at night, are readily attracted to light,
and often come into rooms, clumsily and noisily bumping against
all sorts of obstructions until they c\enlually strike something
which sends them heavily to the floor. We ha\e many species
more or less resembling each other, and all chestnut brown or
yellowish in color. Some years they are very abundant and
cause injury by eating the foliage of trees or shrubs. I have
found them eating pieces out of the stalks of recently set apples

Fig. 190.

May-beetle. — i, pupa in earthen cell ; 2, larva or white grub ; 3, 4, beetle,
from side and above.

and pears, causing the fruit to wilt and drop. The larvae live
on grass and other roots, and are typical " white-grubs." Culti-
vated crops are frequently attacked and much injury is some-
times caused. The larval period has not yet been satisfactorily
determined for all species, and varies, as does also the time for
changing to the adult condition. Frequent rotation and fall
ploughing are to be recommended, and where grass lands are
infested, heavy top-dressings of kainit and nitrate of soda have
proved beneficial. Wherever ploughing is done in infested fields,
chickens should be encouraged to follow in the furrow to pick
up the grubs.

Where young trees are to be protected from the beetles, jarring
them into an umbrella two or thrte times early in the evening

202 AN ECONOMIC ENTOMOLOGY.

will prove effective, as they do not fly much after nine o'clock,
except on unusually warm and sultry nights.

Frequentl)- we iind on grape and Virginia-creeper, during
midsummer, a small chafer witii clay-yellow, rather shining, and
striated wing-covers, feeding upon the leaves. This is the
Anomala lucicola, which varies also to a shining black. It is
occasionally nimierous enough to cause notable injury, but

P'iG. 191.

Fig. 192.

Anomala lucicola.— a, b, lar\'a ; c, pupa in
larval skin ; d, r,/, adult beetles.

Goldsmith beetle,
Cotalpa huiigi'ra.

yields readily to any of the arsenites. The larvae live in light
soil, feed upon the roots of grasses, and pupate in late fall, the
adult forming soon after and remaining within the cast larval
skin until ready to emerge in early summer.

Also found during the day on grape foliage, or flying toward
it during early evening, is a large, shining, tan-yellow chafer,
with eight black spots, two on the thorax and six on the wing-
covers. This is the Pelidnota punctata, or ' ' spotted vine-chafer, ' '
which feeds upon the leaves, but rarely does noticeable injury.
The larvae feed upon decaying roots and stumps, and I have
taken both lar\a and pupa out of a rotten cedar trunk.

Swamp-willow in the East is the food of Cotalpa lanigera, a
beetle very similar in size and shape to the preceding, but of a
beautiful shining, lemon yellow, the head glittering with a golden
sheen, hence known as the "goldsmith beetle." Beneath it is
of a burnished copper color, densely clothed with white woolly
hair. It is not injurious, and mentioned here only because of its
beauty. Some of its allies in the Southwest and in the tropics
are of the most brilliant golden and silvery tints,

THE INSECT WORLD.

203

A beetle that sometimes does considerable injury to sugar-cane
and corn in the Southern States is the " sugar-cane beetle," Li-
•rynis rugiccps. Unfortu-
nately, we do not yet know-
its entire life history, aiul, as
the 'injuries seem to have
been rather local and occa-
sional, it may b^ that it will
not prove of wide or gen-
eral importance. No satis-
factory method of dealing
with it is known at present.

In the genera Xyloyctcs,
Strategus, Dynastcs, and
Philcuriis, we have a series
of species more or less
bizarre in form, with curious
horns and processes on
head or thorax or both, but
not of economic interest,
since neither beetles nor
larvae are found on culti-
vated plants. Ash furnishes
food for several of the spe-
cies in both larval and adult
form.

Beginning with the genus
Allorhina^ we have a series
of beetles that frequent
flowers, feeding on pollen,
but largely repaying what
they devour by the benefit
they confer in poUenizing.
Sometimes, however, they prefer ripening fruits or even corn
when in milk, and then become troublesome. Belonging to this
genus Allorhina are velvety-green and dull-brown beetles, an
inch or more in length, which fly during the day with a buzzing
sound somewhat like a bumble-bee, and usually close to the sur-
face of the ground, except where they attack fruit. Yet I have

W.V\.U\GUO\-S.

Ligvvus rugict'ps. — The beetle and its work.

204

AN ECONOMIC ENTOMOLOGY.

seen hundreds of them flying about among half a dozen pkim-
trees, apparently injuring nothing but possibly themselves.
Their larvae, however, feed on grass roots and are often trouble-
some on lawns. They are quite large creatures and very hairy,
with a fashion of travelling on the back instead of the legs, when
removed from their congenial soil. Heavy top-dressings of
kainit and tobacco have proved about as effective as anything in
dealing with these insects, though on a small scale the kerosene
emulsion diluted ten times, and then washed into the soil by rain
or frequent waterings, has proved effective. On any large area

Fig. 194.

Alio) hina nitida.—a, larva ; b, pupa ; c, adult ; d io g, structural details of larva.

this process would probably be too expensive. The species is
more common southward, and is more likely to become trouble-
some on lawns, in parks, and in gardens than in the field.

To this same group belongs the "Indian Ceionia.,'' Euphoria
inda, which is one of the earliest of our Eastern beetles, flying
in April or May over sandy or bare spots, close to the ground.
At this time it is sometimes found on flowers, but remains only
a few days. In early September a new brood appears, and this
is occasionally troublesome, the beetles eating into ripe fruits or
into corn. They have never yet appeared in such numbers,
however, as to make remedial measures necessary.

Taken as a whole, the Lamellicorns contain no directly bene-
ficial insects, and the white-grub larvae are in many cases injurious
when they feed on the roots of cultivated plants. Where a
variety of cultivated crops follow each other, there is little chance
for their excessive development, and frequent rotation is there-
fore indicated, with as short a period in grass as may be. As

THE INSECT WORLD. 205

the beetles in most cases appear in spring and oviposit late in
May or in June, land bare at that time will probably escape.
Fall sowing of crimson clover, to be turned under by the middle
ol" May or before, will in some cases protect the land and act as a
green manure if required ; or it may be allowed to remain until
mature to make hay, and, if then ploughed and put into potatoes
or some crop which tlie white-grubs do not attack, such as are
then in the ground will be starved out. Where white-grubs are
abundant, strawberries should not follow sod or other grass crop
directly, and the beds should be kept clean, at least through the
second year. Where the culprits are species of Lac/mosterna,
fall ploughing is indicated, since this will turn out the newly-formed
beetles at an unseasonable period, and will cause their death in
most cases.

We now reach the great series of P/iytophaga, in which the
tarsi are apparently four-jointed, the third joint deeply lobed.
Two families belong here, — the Cerambycidcs, or long-horned
beetles, and the Chrysomclidce, or leaf-beetles. The ' ' long-
horned " beetles are so named from their usually well-developed,
slender antennae, rarely shorter than the body, and often several
times as long. They are usually more or less cylindrical, often
with a vertical head, and always with well-developed mandibles.

The larvae are wood-borers, using that term in a somewhat
loose sense to include roots and the more solid parts of a few
herbaceous plants, and are always cylindrical, the segments well
marked, those immediately behind the head considerably enlarged,
while anally they often taper quite abruptly. They are known as
' ' round-headed ' ' borers to distinguish them from the ' ' flat-
headed " larvae of the Buprcstidcr, and the jaws, though rather
small, are powerfully developed, fitted for cutting the hardest
wood-fibre. In food habits the insects vary greatly, some attack-
ing only dead or dying tissue, while others infest sound trees
only. Perhaps in most cases they do best in somewhat weakened
trees which their ravages soon kill entirely.

Among our largest species are the Prionids in which the
margin of the thorax is thin, sharp, and often toothed, and our
most common species, extending over a large part of the United
States, is Orthosoma bninneum, an oblong, somewhat flattened,
brown species, from one and one-half to two inches or more in

2o6

AN ECONOMIC ENTOMOLOGY.

length. It is not economically important, unlike the "broad-
necked Prionus," P. laticollis, whose larvae in blackberry are
known as "giant root-borers." The beetle is black, robust,
broader than usual, with a broad, toothed thorax, and from one
to two inches in length. The larvae are immense, nearly three
inches for a full-grown female, and they feed in the roots of a

Fig. 195.

The " giant root-borer," Prionus /a/t'coNis.— 'La.rva, pupa, and adult.

variety of trees and plants, including chestnut, oak, cherry, apple,
grape, and blackberry. They require three years to reach
maturity, and are sometimes decidedly troublesome. There is no
way of reaching the larvae except to dig them out, and in black-
berry fields the sudden wilting of part or all of a hill indicates
almost infallibly the presence ol one or more, which should then
be found and destroyed at once. Grape and apple stand the
injury better, but when a tree becomes badly infested nothing
remains but to take it out and burn it. Even large trees are

THE IXSECT WORLD.

207

Fig. 196.

Phymatodrs aiiitriins : pupa and adult.

sometimes killed, an o\d cherry-tree, fully eighteen inches in
trunk diameter, which died rather suddenly, having the roots
absolutely riddled in every direction by a dozen or more of these
immense creatures.

The species of Phymatodes are much smaller, a little flattened,
with an oval thorax and a tendency to blue and yellow colors.
The larvae feed only in dead or
dying wood : P. anicenus, a bright
blue species with yellow thorax,
attacking dead shoots of grape,
while P. varius and P. variabilis
live under the bark of oak cord-
wood. The beetles appear in
spring and lay their eggs in
dying wood or in wood cut
during the winter, often in such
numbers that the bark is com-
pletely loosened by the larvae and will, next spring, slip off in
its entirety. They are hence called "bark-slippers" by wood-
men. In the Southern States they infest tan-bark, sometimes
injuring it considerably. Cutting the trees during the summer,
after the beetles have disappeared, or very early in fall will put
the bark and wood in such condition that it will not be attractive
the season next following.

The species oi Elaphidion are narrow, brown beetles, covered
with whitish, somewhat mot-
tled pubescence, and ha\'e long r\G. 197.
and rather stout antennae.
They are known as " oak-
pruners," because the larvae
of several species bore into
twigs and branches of oak and,
when nearly full grown, girdle
them from the inside, so that
the first high wind of early
winter breaks them off, carry
ing the larvae to the ground.
Transformation is completed in the June or July following. Often,
during late summer, the wilting of a twig or small branch indi-

The oak-piuiier, Elaphidiuii f<ai allclum.
— a, larva ; b, pupa in its burrow ; c, beetle ;
kk, cut ends of the twig ; d to /, structural
details.

AN ECONOMIC ENTOMOLOGY.

Fig. 198.

cates the presence of such a larva. Apple-trees are sometimes
attacked, and the best measure for general adoption is the sys-
tematic gathering and burning of all fallen twigs and branches
during the winter. The insects are not confined to terminal
branches only, but sometimes attack the trunks of young shoots
or trees after a fire has been over the ground and scorched them,
and in such cases the larvae make no effort to girdle.

In the genus Cyllene we have moderate-sized species that
are dark velvety brown or blackish, with bright golden-yellow
bands. Of these, C. pidus infests hickory not uncommonly,
and appears in spring, while C. robinice infests the locust, and
appears in fall. This latter is a serious pest, and makes growing
locusts simply impossible in many localities. As soon as a tree
attains a moderate size it is riddled with the
large holes made by the larvae, and leads but
a sickly life for a few years thereafter, event-
ually dying down to the ground. The
beetles themselves frequent the flowers of
golden-rod, and may be collected there in
great numbers, the females resorting to the
locusts only when ready to oviposit. An
allied, yet larger and prettier, species, Pla-
gionotus speciosus, bores into maple, but
is usually somewhat rare and has not proved
injurious until very recently in some parts of New Hampshire,
where certain shade-trees suffered.

We sometimes find a small larva belonging to this series boring
into the branches and smaller shoots of currant-
bushes, and early in spring these change to a
small, brown, somewhat flattened beetle, rarely
exceeding one-quarter of an inch in length,
clothed with white hair grouped to form two
white spots towards the end of the wing-covers.
This is the Psenocorjis supernotatus, which is
occasionally abundant enough to be troublesome.
It can be held in check by close pruning during
the winter, the cuttings to be burnt before spring
opens to destroy the contained larvae.

In late spring or early summer some of the terminal shoots

Plagionotus speciosus.

F"lG. 199.

American cur-
rant-borer, Pseno-
corus supernotatus ,
enlarged.

THE IiYSF.CT IVOKI.D.

209

of applc-trces may suddenly wilt and the leaves become brown
and dry, the fruit, if any, dropping to the ground. These
wilted shoots will be found hollowed out, and the culprit is the
larva of another little brown longicorn, about one-quarter of an
inch in length, (juite robust and cylindrical, the wing-covers a
little mottled with rather long, pale hair. It is a species of
Eupogonius which has not figured much in economic literature,
because its injuries rarely amount to more than a light summer
pruning. On smaller trees the infested shoots can be cut and
destroyed and on larger trees careful winter pruning is indicated.
A well-known orchard pest is the round-headed apple-borer,
the larva of the Sapcrda Candida. It attacks quince in prefer-

FiG. 200.

U ^

C h

Round-head apple-borer, Saperda Candida. — a, larva ; b, pupa; c, adult.

ence even to apple, but is more rarely found in pear. The
beetle appears late in June or early in July, depending somewhat
upon latitude, and lays its eggs on the trunk, as near to the surface
of the ground as possible, under a loose bark-scale or in a little
hole gnawed by its mandibles. The larva lives for a year in the sap
wood, then bores into the trunk, up or down, sometimes some
distance below the surface, and in the spring of the third year
changes to a beetle. Trees of quite large size are killed in a
very few years, and for some time before are sickly and do not
properly mature a crop of fruit. All sorts of remedies and
devices have been proposed, cutting out the larvae being the one
most relied upon even yet. This means, in many cases, making
an additional large wound in the tree, and sometimes the remedy
is worse than the disease. The best method of protection, and

14

AN ECONOMIC ENTOMOLOGY.

Fig

this applies as well to other species infesting tree-trunks, — e.g.,
the locust-borer, — is mechanical, the trunk being covered or
coated by some material impenetrable, repellent, or destructive
of or to the adults, thus preventing oviposition. The most
satisfactory and lasting measure, all things considered, is cover-
ing the lower portion of the trunk with wire mosquito-netting,
tying at the top and hilling up against it at the bottom. The
netting should extend at least two feet up the trunk and above
that a coat of whitewash should be maintained during the danger
season. Other measures, equally useful here, have been already
referred to when speaking of the " flat-headed borers."

In the genus Oncideres we find a curious and interesting egg-
laying habit : the beetle lays an ^^^ in a twig or branch, and
then girdles it at a little distance below, eating
so far through that a high wind brings it down.
The twig wilts at once and the wood is then in
the exact condition desired by the larva, which
\ '^^L ^ undergoes its transformations undisturbed by
growth or undesired moisture. Sometimes
shade-trees are attacked ; but merely gathering
and burning the fallen wood keeps the insects
in check.

There are many other longicorns in our fauna,
nearly six hundred species being listed in the
catalogues, and many are beautiful as well as
interesting. The few species referred to here
do not even illustrate all the different types,
but are all that are sufficiently injurious to be
referred to at any length. Wooded regions
furnish the greatest variety of species, and all
portions of the trees furnish support for their
larvae.

The family Chrysomelidcs, or leaf-beetles, contains species
that, in the main, feed upon leaf-tissue in the larval as well as
adult stages, and many of them attack cultivated crops. The
beetles may be distinguished by the tarsal structure already
described, by their usually moderate or small size, short antennae
which are not situated on frontal prominences, and by their
usually margined, not cylindrical prothorax. The larvae vary

The "twig-gird-
ler," Oncideres cin-
gulatus. — a, beetle
at work ; b, egg-
puncture ; c, gird-
ling done by beetle ;
c, egg.

l-'lC. 2()I.

Wciik 111 llic Kiiiiul-lK'.ul applc-borci , Sapt'xfa nunlnla. a. iiiiiicHiic in wliich t);.i;
is laid ; />. same in sci lion : r, luilc from wliich l>citlc lias finer>;e(l ; /, same in section ;
.(Tt pujia ill its cell.

1-"|C.. 2CJ2.

Work of the locust-borer, Cyllenc robitiiu:.

rilK INSECT WORLD.

Fig. 204.

considerably in form and habit, but are often more or less viscid,
and are then termed slugs.

Belonging to the genus Lema is a little series of species, several
of which feed upon the potato, and of these the best known is
the Lema j-Iincata, or " 3 lined potato-beetle." It is yellow in
color, the head and thorax much narrower than the body, and
the wing-covers have three broad, black stripes. It is rarely
abundant now-a-days, though at one time a somewhat important
species, and it may be easily controlled by the use of the arsenites.
In fact it is the treatment adopted for the better-known "Colo-
rado " beetle that has in a large measure exterminated the Lema.

Somewhat allied in form are two species of Crioceris, both
feeding on asparagus, and both introductions from Europe. The
common "asparagus-beetle," C. asparagi, is about one-fourth
of an inch in length, the wing-covers black with red or yellow
markings, the thorax red with black dots. It hibernates as an
adult, and appears early in spring, eating into the asparagus
shoots and laying its eggs upon them.
These eggs are black and quite long, cylin-
drical, set on end so as to project from the
shoots in every direction. The larvae hatch
soon thereafter, and are slimy, greenish
slugs, with black dottings, a blackish head,
and black legs. They often do great in-
jury, particularly on young plants. On
beds where cutting is done, a few shoots
should be allowed to grow as traps during
the cutting season, and on these the ma-
jority of beetles will oviposit. In a week
they should be cut and destroyed, other
shoots being allowed to take their place, to
be similarly treated thereafter. If this prac-
tice is kept up for a month, no injury need
be anticipated later on, as the species will
be too much reduced in numbers to be-
come troublesome. No volunteer aspara-
gus should be permitted, as otherwise the insects will multiply
there. In young beds the beetles cannot be checked, because
spraying the feathery leaves is impracticable, but after the larvae

Asparagus-beetle, Crio-
ceris asparagi: larva,
adult, and shoot with eggs.

212 AN ECONOMIC ENTOMOLOGY.

develop, they may be readily brushed off with a stick in the
middle of a hot day and few of them ever get back, a short
period on the hot soil proving fatal. The work can be done
very rapidly, and is needed two or three times only to secure
entire protection. Where a field of old shoots becomes badly
infested by larvae, much benefit may be derived by a thorough
dusting with fresh, dry slacked lime early in the morning while
the plants are yet a little moist with dew. The lime, if properly
prepared, is sufficiently caustic to burn holes into and kill the
slimy larvce. As new specimens are constantly hatching, this
dusting must be done several times at short intervals, but is sure
to prove effective if thoroughly carried out.

The " 1 2-spotted asparagus beetle," C. 12-punctatus, is some-
what larger and more robust, uniformly reddish in color, with
twelve black spots on the wing-covers. It is as yet less common
than its ally and not so widely distributed, but may be treated in
much the same way.

The species of Fidia are robust, rather long-legged creatures,
covered with short hair, giving them a more or less marked gray
appearance, and they feed largely upon grape. Fidia viticida
has proved locally injurious in Ohio, and, as the species occurs
over a large portion of our country, it may break out anywhere
at almost any time. The beetle feeds upon the foliage, eating
irregular holes on the upper surface in June. Eggs are laid on
the trunk of the vine or on the branches in any available crevice,
and the larvae drop to the ground when hatched, making their
way beneath it as best they may, to the rootlets upon which they
feed. Remedial measures have not as yet proved very satisfac-
tory, but spraying with a strong arsenical mixture, using lime to
avoid burning the foliage, will kill many of the beetles. Culti-
vating the ground so as to have a loose powdery top soil without
crevices leading to the roots, which should also be covered as
deeply as possible, will prevent many of the larvae from reaching
their feeding place.

Strawberry plants are sometimes injured by whitish larvae
feeding upon the roots, and from these are produced small, shin-
ing, black or brownish beetles belonging to Paria aterrima, or
certain allied species popularly known as ' ' strawberry root-
borers." The best measures here are clean culture and frequent

THE INSECT WORLD.

213

chancre of location for the strawberry beds. The insects are
rarely troublesome in the Eastern, but often injurious in the
Central States. Old beds should be ploughed out and destroyed
as soon as they have been picked, and when new beds are set out
care should be used in selecting plants free from insect attack.
Where a two-year picking rotation is used and the old plants are
immediately destroyed, the species are not able to increase ex-
cessively. The arsenites may be satisfactorily used to kill thi

Fig. 205.

Grape-root-worm, Fidia viticida.—A, adult; B, pupa; C, larva; the other letters refer
to details of larval structure.

adults when they are noticed feeding upon the foliage. Using
commercial fertilizers instead of barn-yard manure is also to be
recommended.

Perhaps the best-known species of this family is the " potato-
bug," or "potato-beetle," or " lo-lined beetle," or "Colorado
potato-beetle," Doryphora lo-lineata. No description of this
insect is necessary, the figures serving to illustrate all its stages
sufficiently well. The insects winter underground as adults or
pupae, and the beetles emerge early in spring, attacking the
young plants as soon as they show above ground, and laying
eggs for the livid-reddish larv^. About midsummer these have
matured a second brood of beetles, and a second brood of larvae

214

AN ECONOMIC ENTOMOLOGY.

follows shortly thereafter, resulting in a fall supply of beetles,
which, as a rule, hibernate. Sometimes a third partial brood of
larvae reaches the pupal state, and hibernates in that condition.
The arsenites are well-known and approved remedies, used at the
rate of one pound in from seventy-five to one hundred gallons
of water, and several machines especially intended for spraying
potato-fields are on the market. The insect maintains itself
unchecked, because, while active war is waged against the first

Fig. 206.

The Colorado potato-beetle, Doryphora lo-lineaia.—a, a, egg patches ; b, b, b, larva in
difterent stages of growth ; c, pupa; d, beetle; e, its elytra enlarged.

brood, little attention is paid to the second, and this is usually
allowed to mature and provide for a new crop the year following.
Spraying should be done first as soon as the beetles begin feed-
ing, to prevent oviposition if possible ; it should be done a sec-
ond time when larvae appear generally, and it should be done as
often thereafter as beetles or larva are noticed infesting the
plants.

The species of Diabrotica are rather slender, with long an-
tennae ; of a green or yellow color, with black spots or stripes.
The adults feed on leaves, flowers, or pollen, but the larvae, which
are white and slender, usually feed in the roots or stems of plants.
One of our most common forms, D. vittata, is known as " the
striped cucumber-beetle," and is yellow with black stripes on the

THE IXSECT WORLD. 215

wing-covers. It feeds on all kinds of cucurbit vines, and on
many other plants as well, doing injury by eating into the stem
of the young shoots at or below the surface, where it has a ten-
dency to hide during the middle of the day. The larvae live in
the main roots underground, making short galleries, which, if
numerous, weaken or even kill the plant. The beedes winter as
adults. A free use of tobacco dust around young vines or other
injured plants is usually protective, though in some localities the
farmers resort to " driving." They do this before the middle of
the day, sowing air-slacked lime with the wind, and this seems
to be sufficiendy offensive to the insects to induce them to leave
for fields to the leeward, where they, of course, become doubly
injurious unless also driven off. Planting an excess of seed to
distribute the injury is a common practice, and so is starting the
plants in baskets and setting them out when well established and
able to resist injury. Melon and other cucurbit vines should
always be plowed out, raked up, and destroyed as soon as pos-
sible after the crop is off, to destroy any larvae that may be then
in the roots.

An allied and equally common species, feeding as an adult
upon a great variety of plants, is the D. i2-piinctata, or "12-
spotted Diabrotica. ' ' This is somewhat larger than the preced-
ing, with a more oval body, and has twelve black spots on the
greenish-yellow wing-covers. The larva feeds on the roots of a
variety of plants and becomes injurious to corn in the Southern
States. There are two broods, and the beetles winter in the
adult stage. No direct remedy is known, but good cultivation
and a liberal application of stimulating fertilizers is advisable to
enable the corn-plant to resist and outgrow attack. Clean cul-
ture is the greatest essential, and this of itself will do much to
reduce injury.

The ' ' corn-root Diabrotica' ' of the Western and Central
States is of a uniform, pale-green color, named D. longicornis,
from its long antennae, and its larva has proved a serious pest to
corn. The complete life history of the insect is known, and as it
winters in the o.^^ state in corn-fields, simple rotation is all that
is necessary to destroy the species. It can never become injuri-
ous unless corn follows corn year after year, and even a single
year rvithout corn serves to completely rid a field of the pest.

KiG. 209.

Fig. 210.

Fig. 207, Lenia Irilineata. Fig. 208, a, a, larva; ; c , pupa ; d, eggs of Lema IriUneata.
Fig. 209, Diabroiica 12-punctata: a, egg; b, larva; c, injury in corn-stalk; d, pupa;
e, beetle. Fig. 210, Diabrotica longicornis : a, adult ; b, pupa ; c, larva ; d, same in its
case. ¥\g. -211, Diabroiica vitlata. Fig. 212, larva of same. Fig. 213, its pupa.
216

THE INSECT WORLD. 217

The genus Galcrnca contains a series of rather small, oblong
species, mostly dirty clay-yellow in color, and more or less black
marked or spotted. Of these none is more troublesome than the
" elm-leaf beetle," Galcnica xautlioweUcna, which is another of
our undesirable imp(,)rtations from Europe. It is rather greenish
yellow when fresh, with two black stripes on the wing-covers.
It hibernates as a beetle wherever it can find shelter, and attacks
the leaves of elms in spring as soon as they are well grown,
eating irregular round holes, so they soon look as if loads of
shot had been fired through them in every direction. The yel-
low, bottle-shaped eggs are laid in double rows on the under
sides of the leaves, and from them hatch the yellow, black-spotted
larvae, covered with little bristly tufts of hair. In the northern
part of its range, including the red shale of New Jersey, a single
brood is normal, but south of this, and including an extension
into Long Island, the insect has two broods annually, and at
Washington or further south may have three or even more. As
against these insects the arsenites are effective, and the trees
should be sprayed, preferably with the arsenate of lead, just as
soon as the beetles begin feeding. The object is to destroy as
many of the hibernating forms as possible, and to prevent egg-
laying in large part. A second spraying should be given when
the eggs begin hatching, to destroy the young larvae, and in
serious cases a third spraying a week or ten days thereafter will
be beneficial. When the larvae are full grown they descend the
trunk to the ground, where they change to bright-yellow pupae
among the grass or rubbish on the surface. Here they may be
destroyed by hot water, kerosene, strong soap-suds, lime, or
other suitable substances, and the second brood, where such
occurs, may thus be materially lessened. Where there are two
broods or more, repeated .sprayings will be necessary, extending
throughout the summer. If these methods are generally adopted
the insect can be satisfactorily controlled. Protecting a few trees
only among many that are neglected will always be difficult and
can be at best only partly successful.*

* For detailed information concerning the treatment of trees in cities
or towns, or on a large scale, the publications of tlie United States De-
partment of Agriculture and of the New Jersey Experiment Station
should be consulted.

2l8

A2V ECONOMIC ENTOMOLOGY.

S«,

THE INSECT IVOKLD. 219

Distinct from all the forms hitherto mentioned are the "flea-
beetles," so called because of their greatly enlarged hind femora,
giving them the power of making sudden leaps ending in flight.
We have many sjiccies, and some of them are decidedly injurious
and troublesome to deal with.

The grape flea-beetle is a well-known species called Haltica
chalybca, from its steel-blue color, and it feeds both as adult and
larva on the leaves of the grape. The larvae are blackish and
slender, slug-like and somewhat viscid, feeding in company
during a great part of their growth. They are easily controlled
by any stomach poison, and the Bordeaux mixture, applied as a
fungicide, seems to be effective in keeping them in check.

The genera Crepidodera and Epitrix contain a number of
small species, among which the "cucumber flea-beetle," or
' ' potato-flea, ' ' Epitrix accumeris, easily ranks first. As a small
black beetle, it eats little round holes into the leaves of potato,
tomato, egg-plant, and a variety of other solanaceous plants, as
well as into those of melon, cucumber, and other cucurbitaceous
vines. Potatoes seem rather the favorite food, and where the
beetles and their little holes are numerous the leaves turn brown
and die, checking the growth of the plant, and hence of the
crop. The larvae are leaf- and stem-miners, but do little or no
damage. Usually Paris-green and London-purple are satisfac-
tory remedies, and it has been observed that the Bordeaux mix-
ture acts as a deterrent when liberally used, serving thus the
double purpose of checking insect injury and plant disease.
Tobacco is also a very satisfactory material used as a decoc-
tion, but is scarcely economical except on a small scale or in
gardens.

The "sweet-potato flea," Ch(£tocnema conjinis, is an inter-
esting, if troublesome, small, bronzed beetle, attacking the leaves
of the young plants just after they have been set out, and eating
little channels along the veins, finally making the net-work so
complete that the leaves shrivel and dry. If the vines get a fair
start, they outgrow the injury very rapidly, but cold, wet weather,
by retarding growth, sometimes enables the insects to kill them.
Dipping the plants before they are set out in the arsenate of lead
mixture, at the rate of fifteen ounces to fifty gallons of water, will
prove a satisfactory protection without danger of injury to the

Fig. 217.

Fig. 219.

Fig. 217, grape flea-beetle, Haltica chalybea, in all its stages, on a grape slioot. Fig.
218, work of the sweet-potato flea on the leaves. Fig. 219, pale-striped flea-beetle, Sys-
tena blanda. Fig. 220, the rosy Hispa, Odontota rosea.
220

THE INSECT WORLD.

plants. Or they may l^e thoroughly sprayed with the Bordeaux
mixture immediately after being- set out.

Of somewhat larger size and more slender, graceful form are
the species oi Sysloia, and of these, 6". blanda, the " pale-striped
llea-beetle," has become best known by reason of its injury on a
great variety of plants, including sugar-beets. As with the other
"fleas" it is injurious in the beetle stage only, and, as a rule, in
early summer on young plants. I have seen it ruin an entire
field of carrots, and have found it on melons, potatoes, beets, and
pig-weed in equal abundance. Its life history has not been pub-
lished, but its larva is said to feed upon corn-roots. This is cer-
tainly not universally true, and its native food-plant in the early
stages remains to be ascertained. As with otiier leaf-feeding
forms, we are referred to the arsenites, or, as a means of protection
only, to air-slacked lime, which will drive the beetles to wild
plants, leaving the lime-dusted crop free.

In the genus Phyllotreta we find another series of small species
not exceeding one-eighth of an inch in length, ordinarily black in
color, with yellow stripes or

spots on the wing-covers. The Fig. 221.

most common species in the
East is the ' ' wavy-striped flea-
beetle," P. vittata, in which
there is a distinct yellow stripe
through the middle of each ely-
tron. The adults feed upon the
leaves of cabbage, radish, mus-
tard, and others of the cruciferae,
while the larvae live as miners
in the tissues of the same plants.
In dealing with this species
the important points are clean
culture and keeping down all
cruciferous weeds. If in addi-
tion all crop remnants are promptly gathered and destroyed, no
serious danger need be apprehended.

Following the flea-beetles is a series of very curious, somewhat
wedge-shaped insects, the Hispida, in which the antennae are
thickenedf and the elytra, or wing-covers, broaden to the tip,

Striped flea-beetle, Phyllotieia
a, larva ; b, adult.

AlV ECONOMIC ENTOMOLOGY.

where they are rather abruptly terminated. The larvae are leaf-
miners, and perhaps the most common species is the Odo7itota
dorsalis, or locust-beetle, which occurs abundantly on the leaves
in early summer, and is orange in color, with a broad black
stripe on the centre of each elytron. The eggs are covered with
a little mass of excrement, and are laid singly, few leaves con-
taining more than two or three. Not much real injury is done
by any of the species, and the suggestion that the adults feed
exposed and succumb readily to the arsenites is all that is neces-
sary on the subject of remedies.

The adult Cassidce are called "tortoise-beetles," or, by the
sweet-potato grower, "golden bugs." They are characterized
by their broad, almost quadrate form, flat under and convex
upper side, and by the more or less metallic-yellow or golden
color of the elytra and upper surface generally. Most of the
species feed upon Convolvulus^ to which natural family the sweet-
potato belongs, and the
^^^- ^^^' latter is about the only cul-

tivated crop suffering from
the attacks of insects of this
series. The beetles hiber-
nate and appear in the sweet-
potato fields as soon as the
crop is set out, eating irreg-
ular holes in the leaves, and
laying their eggs, encased in
a mass of excrement, on the
under surface. The larvae
are known as "peddlers,"
because they have piled
upon a pair of anal forks all
the cast skins and a part of
their excrement, forming a
sort of shelter, umbrella, or
"pack," to which latter
resemblance they owe the
common name. The most abundant form is the Cassida bivittata,
or "two-striped tortoise-beetle," so named from the two black
stripes on each wing-cover. Following closely is the Coptocycla

Coptocycla auiiclialcea. — a, larvae, or ped-
dlers, with their packs; b, larva with pack
removed ; c, pupa.

T]IE IXSECT WORLD.

223

mirichalcca, so named because of its resemblance to a drop of
molten gold. The injury is done by these species just after the
plants are set out and before they get a start. Where the season
is unfavorable to rapid growth, some plants may be killed, but
under ordinary conditions they are soon out of danger. Good
practice is to set only large, well-developed plants, or to dip
everything before setting out in the arsenate of lead mixture
recommended against the flea-beetles. Finally, it has been found
that chickens are fond of the insects in all stages, and by turning
loose a sufficient number in the fields after the plants have been
set out practical exemption is secured.

The bean- and pea- weevils constitute a little family by them-
selves under the term Bnichida. They agree with the leaf-
beetles in general structure, but
have a small head, prolonged into ^'"^'' ^"-^^'

a blunt snout, a very obese abdo-
men, exposed at the tip by the
short, square wing-covers, and
much enlarged hind legs, which
are not used for leaping. They
are always small and usually more
or less ashen-gray in color, covered

vi_ i."i" u 1- • 1 u* u Bean-weevil, Biiiclius fabcr, much

With whitish hair or scales, which , ,' ■ <• , ^ u

'_ enlarged ; b, an infested bean.

form variably evident markings on

the wing-covers. The beetles are often found in dried seeds of
leguminous plants, — peas, beans, lentils, or the like, — and are
sometimes seriously injurious in the stored product, lessening
also or destroying the germinating power. The beetles come
out normally in the spring, and after pairing the females lay
their eggs in the young pods of the plants affected by them.
The larvae work their way into the forming seed and grow very
slowly, the species varying somewhat in the details of their life
history. Our only method of controlling the insects is in the
stored product, or seed, and here by means of bisulphide of car-
bon we can kill larvae as well as adult beetles, in any moderately
tight receptacle. The rule should be, gather the entire crop and
allow nothing to remain in the field ; plant only sound seed, and
never under any circumstances throw away "weevilly" peas,
beans, lentils, etc. They should always be burnt, or otherwise

V

224

A,V ECONOMIC ENTOMOLOGY.

completely destroyed. Wild as well as cultivated plants are
infested, though we do not know that insects infesting our garden
varieties are carried over by other wild species.

Fig. 224.

Fig. 225.

'Pe^2L-\^zfi\\\, Bruchus pisi—c, larva; rf, pupa; (^, adult ; all enlarged.

We now reach the series Hderomera, or beetles in which the
fore and middle tarsi have five joints, while the posterior are
four-jointed only. We have rather a large number of families,
many with a few species only, and as a whole they are feeders
in or on decaying or dry vegetable tissue, whether herbaceous,
woody, or fungoid in character. There are exceptions, of course,
but that is the rule.

The Tencbrionidce, or "darkling-beetles." contain species
ranging from quite small to very large, found under all sorts of
conditions, but most frequently beneath
bark of trees, on fungi, or under stones,
among dry vegetable matter. There is
no uniformity in appearance, but in most
instances the antennae are more or less
moniliform, or bead-like. The majority
of our species are Western, occurring in
their greatest variety in the Rocky
Mountain region, but none, so far as I
know, trouble green vegetation. The
typical genus Tenebrio contains black or
brownish, somewhat flattened species,
with a square thorax and deeply ridged
wing-covers. The larvae are known as " meal-worms," and feed
upon grain or meal remnants in barn, stable, or other sheltered

The meal-worm, Tenebrio
molitor.—a, larva ; b, pupa;
c, adult; d to h, structural
details.

THE IXSECT WORLD.

225

spots. They are often bred by bird-fanciers in large numbers,
and only need plenty of food to multiply rapidly. They rarely
do serious injury, but are not pleasant to have around, and may
be easily controlled by cleanliness, supplemented in extreme
cases with bisulphide of carbon. A few other small, brown
forms, among which the species of Triboliuni may be mentioned,
occur under like circumstances, but are amenable to the same
treatment.

Fig. 226.

Triboliuni confusum. — a, adult; b, larva; c, pupa; e, head, with antenna; y, same of

T. fcnugincuiii.

Perhaps the most interesting, and economically the most im-
portant of this series, are the "blister-beetles," or IMcloida;.
The name "blister-beetles" is from a peculiar property possessed
hv them of raising blisters on the human i^kin. This is due to a
substance called " cantharidin," found in the juices of all the
species to a greater or less extent. The species generally used
in medicine comes from Spain, hence the insects are also known
as "Spanish flies." The beetles are rather soft-bodied, with
broad heads, the antennae often knotted in the males, the thorax
narrow and cylindrical, the wing-covers extending well down the
i'ides. Some of the species are brightly colored and banded,
occasionally metallic bronze or coppery, and all of them are leaf-
feeders. Among the common eastern species several attack
potatoes, and of these a yellow and black-striped form, Epicaida
viitata, is known as the "old-fashioned potato-bug." Asters

15

Fig. 227.

Meloidae, or "blister-beetles." — Fig. 227, Spanish fly, Lytta vesicatoria. Fig. 228,
Epicauta vittata: a, second larva; c, rf, coarctata larva, from back and side. Fig. 229,
a and b, true pupa of same, from side and front. Fig. 230, a, grasshopper egg-pod; b,
a few eggs from same : c. triungulin ; rf, carabidoid larva ; e, scarabidoid larva. Fig.
231, adult Epicauta vittata. Fig. 232, Epicauta cinerea. Fig. 233, a, Macrobasis uni-
color ; b, Epicauta pennsylva>iica.

226

THE INSECT WORLD. 227

and other flowers are injured by a black species with gray-edged
elytra, Epicauta cinerca, and among field-crops beets are, after
potatoes, the chief sufferers. The beetles appear quite suddenly
in large numbers, and some species disappear almost as quickly,
while others linger several days. A uniformly black form,
Epicauta pcnnsvlvanica, is often found in considerable numbers
on the flowers of the golden-rod in August and September, while
a uniformly gray species, Macrobasis unicolor, is common on the
false indigo.

The life history is interesting, and the species may be divided
into two series, those living in the nests of burrowing bees and
those living in grasshopper eggs. In the first series the eggs are
laid on flowers, and from each hatches an active little creature
with long legs, prominent jaws, and large head, which is known
as a " triungulin." It runs about the flowers until the proper
kind of bee comes along, gains a foothold on this, and, buried
among the hairy clothing, allows itself to be transported to the
bee nest. There it quits its unconscious host, makes its way
into one of the completed cells, devours first the ^^'g or young
larva, and then completes its own transformations, feeding upon
the stores now without another owner. This type is only
indirectly of economic interest, but is rather injurious than
otherwise.

In the second series the Qg<g is laid either on a plant or on
the ground, but in either case a triungulin similar to that above
described results, and this has the power of existing without food
for several days, while hunting for a grasshopper egg-pod. When
such a one is found its wanderings are over, and it begins feed-
ing at once. When it moults its large head and long legs disap-
pear, and it resembles a Carabid larva, with ovate body, small
head and jaws, and short legs ; it is now in the ' ' carabidoid' '
stage. Again it moults, and now the resemblance is to a
small "white grub," for which reason this has been termed
the " scarabidoid" stage. When all the grasshopper eggs are
devoured, our larva is full grown, ceases feeding, and shrinks
into its own hardened skin, forming a coarctate stage, or
pseudopupa, in which it winters. In spring it emerges from this
covering, is active a short time without feeding, and then enters
the true pupal stage, in which it resembles other Coleoptera. In

2 28 AN ECONOMIC ENTOMOLOGY.

this stage it remains until the proper conditions occur, and then
joins its companions in a seemingly concerted movement to arise
and assume the beetle stage. This uniformity of development
explains the sudden appearance of the insects in large numbers,
and their power to cause mischief is derived from it, since the
farmer does not often realize the nature of the invasion until con-
siderable injury has been done. In the larval stage they are
beneficial, in so far as they feed upon the eggs of grasshoppers,
but it is questionable whether this benefit overbalances the dam-
age they do as adults, and I never hesitate to advise prompt
measures for their destruction. The best of these is a thorough
application of one of the arsenites as soon as the insects appear,
adding milk of lime to make the poison stick better and to dis-
courage feeding. In small patches the beedes can be gathered
in pans early in the day, or they may be driven to a layer of
straw, the latter to be set on fire when the insects become en-
tangled among it. The last is the least desirable of the measures,
though under some circumstances very effective. In all cases,
promptness is essential.

The Rhynchophora, or "snout-beetles," are separated into a
number of families which need not be particularly described here,
but all agree in having a more or less evidently produced beak
or snout, at the end of which the small mouth parts are situated.
The terms " curculios" and "weevils," in addition to that above
given, are rather indiscriminately applied to species of this series.
All the snout-beetles are vegetable feeders in both larval and
adult stages, and, therefore, more or less injurious. Many of the
larvae are internal feeders, and, therefore, white or yellowish,
usually with short, bristly hair, a brown head, and no feet. As
a rule, they are somewhat curved and terminate rather bluntly, a
little like "white grubs," but without the peculiar, large, ter-
minal segment. It will be necessary to restrict our mention to
the most troublesome forms, and the first of these, in systematic
order, is " Fuller's rose-beetle," Aramigus fidleri.

This beetle, which has a short, obtuse snout, and is of a dark,
smoky brown color, lays its eggs in little masses under any sort
of shelter on rose-bushes, and the resulting white, grub-like
larvcC feed on the tender roots of the plants. The insect is,
essentially, a green-house pest, and often weakens the plants, so

THE INSECT irOK/./l

229

as to render unprofitabk' if it does not kill tlum. The beetles
are long-lived, and hide during tiie day on tin- uiulcr side of the
leaves on which they feed. Hence, collecting and destroying
them is the most satisfactory remedy, while the use of a tobacco
extract on the ground will act both as a fertilizer and to destroy
the subterranean larvce.

The clover-leaf beetle, Phytoitoiiius piDictatus, is another (juite
large species, dull brown in color, with indefinitely striped wing-

FiG. 234.

Clover-leaf beetle, Phytonomus puiictalus. — a, egg; b, b, larv;e feeiiing; c, very young
larva ; y, cocoon, its net-like character shown at .?• ,• A, pupa ; /, beetle, on clover-stalk ;
k, same, enlarged ; other letters refer to structural details.

covers, and a short, stout beak. The larva is green, its form well
shown in the figure, and it feeds chiefly at night, eating irregular
holes in the leaves. When full grown it forms a peculiar net-like
cocoon at or a little beneath the surface of the ground and
pupates, becoming adult a few days thereafter. The insects
hibernate in the larval stage, and their injury becomes manifest

230

AN ECO ATOMIC ENTOMOLOGY.

Fig. 235.

Diseased
larva of clover-
leaf beetle.

quite early in the season, often threatening entire destruction of
the crop when they are nearly full grown. Fortunately, nature
has provided a check for this insect in a fungous disease which in
most localities carries off the larvae annually, just
before they mature, leaving only a comparatively
small proportion to perpetuate the species. As
this disease seems to occur in seasons of all kinds,
and irrespective of climatic conditions, it can be
easily introduced into any locality in which the
insects become destructive. Affected larvae curl
themselves round a spear of grass or on the edge
of a leaf and die, first swelling somewhat and
becoming gray in color ; then they collapse and
become black, eventually forming a small, dried,
black mass, utterly indistinguishable in character.
The "white-pine weevil," Pissodes strobi, is one of the most
serious enemies to that tree, and in the more northern States
attacks the leading shoots, in young trees spoiling their shape
completely. The insect has been studied, and a full account

is given in the Fifth Report of
the United States Entomological
Commission, dealing with forest
insects, but no satisfactory reme-
dial measures are proposed. In
parks or gardens small orna-
mental trees can probably be
protected by keeping the leading
shoots sprayed during the spring
with a carbolated soap-wash, to
which Paris green has been
added at the rate of one pound in one hundred and fifty gallons
of water. Other infested shoots should be gathered and burnt.
The report above cited is so full on the subject of forest insects
belonging to this series that only those infesting cultivated crops
need be discussed here.

Early in the season we find on the leaves and stems of rhubarb
a rather long, cylindrical weevil, Lixus co7icavus, with a short
heavy snout, entirely covered by an easily rubbed off, rusty
powder. It is also remarkable for its exceedingly firm texture,

Fig. 236.

White-pine weevil, Pissodes stiobi. — a,
its larva ; b, its pupa.

THE INSECT WORLD.

231

Fig. 237.

making it difficult to pierce with any ordinary pin. It bores
little holes in the leaf and flower stems of the plant, laying an
egg in each, from which hatches in
due time a white, grub-like larva,
which feeds in the plant tissue.
Where the leaves are regularly cut
for market, little trouble is experi-
enced. All old leaves not needed
by the plant should be removed and
destroyed, so that after midsummer
none of the early leaves should re-
main on the plants. If this practice
is constantly carried out no injury
need be apprehended. The natural
food-plant is said to be dock.

In the genus Anthoiiomus small
species predominate, and the colors
are modest, but their powers of in-
jury are by no means in proportion
to their size. One of the most trou-
blesome is the "strawberry-weevil,"
A. signatus, which appears as a small, blackish beetle, with gray
pubescence, when the buds are developing, and lays an ^gg in
each, afterward puncturing the flower-stalk be-
low the bud so as to check development. The
larva feeds upon the pollen in the unopened
bud, and finds it sufficient to attain its full
growth, changing to a beetle in midsummer.
The insect attacks a number of other flowers
in the same way, not even confining itself to
one natural family, and its injury to straw-
berries is of a somewhat intermittent character,
becoming worse for a number of years, then
stopping suddenly for no apparent reason.
Only staminate, or pollen-bearing, varieties are
attacked, and the Sharpless is, perhaps, the
most seriously infested. By planting chiefly
pistillate varieties, the staminate rows may be protected by cheap
coverings until the buds are ready to open, and even if a small

Rhubarb-beetle, Lixus concavus.
—a, its larva ; b, pupa.

Fig. 2:,S.

Strawberry-weevil,
Anthonomus sigtiatus-

232

AN ECONOMIC ENTOMOLOGY.

crop only is obtained on the pollenizers, the main crop will be
safe without protection. Insecticides have not proved markedly
useful in this case.

Other species of this genus have proved more or less trouble-
some, notably A. quadri-gibbus , on apple, but none of these

Fig. 239.

Work of the strawberry-weevil.— a, shoot of strawberry-plant bearing punctured
buds, b ; the egg at c ; larva at d; pupa at/,- at^ an open strawberry-flower showing
the holes eaten by the beetles.

require more attention here, and the next species in order is
Conotrachelus nenuphar, the redoubtable " plum-curculio."
Next to the "codling-moth," this is, perhaps, the most serious
of the orchard pests, and it ranks above it in the difficulty attend-
ing its control. The beetle itself is less than one-fourth of an
inch in length, chunky in appearance, brown, with black and
gray mottlings, and with four elevated excrescences on the wing-
covers. The beetle hibernates and appears in early spring, feed-
ing first upon the unopened buds and afterward upon the young

THE INSECT WORLD.

233

Fig. 240.

Plum-curculio, Conotrachelits iinnt-
phar. — a, larva ; b, pupa ; r, adult ; (/,
beetle at work on a young ])lum, show-
ing a crescent mark.

leaves of plum, peach, apricot, cherry, apple, and pear. When
the fruit has set and become of the size of a marble, the insect
makes a crescent-shaped slit, elevating a small flaj) from the sur-
rounding tissue, and in this it lays an Q^<g. The latter hatches
in a few days, and the whitish, grub-like larva bores at once to
the seed capsule, causing the
fruit to fall from the tree and rot
in the plum, peach, apricot, and
cherry, though, except in tlie
plum, this dropping is not uni-
versal. Apples and pears do not
drop as a result of curculio in-
jury, and, except in a few varie-
ties of ai)ples, the larva is unable
to mature in the fruit remaining
on the tree. In apples and pears
that drop from other causes, the
larva develops freely. By mid-
summer, growth is complete, the
larvae leave the now decayed
fruits and go underground to pupate, changing to the adult, or
beetle, form a short time thereafter. These go into hiding almost
immediately, and are not again seen until the spring following.
Remedial measures in this case have not proved entirely satisfac-
tory. The larva is beyond reach of all insecticides, and can be
destroyed only by persistent and thorough gathering of all fallen
fruit at intervals of a few days throughout the early part of the
summer. Chickens, turkeys, hogs, or sheep accomplish the .same
purpose less completely and lessen if they do not prevent injury.
The beetles may be reached by spraying the trees before the buds
open with one of the arsenites, destroying them before they have
a chance to oviposit. Spraying may be continued after the fruit
has set, to kill the beetle while eating out its crescents. Some
part of the fruit is always injured, though a sufficiently large
percentage to pay for the insecticide application is usually saved.
Jarring the trees every day or two over a sheet or other recep-
tacle has been practised with good success, as the beetles drop
readily and lie quietly for some time, especially early in the day,
allowing themselves to be easily gathered up and destroyed.

234

AN ECONOMIC ENTOMOLOGY.

This is one of those cases where persistent and universal practice
is desirable to obtain the best results.

An allied but larger species of the same genus without the
elevations on the wing-covers is C. crataegi, which attacks the
quince and sometimes does considerable injifry, much as the C.
nenuphar does on the fruits above enumerated. The same
measures are indicated here also.

The 'potato-stalk borer, Trichobaris j-notata, is a small ash-
gray weevil about one-sixth of an inch in length, with a black

Fig. 241.

Potato-stalk borer, Trichobaris trinoiata. — Larva, pupa, and adult.

snout and three small black spots at the base of the wing-covers.
It lays its eggs into the stems and larger branches of the potato,
horse-nettle, Jimpson-weed {^Datura stramonium), and, perhaps,
other Solanaceae, and the white larvae feed there until after mid-
summer, changing to pupae at about the time when the potato-
vines mature, and to adult beetles a short time thereafter. The
beetles remain in their larval burrows during the winter, and may
be easily destroyed by burning the vines immediately after the
potatoes are harvested.

The species of Balanmus are known as nut-weevils, are of
quite large size, clay-yellow in color, and with an exceedingly
long and slender, black beak or snout. By means of this they
puncture the burrs of young chestnuts, the husks of hickory and
walnuts, and the green coverings of young acorns, reaching near
the centre of the nut itself, and placing an &^^ in the hole so

THE IXSECT WORLD.

235

made. The larva hatches and the little wound through which
the ^%% was laid heals so completely that no trace of it is visible

KiG. 242.

Work of the potato-stalk \io\^x,Trichobaris 3-notata, in potato-vines.

in the fully developed fruit. When the nut is ripe and drops to
the ground the larva is full grown, and eats a round hole in the

236

A A' ECONOMIC EXTOMOLOGY.

Chestnut-\vee\ il, Balanimts rectus. — a, from
above ; b, in outline, from side; c, lar\a.

shell through which it makes its way and goes underground to
pupate. Thus it winters, and the beetles emerge in spring when

the nut-trees are in bloom,
'*^' ^'^•^' Considerable injury is

sometimes caused in cul-
tivated chestnut groves,
and the onl}- way to avoid
it is to gather the nuts
systematically as soon as
they fall, and either ship
them at once, or store
them in tight boxes or
barrels, from which the
larvae cannot escape when
they come out. They will then be found at the bottom when
the nuts are removed, and may be easily killed.

In many localities corn is attacked soon after it shows above
ground by insects known as " corn bill-bugs." These belong to
the genus Sphenophonis, and are black or brown, rarely gray in
color, varying from one-fourth to half an inch in length,, with
very thick and hard wing-covers, which are ridged and punc-
tui-ed, as is also the thorax. They hide during the day in the
soil at the base of the corn-plants, and kill them by boring
little round holes in the stem. They are most frequent after
timothy, especially on old sod, or when corn follows sedges or
bulb-rooted grasses. It is in such places that the larvae live
naturally, pupating in fall or early spring, and the beetles, finding
on spring ploughed land that their natural food is gone, attack the
corn, which replaces and is nearly enough like it to be to their
taste. The period of injury is usually short, and by delaying
replanting a little, the new shoots escape attack. Fall ploughing
old timothy sod or sedge-land is always indicated, and will gen-
erally serve to reduce, if it does not entirely prevent, injury.

To this same series belongs the largest of our weevils, the Rhyn-
chophoriis palmarum, or "palm-weevil," which often exceeds an
inch in length and whose fat, white larva, boring in palm, is said
to be quite a delicacy to the taste of the aborigines of Central
and South America.

Much resembling it in shape but hardly exceeding one-eighth

THE IXSECT WORLD.

237

of an inch in length arc the grain weevils, belonging to the genus
Calandra. These are almost cosmopolitan, and infest stored
grains of all kinds. They are black or brown-red in color, quite
slender, and on a very small scale resemble the ' ' corn bill-bugs' '
in sculpture. They can be easily controlled by the use of bisul-
phide of carbon poured on the grain in bins or other receptacles,

Fit;. 244.

Splisiiopho) us ochrciis. — Adult, larva, and work in roots of Scirpus.

covering with canvas or similar material to prevent the too
rapid escape of the fumes which gradually permeate the entire
mass of grain, killing everything in it.

Closing the series we have the bark-beetles, or Scolytids, some
of them called shot-hole borers from the little round holes with
blackened edges which they make in wood and bark. Many
species make prettily-figured burrows between the bark and sap-
wood, while others bore into the solid wood, making longer or
shorter galleries. Mo.st of the species attack forest-trees, and for
them reference should be had to Dr. Packard's work already cited.

238

^jV economic entomology.

These beetles dififer from all the other weevils in their cylin-
drical form and very short snout, which is scarcely more than a
slight prolongation of the head, and they are usually of small
size, most of them not exceeding one-eighth of an inch in length.

Fig. 245.

Calandra granaria. — a, adult ; b, larva ; c, pupa ; d, C. oryza, adult.

Scolytiis riigulosiis, the "fruit-bark beetle," is, perhaps, the
best known, and certainly the most important economically,
attacking deciduous fruit-trees of almost all kinds. The black
parent beetles appear in early spring, and bore little round holes
through the bark to the sap-wood. They then make a central
burrow, on each side of which little notches are made to receive
the soft white eggs. The larvae hatch very soon, and at once
begin to make little burrows of their own, diverging as they
move from the parent channel, and gradually enlarging them as
they increase in size. When full grown they form a slightly
enlarged chamber, in which they pupate, and when they trans-
form to beetles, make their way out through little round holes
in the bark. The whole period of development does not exceed
a month, and there may be several broods during the summer
from the same tree, the numerous galleries eventually girdling
and killing it.

Mi ■

> ■■:a

; ill,*, ¥'''«'/;

' (

^'l

fri4;i\

1^

1'.

1

J

1 •

i ;

■i-^ ^.

'! Ml! -A

hi ♦

A piece of hickory baik, illuairatinjj; tlic w^rk ot ^ci//>^.o ^-o/ii/n/o»o unU .u Ui.\.
natural size.

THE IXSECT WORLD.

239

I""i(;. 246.

Fruit-bark beetle, Scohtus
iiigiilosiis, mucli enlarged.

These insects rarely attack sound, healthy trees, and this is a
peculiarity of bark-beetles in general, though there are many
exceptions. But just as soon as a tree becomes a little weakened
through injury or from starvation, these
little creatures attack it, and then its
doom is sealed, unless vigorous meas-
ures are taken at once. Peach-trees are
especially susceptible to injury, and the
gummy oozings from the little holes
seem to weaken them so rapidly that
they succumb in a short time.

It is good practice to keep orchard
trees in the best possible health and
vigor at all times to enable them to resist
naturally the attacks of these insects,
but if one does become seriously infested
it should be at once cut out and burnt.
It is certain to die in a short time, and .

it is a constant menace to surrounding trees from the abundance
of specimens which will be produced, ready to attack others at
the least sign of weakness. Where a slight infestation is noticed
on a tolerably healthy tree, it should be closely examined to
ascertain the original source of weakness, and when this is re-
moved the tree should be stimulated by means of appropriate
fertilizers, and the trunk kept covered by whitewash to which
Paris green has been added. Strong whale-oil soap-suds will
answer the same purpose, and a little crude carbolic acid will
add to its effectiveness. In all cases the application should be
thorough, and should be kept intact until the tree has fully
recovered and is able to take care of itself

The same line of treatment is adapted to other bark-beetles,
varied according to the differences in life history.

To recapitulate in a general way, beetles and their larvae are
mandibulate and chew their food ; therefore, whenever they feed
openly upon plant tissues, they may be killed by arsenical sprays.
Internal feeders must be dealt with as indicated by their life
habits, but we must look rather to preventive than to remedial
measures in such cases.

.140

AiV ECONOMIC ENTOMOLOGY.

CHAPTER VII.

THE LEPIDOPTERA.

Butterflies and Moths.

Under the term Lepidoptera are included those insects popu-
larly known as butterflies and moths, in which the wings and
body are more or less clothed with scales. These scales often
differ greatly in form and size even in the same insect, and yet
more in different groups, so that a certain family or series may
show types peculiar to it alone. Oddly enough, there is some-

FlG

Fig. 249.

Scales on wing of butterfly.

Head of a moth. — The
tongue uncoiled at a; seen
from side, partly coiled, at
b ; the appearance of tongue
under a lens at c.

times a difference even in the sexes, certain kinds of highly
developed scales occurring on the wings of the male only,
usually confined to limited areas and sometimes concealed by
folds.

In this order the adult insects are harmless throughout, capable
of feeding only upon liquid food by means of a tongue which
is usually coiled like a watch-spring on the under side of the
head between the palpi. In some instances it is wanting, and
on the other hand sometimes becomes enormously developed,
reaching a length in some species of from five to nearly seven

THE IXSECT WORLD.

241

Fig. 250.

inches. Many of the Lcpidoptera are useful in pollenizing
flowers, some, indeed, depending entirely upon them for their
continued existence, but, on the other hand, the caterpillars, as
the larvie are usually called, are among the most troublesome
and injurious insects with which the agriculturist has to deal.
The transformation in this order is comj^lete, and a greater
difference than that between caterpillar and butterfly can hardly
be imagined ; while in the chrysalis or pupa we have a quiescent
period where scarcely even the form of the future insect is indi-
cated, and when it is absolutely incapable of motion.

Broadly, the order is divided into butterflies and moths, or,
more accurately, the Rhopalocera and Heterocera. Rlwpalocera
are those in which the antennae, or
feelers, terminate in a more or less
distinct knob or club at the tip, and
in which at least the front pair of
wings are elevated or vertical when
at rest, so that the upper surfaces
touch. The Heterocera, on the
other hand, have feelers, or anten-
nae, of many different kinds, but
never in our fauna distinctly
clubbed. The wings when the
insect is at rest are horizontal,
folded on the back or close to the
sides, oblique, roof-like, or spread
out flat, but never habitually ver-
tical. In general it may be said
that the butterflies are on the
wing during the day, and fly dur-
ing the night only in rare in-
stances ; moths, on the other hand,
are night flyers, as a rule, though there are many exceptions,
and a number of species occur commonly during the day.

The butterflies separate readily into groups based on the char-
acter of the feet and the situation of the antennae. What may
be called for convenience the " true butterflies " are distinguished
by having the feelers set close together on the top of the head,
the latter being proportionately rather narrow. The antennal

16

Antennae in Lepidoptera. — a,
clubbed antenna of butterfly ; b, c,
variations in form of club; d, prismatic
and fusiform ; e, ciliated ; _/", bristle-
tufted ; g, doubly bipectinated.

242

AN ECONOMIC ENTOMOLOGY.

club is abrupt at the tip and not drawn out into a hook or
recurved. In the skippers, or Hesperids, the head is broad, the
eyes are comparatively small, the feelers are widely separated,
set close to the eyes, and terminated by a pointed tip which is
often recurved or hooked.

A large series of the true butterflies is distinguished by having
the anterior pair of feet more or less aborted or imperfect, and
these, the "brush-footed " butterflies, are classed in two famihes.

Fig. 251.

Fig. 252.

yCC-

Ir

a, head of Papilio, show-
ing where anteiinse are in-
serted ; b, same of an
Hesperid.

a, foreleg of a brush-footed butterfly entirely
aborted ; b, of Lyctziia, male, tarsus one-jointed.

the NymphalidcB, containing moderate-sized or large species, and
the Lyccenidis, containing small species, in which the colors are
blue or coppery, or have the under sides marked with fine,
thread-like lines. They are the "blues," "coppers," and
' ' hair-streaks. ' '

Among our most common species of the first family is the
"milk-weed butterfly," Danais archippus, quite a large red-
brown insect, with the wing-veins broadly black marked. It
becomes abundant in late summer and fall, and its caterpillar,
green in color, marked with black lines, and furnished with rather
long, black, hair-like tentacles, may be often seen feeding upon
milk-weeds. This species will serve to typify the family to which
it belongs, and is easily raised by any one curious to watch its
transformations. If the caterpillar be confined with a sufficient
supply of fresh leaves, it will grow to about an inch and a half in
length, will then fasten itself by means of its hind feet to a little
pad of silk, and will change to a chunky, bright-green chrysalis,
or pupa, marked with small golden spots, one of the prettiest
objects that can be imagined. In a few days the color will be-

THE INSECT WOKLD.

243

come darker, finally brown or blackish, and then the butterfly-
will emerge. This is not an injurious insect, and is only referred

Fig. 253.

Milk-weed butterfly, Danais arcliippus,&nA its transformations. — A, a, egg enlarged
thirty diameters ; b, very young larva, showing how the tentacles are folded ; <:, egg,
natural size, on a leaf; B, full-grown larva ; C, chrysalis ; D, male butterfly.

to here because it is easily raised and common throughout the
country, — in fact, has spread all over the globe.

244 ''^^^- ECONOMIC ENTOMOLOGY.

We have many species of considerable size belonging to the
genus Argynnis, which resemble each other more or less by

their tawny upper sides
Fic-.. 254. marked with black spots,

and by having the under
sides more or less marked
with silvery blotches, es-
pecially on the hind wings.
None of them are injurious,
the larvae feeding upon vio-
lets. In the genus Grapta
there are species with
C;a/./<j/.r<'.cr'"-.'^\viiiKsofTightsirie detached strougly and irregularly

to show under side; this is almost like G. angulatcd and tOOthed
comma. ■ ■ 111

wmgs, quite dark brown
in color, with irregular black or blackish blotches, spots, and
lines, and a little silvery mark resembling a comma or semicolon
on the hind wings beneath. Of these the caterpillar of G. comma
feeds upon the hop-vine, although it rarely does any serious
injury. It is reddish or yellowish in color, with a black head
and black branched spines, and forms an angular chrysalis which
is suspended by the tail. The chrysalis is yellowish green in
color, with prominently marked segments, and has the thorax
produced into a somewhat acute process.

Another very common, almost cosmopolitan butterfly, is the
Vanessa antiopa, popularly known as the "mourning-cloak."
It is of a very dark, rich-brown color, with a broad yellowish
border on both wings. It winters in the butterfly stage, and
may often be seen on warm days in midwinter, fluttering about in
the woods, while it is the earliest of the butterflies to make its
appearance in spring. The caterpillars feed upon quite a variety
of plants, notably willow and poplar, and often in great colonies.
When full grown they are two inches or more in length and black,
with red-marked, branched spines. The chrysalis is suspended
by the tail, and of a somewhat mouse-gray color, the segments
marked with acute spines. This may under circumstances be-
come a troublesome insect, but it is easily controlled, either by
arsenical poisons, as the caterpillar feeds exposed, or by hand-
picking, which is easy because of the gregarious habit when

THE INSECT WORLD.

245

younq;. A nuinber of other common species belong in this
family, but, as they do not feed upon cultivated plants in suffi-
cient numbers to attract attention, they need not be further
considered.

Fig. 256.

Larva and chrysalis of I'aiirssa antiopa.

Quite early in spring we may see, fluttering along the road-
sides, little blue butterflies expanding less than an inch when the
wings are spread, and without prominent markings of any kind.
These belong to the family LyccenidcB, usually to the typical
genus LyccEua, and from them the term "blues," as a popular
name, has been derived. Later in the summer we find com-
monly bright coppery butterflies, not much larger than the
" blues " already spoken of, and on the upper surface, especially

Fig. 258.

Chrys,o[>tiaiius t/ior. — Male and female.

of the fore-wings, are black spots varying in size and arrange-
ment. To these the name "coppers" has been applied, and
they belong to the natural genus Chrysopha)ius. The genus
TJiecIa contains species that run larger than either of those pre-
viously mentioned, many of them sombre in color and marked
on the under side by fine, hair-like streaks, differing in arrange-
ment and not always present. These are called "hair-streaks."

246 AN ECONOMIC ENTOMOLOGY.

The hind wings are often furnished with one or two pairs of
slender, thread-like tails, easily broken off if the insects are care-
lessly handled. None of the members of this family are injurious,
and the somewhat slug-like caterpillars are not often seen.
Fenesica tarquinius looks like one of the " coppers," and is pe-
culiar in that its larva feeds on the woolly plant-lice often found
on beech and other trees. It is the only butterfly larva in our
country which is known to be predaceous.

The family PapilionidcE contains six-footed butterflies, the
anterior feet being perfectly developed in both sexes, and here
the antennae are set rather close together at the base. It includes
our largest and brightest species, the most prominent of them
being known as "swallow-tails," There are two groups, the
first containing smaller species, which are white or yellow in
color, the hind wings without tails, but furnished with a fold
along the inner margin, forming a groove, in which the abdomen
lies. These are arranged under the term Pierince, and contain
as typical forms the common cabbage butterflies. The most
abundant and injurious of these is Pieris rupee, an insect imported
many years ago from Europe, and which has now spread over
the largest part of the United States and Canada. The wings
expand about an inch and a half, are white or with a creamy
tinge, with a single black spot in the fore-wings of the male, and
two similar spots in those of the female. There is also a little
black patch at the apex, and on the under side the wings are
usually darker and a little powdery. These butterflies appear
very early in spring, emerging from chrysalids that have hiber-
nated, and lay their eggs upon almost any of the cruciferous
weeds. They are not particularly choice, but perhaps the com-
mon Barbarea vulgaris is about as often selected as any in the
Middle States, because one of the first to make its appearance.
The first brood comes to maturity in less than a month, and then
eggs are laid on early cabbage-plants. Soon irregular holes
appear, first in the outer leaves, then in the head itself, and little
piles of dirty-yellow excrement may now be found everywhere
among the folds. The caterpillars themselves are velvety green
in color, almost like the cabbage-leaf, and, as they lie rather
closely to the plant tissue, are easily overlooked until a little
practice is gained in searching for them. They become more

I'^IG. 260.

Fig. 265.

Fig. 261.

Fig. 264.

Fig. 259.

Fig. 262.

Fig. 259, Thecla strigosa. Fig. 260, Pieris rapes, male. Fig. 261, Ptois raptT, female.
Fig. 262, a, larva; b, chrysalis of Pieris rapce. Fig. 263, Pieris prolodice, male. Fig.
264, Pieris prolodice , female. Fig. 265, larva and chrysalis of P. prolodice.

247

248 AN ECONOMIC ENTOMOLOGY.

abundant as the season advances, and late cabbage often suffers
seriously in some localities. By all odds the best remedy is
spraying with the arsenites, at the rate of about one pound in
one hundred and fifty gallons of water. A great many other
remedies have been recommended, and some of them are un-
doubtedly useful, but nothing is so satisfactory and cheap as the
arsenite, and without gross carelessness there is not the slightest
danger in the application. The cabbage heads from within, —
that is to say, the leaves unfold from the centre of the head and
do not fold together to form it ; therefore, whatever poison is put
upon the plant can fall only upon the outer leaves, and not a
particle gets into the head itself The amount used to a single
cabbage-plant is so minute that in order really to poison a man it
would be necessary for him to eat about a dozen heads, outer
leaves and all, and if death then resulted I would be inclined to
attribute it rather to the cabbage itself than to the Paris green or
other arsenite employed. The larvae succumb to the poison very
readily, and by making the application early in the season the
later broods may be materially reduced in number. In ordinary
farm practice the heads are cut out and shipped, and in prepar-
ing the cabbage for food, the outer leaves of these heads are
generally taken off by the housewife because more or less bruised
or injured, before they are cooked. Chemical analysis has shown
that on a head so prepared, within a week after a heavy applica-
tion of Paris green, not a trace of arsenic remained. As a matter
of fact, the use of Paris green as against the insect is quite
common, although little is said of it, to avoid exciting prejudice,
and I have yet to learn of the first case of arsenical poisoning
from eating cabbage so treated. From New Jersey southward
and westward, one of our native species, P. protodice, becomes
more common and assists its imported relative in making havoc
among the cabbages, but this also may be easily controlled by the
measures above detailed.

We find flying abundantly in our fields, and more common
among clover, a bright, sulphur-yellow butterfly about as large
as the P. rapes, with a single black spot on the fore-wings, and a
broad black outer margin to both pairs. On the under side the
hind wings have a central orange spot, often with a slight silvery
tendency. These butterflies belong to the genus Co/ias, and the

rilE INSECT WORLD.
Fig. 255.

249

Fig. 266.

Fig. 257.

Fig. 255, mourning-cloak butterfly, Vanessa antiopa. Fig. 257, Lyccena pseudargiolus. Fig. 266,
Colias philodice, male. Fig. 267, same, female. F"ig. 272, Nisoniades juvenalis.

250

AN ECONOMIC ENTOMOLOGY.

common eastern species, extending- westward to the Rocky-
Mountains, is C. philodice^ whose larva feeds upon clover. It is
a green caterpillar somewhat similar to the " cabbage- worm,"
but although it may be quite abundant, rarely does injury enough
to be noticed. As a rule, the larva is rather difificult to find, even
where the butterflies are abundant, and practically no measures
need be taken against it.

In the sub-family Papilionina; we have in our country only the
typical genus Papilio, containing species abundant enough to
become of economic importance. The most common of these is

Fig. 268.

Papilio asterias, male.

P. asterias, a black " swallow-tail," expanding between two and
three inches, the hind wings tailed and excavated on the inner
margin, so that the abdomen is free, not enfolded in a groove.
The male is somewhat smaller than the female, and has a diag-
onal row of yellow spots crossing the fore-wings outwardly and
the hind wings nearly across the centre. Near the outer margin
of both wings there is a row of yellow, lunate spots, and at the
inner angle of the hind wings is a peculiar, eye-like spot, just at
the margin. The female has the inner row of yellow spots very
much reduced, sometimes altogether wanting, but on the hind
wings the space between the faint series of yellow spots and the
outer lunules is beautifully powdered with metallic blue scales.
These butterflies lay their eggs on carrots, parsley, and other
plants of the same natural family, and from them hatch bright

THE INSECT WORLD.

251

green caterpillars with broken black bands. A peculiarity of
tliis kind of caterpillar is that when touched or irritated in any
way it shoots out from between the segments close to the head a
forked, orange-colored process, which emits a very disagreeable
odor, and this is its only means of defence. No trace of the pro-
cess is visible when the insect is at rest, and the horns are with-
drawn just as soon as irritation ceases. When the caterpillar is
full grown it leaves the plants upon which it has fed and travels
to any convenient point in the vicinity where it can pupate. This
pupa, or chrysalis, is fastened to a little silken pad by the tail,

Fig. 269.

Papilio aslerias .—'W\iX\xx^ larva and pupa.

but is also sustained by a silken band in front of the middle, so
that it is said to be girthed, and this same type we have in all the
members of this family. These caterpillars are rarely abundant
enough to become troublesome, but if they are, hand-picking is,
perhaps, as good a remedy as any. They are quite prominent,
and, therefore, easily and rapidly gathered, checking their injury
immediately and completely. When they are small, spraying
with the arsenites will answer, provided it be done thoroughly.

Another species is P. phile^wr, of about the same size, black,
without the yellow spots through the centre, but with the upper
surface overlaid with greenish, powdery scales, which give the
insect a metallic lustre in certain lights, and this varies according
to the angle at which the light strikes the wings. The cater-
pillars feed upon vines of Aristoloc/ua, or " Dutchman's pipe,"
which they sometimes injure considerably. They are dull
brownish red in color, with long, fleshy filaments on the seg-
ments, and when irritated also extrude fleshy horns such as

252

AN ECONOMIC ENTOMOLOGY.

already described and for the same purpose. The measures
recommended for the parsley caterpillar may also be adopted
against this insect.

The largest of the common northern "swallow-tail" butterflies
is the P. turmis, which expands from three to six inches, and is

THE INSECT WOKI.D.

253

bright yellow in color, with transverse black bands. Towards
the South and West, occurring rarely, however, as far north as
Canada, wc have a form of the female which is black, but maybe
distinguished by its large size from our normally black species.
The caterpillar is green, and distinguished by having two black,
eye-like spots on the anterior segments. It feeds on a number
of different plants, but does not become economically imj^ortant.
In P'lorida, P. cresphontcs is abundant, and its caterpillar is
known as the "orange dog," from its peculiar appearance and

Fig. 271.

The orange dog, caterpillar of Papilio cresphontes, with osmateria, or scent-organs,
extended ; the detached figure shows the anterior segments normally retracted.

habit of feeding upon orange-leaves. The butterfly is even larger
than the hirnus, and is black, with a broad diagonal band of
contiguous yellow spots extending from the tip of the fore-wings
towards the base, reaching the inner margin very near to the base
of the hind wings. There is also a band of yellow spots near the
outer margin, which are especially prominent on the hind wings,
and a yellow spot occupies the centre of the broad, lobed tail.
The caterpillars are prominent, as already stated, and orange-
growers consider them among the greatest troubles of the young
trees, especially in the nurseries, where a single sj^ecimen may
defoliate a shoot in a little time. Hand-picking on small trees is
a feasible and satisfactory remedy, and another is to capture the

254

AN ECONOMIC ENTOMOLOGY.

butterflies on the flowers which they frequent during the middle
of the day. Mr. Hubbard has suggested shooting them with
cartridges loaded with sand, and that can easily be done during
mid-day from a veranda or other shelter when the butterflies
hover around the flowers near by.

The "skippers," or Hesperidcc, differ from all the preceding
by the broad head, clothed with bristly hair, and by the widely
separated antennae, or feelers, the club being also terminated by
a more or less marked and recurved slender booklet. They are
small or moderate in size, and get the common name from their
jerky habits of flight, usually along roads, and practically con-
fined to low herbage. There are two rather well-marked, though
by no means sharply limited sections, distinguished by color, the
first containing dark, blackish or sombre brown types, and the

other tawny yellow forms.
Fig. 273. The former is represented

by the species of Nison-
iades and its immediate
allies, and the latter by
the genus Pamphila and
allies. In this latter se-
ries the fore-wings are
much more pointed than
in the other, and the body
is proportionately more
robust. None of the species, so far as I am aware, are of eco-
nomic importance, though our largest species, Megathymus
yuccce, does some injury by occasionally boring into the roots of
the yucca plant. These insects have been considered intermedi-
ate between the butterflies and moths, and many species have
the habit of elevating the front wings only, the hind wings being
held horizontally.

The first of the Heterocei-a to be considered here are the
Sphingid(S, or ' ' hawk-moths, ' ' and these obtain the common
name from their habit of hovering about flowers, and their rapid,
darting motions. Most of them fly just about dusk, visiting
deep flowers like the "evening primrose," "petunia," or even
" Jimson weed," and they succeed in reaching the very bottom
of these by means of an unusually well-developed tongue. They

Pamphila ethliiis.

THE INSECT WORLD. 255

gather their iuod while hovering, inserting the i)roboscis into the

nectaries, but rarely alighting. The antennae are prismatic and

256 ^A' ECONOMIC ENTOMOLOGY.

spindle-shaped, and terminate in a little, recurved hook. The
body is robust and well developed, supported in flight by means
of stout, though rather narrow, pointed wings. The caterpillars
are peculiar in having a curved horn on top of the last segment,
or in its place a hard, glossy, eye-like spot. When at rest, some
of them have the habit of elevating the front part of the body
and curling the head under a little, giving them a fancied resem-
blance to a Sphinx, and from this the scientific name has been
derived. A very good example of a typical sphinx caterpillar is
found in the large green species, the sides with oblique, lateral,
white stripes, which is often found upon potatoes and tomatoes,
occasionally doing considerable injury. The anal horn is quite
often believed to be venomous, and all sorts of stories are told of
people having been poisoned or stung ; it is even said sometimes
that a stream of poison is thrown from the end of the horn for
some distance. As a matter of fact, nothing can be more harm-
less than these caterpillars ; there is no poisonous secretion
connected with the horn, and they can be handled with absolute
safety. This same type of caterpillar also attacks tobacco and
other Solanacece, and, when full grown, goes underground and
changes to a mahogany-brown pupa an inch and a half to two
inches in length, wuth a peculiar handle-like process attached to
the head, which forms a covering for the future tongue. This
has given them the name "jug-handle grubs" in some localities.
The adults, when they emerge, expand from three to five inches
or more, and are ashen-gray in color, the fore-wings with a
little white spot near the centre, and crossed by irregular darker
lines, the hind wings banded with black and white, while along
the sides of the abdomen are five large yellow spots. This is the
Sphinx {Protoparce) caroliiia, which may be accepted as typical
of the series to which it belongs. An allied species, Protoparce
ccleus, feeds on the same kinds of plants, and resembles the
Carolina rather closely, except that the yellow of the abdomen
is paler, the lines on both wings are rather more distinct, and
the insect is a little larger ; but the differences are not great, and
need not be further detailed here. Other species of sphinx
caterpillars are found on a variety of other plants, but they do
not often appear in noticeable numbers, being much subject, from
their large size, to the attacks of birds and parasitic insects ; so,

THE INSECT WORLD. 257

«

except for tlic species already mentioned, nature herself keeps
down the insects to a reasonable number.

Another series of this same family is more brightly colored,
with the wings angulate, dentate, or only a little sinuate at the
outer margin, and of these we have several species that attack
the vine. The caterpillars are rather more clumsy than those of
the preceding series, and the head is often retracted into the
enlarged thoracic segments. The horn is frequently wanting and
replaced by a shining, usually blackish, eye-spot. These are
known as "hog-caterpillars," and often appear in numbers
sufficient to cause more or less injury in vineyards. The adults
are brightly colored, either greenish with darker, blotchy mark-
ings, or reddish with brown markings, or a combination of olive
green and rusty brown and gray. The figures herewith given
illustrate the more common species, and as their habits are much
the same, no special description of each is needed.

On the elm-tree we sometimes find a green caterpillar, the skin
a little roughened, with the typical sphinx anal horn and, in addi-
tion, four little horns on the anterior segments. This is the larva
of Ceratomia amyjitor, or, as Dr. Harris called it, much more
appropriately, qiiadricornis, which means four-horned. The
moths produced by this caterpillar may often be found in mid-
summer on the trunks, and are dirty yellowish gray, streaked
with blackish, and with white discal spots.

Sometimes we find, flying around flowers in bright sunlight,
exceedingly active little creatures that at first sight resemble
humming-birds, and are frequently considered such. If they be
captured, however, we see that they are brilliantly colored moths,
which have received the common name "humming-bird hawk-
moths. ' ' They usually have the fore-wings quite sparsely clothed,
sometimes nearly transparent, while the body is covered by rich
coppery or other metallic-colored scales.

The caterpillars in this family are all external feeders, and
usually so large and prominent that they can easily be seen. In
most cases, therefore, the simplest remedy is hand-picking, but
when this is done no caterpillar should be destroyed which is
covered with little, white, egg-like bodies, for these are the
cocoons of parasites which do much to keep the insects in check.
Where the larvae are abundant enough to make hand-picking

17

258

AN ECONOMIC ENTOMOLOGY.
Fig. 275.

Fig. 275, Philampeliis paiidorus. Fig. 276, Philampeltis acliemou, larva. Fig. 277,
Philampelus achemon.

Fk;. 27S.

Fig. 2S0.

Fig. 27b, Melittia ci-to. ilu- Mniasli-liuixr : a, b, moth, the wings sjjread and at rest;
c, young larvse ; d, cocoon with the enii)ty pupa shell projecting. Kig. 279, squash-
borers, full grown, in a section of si|uash-\ine. I-"ig. j.So, imported currant-borer, Sfsia
lipuliforiiiis : larva, adult, and pupa skin projecting from the cane.

THE INSECT WORLD. 259

impracticable, any of the arsenite.s may be employed. The
attempt has been made, not without a fair degree of success, to
protect tobacco plants by killing off the moths while feeding in
the flowers of the " Jimson weed," a few drops of a poisonous
solution being placed in the bottom of each flower. It is perhaps
questionable whether the results obtained justify the method
from a practical stand-point, and the direct application of poison
to kill the larvie is, all things considered, the most satisfactory.

Following the hawk-moths in our lists, but not in the least
related to them structurally, are the clear-winged moths belong-
ing to the fuiiily Scsiidcc. They are slender bodied, with quite
long antenuce, the wings narrow, often without scales, the colors
metallic or at least glistening, and usually bright and contrasting.
They often resemble and are considered wasps or hornets from
their appearance, the more so because it is quite usual for them
to have the abdomen banded with yellow. These creatures are
the parents of borers that are among the most injurious to culti-
vated plants.

First in the series is the " squash-borer, Jlfeliftia cdo. This is
readily recognized in the adult stage by the opaque, greenish
fore-wings, and by the unusually large, thickened hind legs,
tufted with black and orange, giving the insect a characteristic
appearance, different from any other common species. It may
be found during late spring or early summer hovering about the
squash or other cucurbit plants during the day, but in the even-
ing and during the night resting exposed upon the leaves. It
lays its eggs preferably on the vine just at the surface of the
ground, if the soil is light even a little below, but it is by no
means confined to this point, and may lay them anywhere, even
on a leaf or leaf-stalk. They are brown in color, disk-like, and
have a very brittle shell. The larvae when hatched are white or
nearly so, with a small brown head, a full complement of legs,
and at once bore into the stem of the vine. Preferably they live
just at the surface of the ground, really eating very little of the
plant, but rather they suck the juices, causing its enfeeblement
and ultimate death. When full grown in midsummer the larva
goes a short distance underground and forms a very tough,
parchment-like cocoon in which it rests until the year following.
In spring the pupa, by means of its chisel-like head-case, cuts a

26o

AN ECONOMIC ENTOMOLOGY.

circular lid from the cocoon, wriggles its way to the surface, and
through it into the open air. This has long been a pest to
squash- growers, and the usual remedy is cutting them out when
the wilting vines denote their presence. This is quite practical,
but has the disadvantage of being very slow, besides having a
tendency to injure the vines if the cutting is unskilfully done.
Care must be taken to cut only longitudinally, while the wounds
should be rubbed with dry soil and covered with earth to facilitate
healing. Covering the joints to induce rooting is advantageous,
because it gives new sources of supply for plant food ; so that even
if the vine be entirely severed at the original root, it may mature
fruit from the suckers. Where squashes are raised on a large
scale, the best method is to trap the insects by a first crop of
some summer variety, preferably crook-necks. These grow
rapidly, and the moths readily lay their eggs upon them, the
plants continuing to do well even when infested by the larvse,
and maturing an early crop of fruit. The late squashes, Hub-
bard or marrowfat, may be planted when the summer varieties
are well under way, and by the time they are large enough to
be attractive to the moths, most if not all the eggs will have
been laid, and they will be practically exempt. As soon as the
late varieties need the ground the sum-
mer variety should be carefully removed,
the plants being taken out entire and
destroyed, and with them the brood of
contained larvae. In other words, the
summer squashes are to be used as a
trap crop to protect the Hubbard, mar-
rowfat, or other main, late variety. It
should be said that in the Central and
Southern States there are two broods
of these insects, and even on Long
Island, New York, a few specimens are
occasionally found in September. Vigor-
ous war on the first brood, however, by
means of traps will prevent injury from
the second.

Blackberries are often attacked by a similar larva at the surface
of the ground or a little below it, boring sometimes a little dis-

Benibecia marginata.
male ; b, female.

THE INSECT WORLD.

26]

Fig

tance up or down the cane or completely around it, for which
reason it has been called the "blackberry crown-borer." Signs
of its presence are the sudden wilting and rapid death of new-
shoots, and it comes to maturity in early September of the
second year of its life, forming a pupa in the stalk itself The
resulting moth, Bcmbecia viarginata, is black, very little marked
with yellow, and the only satisfactory remedy is cutting out and
destroying the larva as soon as its presence is indicated by the
wilting leaves.

Perhaps the best known of all belonging to this series is the
"peach-borer," Sannina cxitiosa. This is the pest of peach-
growers all over the country, and the larvae live between bark and
wood a little below the
surface of the ground in
a mass of gum and woody
material. They first
make their appearance
after midsummer, and
become about three-
fourths of an inch long
before winter sets in. In
spring they resume feed-
ing, attaining a length of
a little more than an inch,
then spin a cocoon of
silk and bits of chips
covered with gum, and
change to a pupa. In
this stage they remain a
few days and then emerge
as moths. The sexes are
very unlike, the males
black, with narrowly yel-
low-banded abdomen,
and entirely transparent wings ; the females much larger, the
fore-wings almost blackish brown and entirely covered with scales,
the abdomen black, with a broad orange band at about the
middle. The eggs are laid on the bark near the surface of the
ground, and the larvae hatch after midsummer in time to do con-

The peach-borer, Satuiuia exitiusa : male
female below ; both enlarged.

above,

262 AN ECONOMIC ENTOMOLOGY.

siderable feeding before winter arrives. "Worming" peach-
trees, or cutting out the larvae, is a recognized method of getting
rid of these insects, and has the advantage of being effective, if
thoroughly done. It has the disadvantage of gashing the trees,
and sometimes causing a considerable amount of injury before
the insect is found. If carelessly done a few will escape, and
sooner or later the tree becomes girdled at the base, or so
weakened that it proves attractive to bark-beetles, who complete
the work begun by the borers. Our task is to keep the insects
out if possible, and the best method is to cover the bark with
some material upon which the insect cannot lay its eggs or through
which the young larvae cannot penetrate. On old trees white-
lead paint in boiled linseed oil is about as good as anything, but
it should not be used on young trees, nor should turpentine be
used to thin out the lead in any case. On younger trees white-
wash thoroughly applied and kept on from quite early in the
spring until after midsummer will answer the same purpose, but
as this washes off readily, it must be renewed as often as the
coating becomes imperfect. Quite a satisfactory method is to
wrap newspapers or tarred paper around the lower two feet of
the trunk, hilling up against it at the base and tying at the top.
This must be replaced yearly, but is an effective protection when
well put on. Fine wire netting will answer the same purpose,
and has the advantage of being more lasting ; or an application
of cement mixed with skim-milk, applied early in the season
and maintained until midsummer, will serve. Anything, in fact,
that forms a mechanical protection to the tree will answer,
and this is the most satisfactory method of keeping out borers
generally.

There are other species of this family boring in maple, and
their empty pupa shells may often be seen sticking out of the
bark ; and so plum, pear, and a great variety of other trees are
sometimes attacked. Where maples are to be protected, the
whitewash affords the best hope of success, unless wire netting
much finer than the ordinary mosquito screening is employed.
Sesia acerni, the "maple clear- wing," is a slender-bodied little
creature, prettily marked with red and yellow, and would be
able to oviposit through the meshes of an ordinary mosquito
screen without trouble.

THE INSECT WORLD.

263

Currants and lilacs arc frequently attacked by borers of this
family, and on currants considerable injury is sometimes done by
Sesia tipuliformis. Here the best remedy is to cut out the dead
stalks in spring, just as soon as leafing out shows where the
attack is located, and every wilted shoot seen at any time should
be cut off at once below the point affected. The cut stems must,
of course, be burnt inmiediately. An occasional liberal pruning
back will prove useful in keeping down the insects, and is some
times a benefit to the plants as well.

As a whole, we may say that our methods of treatment of this
family are in the nature of prevention where the species attack
trees, and cutting out where they attack shrubs or herbaceous
plants.

Grape-vines, especially in city gardens or in villages, are often
attacked by light-brownish caterpillars with black dottings,
which are sometimes so abundant as actually to defoliate them.
They become nearly an inch

and a half in length when full ^'^- ^^3.

grown, then bore into any soft,
rotten, or e\'en comparatively
sound wood, where they pupate
and eventually emerge as active
httle moths, expanding rather
more than an inch, with black
fore-wings having two pale yel-
low blotches, and black hind
wings with two white spots, of
which that near the base is
much the largest. The shoul-
der tippets are yellow, and the
insect is active during mid-day,
hovering about the vines in the
brightest sunshine. It is the Alypia odo-maadata, or 8-spotted
forester, common throughout the Eastern and Central United
States on wild as well as cultivated vines and Virginia creeper, but
rarely troublesome, except near or in cities or towns. The cater-
pillars feed quite exposed, and may be easily destroyed by means
of the arsenites. In city gardens, pyrethrum in the form of a
spray, two ounces to a gallon of water, will prove sufficiently

Alypia octo-ynacidata, 8-spotted forester.
— a, larva ; b, an enlarged segment ; c,
the moth.

264 AN ECONOMIC ENTOMOLOGY.

effective, especially if applied while the caterpillars are still quite
small.

Arranged in the same family, Agaristidcc, are several similar
caterpillars, producing quite different moths, but amenable to the
same methods of treatment. One species, the larva of Psycho-
morpha epimenis, folds the edges of^ the leaves and lives in the
little pocket so formed ; but they are usually so rare that they can
hardly be termed injurious.

In that part of the Southern States where the "moon-vine,"
Ipomaa, flourishes, it is often attacked and sometimes defoliated
by a yellow, hairy caterpillar, which appears in considerable

Fig. 284. Fig. 285.

Psychomorpha ephnenis.— Male insect Iiuc/iyoviia ipomcecp.

and larva.

numbers. When this is full grown it denudes itself of hair, and
with it and a few threads of silk forms a bright yellow cocoon,
from which issues in due time a wasp-like moth expanding
nearly an inch, with narrow, white-spotted black wings, and a
black, bright red or yellow banded abdomen. This is Ejuhro
inia ipom(£ce, which flies rather heavily and clumsily during the
middle of the day in bright sunlight. As against this insect the
arsenites are indicated, or, where only a few plants are to be
protected, hand-picking may be resorted to.

In vineyards there may be often seen feeding on the under
sides of the leaves little, black-spotted, yellow, somewhat hairy
larvae, less than half an inch in length, ranged side by side as
closely as possible, and retreating as they eat until a leaf is com-
pletely skeletonized. When this kind of larva is full grown it
spins a white, flattened cocoon, in which it changes to a pupa
and from which it emerges in due time as a little, narrow-
winged, black moth wearing a red collar. This is the Harrisina

THE IXSECT WORLD. 265

americana, and certain varieties of grapes are occasionally in-
jured by its larva. Feeding in colonies, as it does, the insect is
easily checked by local applications of the arsenites.

Grape-leaf on which larva:- of Hai > in'iia aviei ica>ia are feeding.

We now enter into a series of species the caterpillars of which
are known as " woolly bears," from the fact that they are all
clothed with long hair. In some cases this hair is so dense that
the body of the caterpillar itself cannot be seen at all, and all
these are of the Ardiid series. They spin a small quantity of
silk only, and use the hair with which they are clothed in con-
junction with it to form the cocoon. Under the microscope it
may be seen that it is furnished with small spurs or branches, by
means of which the insect is able to produce a felt-like material,
needing only a small quantity of silk to hold it together in a
tissue sufficiently firm for its purpose. Perhaps the majority of
the caterpillars of this series feed upon low plants, and frequently
it does not matter much what. Plantain seems to be a common
food for many species, but they eat grasses as well, and, indeed,
almost anything. They are often found in gardens attacking
lettuce and cabbage, and on cabbages they are sometimes trouble-
some in the field. Some are almost while or yellowish, and vary

266

AN ECONOMIC ENTOMOLOGY.

to brown or reddish, sometimes even to blackish, the hair being
of the colors indicated, and the surface of the body hardly visible.
The commonest of all, perhaps, is the Spilosoma virginica, or
"white ermine moth," and this is whitish or yellowish, produc-
ing a snow-white moth, the wings a little black dotted, the sides
of the abdomen and front legs yellow. Another species often
seen crawling about during late fall is Pyrrhardia isabella, and

Fig. 287.

spilosoma vhginica, the wliite ermine moth. — ff, larva; b, pupa ; <", adult.

this caterpillar may be recognized by having the central portions
of the body red-brown, while the anterior and posterior segments
are black. This produces a uniformly brownish-yellow moth.
All the moths fly at night, and are but rarely seen during the
day, and all the caterpillars, where they become troublesome,
are within reach of the arsenites.

An exception to the general feeding habit we find in Hyphan-
tria ciinca, the caterpillar of which is known as the " fall web-
worm." The moth is white, sometimes without spot or mark
of any kind, usually with only a few black dots, but occasionally
with the spots forming more or less evident bands across the
wing. The eggs are laid in masses on trees, and the larvae, as
soon as they hatch, form a little web in which they remain so-
cially, except when feeding. They eat first the leaves within,
then those close to their nest, gradually separating until some-
times an entire tree becomes defoliated from a single point. This

THE INSECT WORLD.

267

species often becomes a serious pest in cities on shade-trees.
There are two broods, the second being usually the one most

Fig. 288.

The fall web-worm, Hyphantria cunea.—a, b, c, varieties of larva ; d, e, pupa ; /, moth of
the normal white form.

noticeable, whence the name "fall" web-worm, to distinguish it
from the common orchard tent-caterpillar, which appears only in

Fig. 289.

Hyphantria cunca: variations in the markings of the wings.

spring. A large variety of trees and shrubs is attacked by this
insect, and where abundant it becomes a great nuisance. Usu-

268

A A' ECONOMIC ENTOMOLOGY.

ally its natural enemies keep it in check, but sometimes it seems
to outrun them, and then for a series of years in succession it
becomes increasingly abundant until, as suddenly as it increased,
it disappears so nearly that nothing will be seen of it for a few
years. If the insect is taken in hand as soon as noticed, cutting
down and destroying the newly formed nests with all the cater-
pillars they contain will pro\e the most satisfactory remedy, or
the foliage just surrounding them may be sprayed with an arsen-
ical mixture.

There are other species in this series, like those belonging to
che genus Halisidota, which sometimes infest shade-trees, but
rarely in numbers sufficient to be troublesome. The caterpillars
may be distinguished by having slender pencils of hair, and some-
times a series of dorsal tufts. The moths are brownish yellow,
with rows of semi-transparent and irregular, light-brown spots
arranged almost in bands. Economically none others of the
Ardians are troublesome, though we ha\'e many species that are
common enough when sought for.

In the family Lymantriidce we have what are known as the
"vaporer, " or "tussock moths." Of these the Notohphus
{Orgyid) leiccostigma, or "white-spotted tussock-moth," is
the most common. It feeds on a great variety of trees in the

larval stage, and is

Fig. 290.

Caterpillar of Notolophus leucosligiiia.

seriously troublesome
in cities and towns.
The caterpillars are
rather pretty creat-
ures, with bright red
heads resembling
sealing-wax in ap-
pearance, and yel-
low bodies bearine a

series of dense, abruptly cut oft" brushes on the middle of the
back, and two pencils of black hair anteriorly. They are rather
more than an inch in length, when full grown crawl down the
trees, and, either on the trunk or somewhere in the vicinity, under
any projecting point on fence-rail or the like, make their dirty-
whitish cocoon of mixed silk and hair. In due time the adults
emerge, the male bearing fully developed wings, while the

THE IXSECT WORLD.

269

female has no trace of tlieni whatever. Tlie wings of the male
are dusty gray in color, crossed by rather distinct, blackish lines,
and with a little white spot near the outer lower angle, which
gives the insect its name, Icucostigma. The antennae are prom-
inently feathered or pectinated, and the forelegs are long, very
prettily tufted, and held when at rest projecting some distance
forward. The insect is not often seen during the day, and usu-
ally rests concealed until nightfall, when it seeks its mate. The
female can be distinguished in the pupal stage by its larger size
and the absence of wing pads. When it crawls out upon the
surface of its cocoon it is a grub-like creature with a very heavy

Fig. 291.

The vaporer moth, Xotoloplitis Irncostigma.—a, wingless female on her egg-mass ; b,
young larva ; c, female, d, male pupa ; e, male moth.

body, rather short legs, small head, and very short antennse.
Neither of the sexes are capable of feeding, and as soon as the
male has found the female, oviposition begins. The eggs are
deposited upon the cocoon from which the female emerged, and
as laid they are covered with a snow-white, frothy mass which
hardens almost immediately into a brittle material that serves as
a protection. The first brood of moths appears about midsum-
mer, and from the eggs then laid the little caterpillars hatch in a
few days ; these in turn become adult in fall, and eggs then laid
remain throughout the winter, the prominent white masses soon
turning gray and dirty, and hardly conspicuous on the trees or
other surroundings to which they are attached. In the more
northern States there is a single brood only. These insects when
troublesome to shade-trees are easily dealt with : if all the egg-
masses are removed and destroyed during the winter, the tree
will remain clean during the ensuing summer, provided caterpillars

270

AN ECONOMIC ENTOMOLOGY.

are prevented from crawling up the trunk from the surrounding
points. A band of " dendrolene" six inches in width and half an
inch thick on a sheet of heavy wrapping-paper will serve as a
complete protection if the tree has been cleared of eggs during the
preceding winter. It is easy to see how this is done ; the female
is absolutely incapable of flight, and no eggs can be laid upon a
tree until a caterpillar has first made its way upon it and has
changed to a female moth. Instead of " dendrolene " a broad
band of fluffy cotton will answer for a time, as the caterpillars
become entangled in and are unable to cross it. This sort of
protection must be carefully watched, however, because other-
wise the wet and dirt will harden and cause its failure to act as a
bar. A trough of oil or an inverted tin cone tightly fixed to the
tree may also serve, as will anything else that prevents the cater-
pillars from crawling upon the tree.

Belonging about here in the series comes the European
"gypsy moth," Oaieria dispar, which, imported into Massa-
chusetts in 1868, has caused enormous damage in that State, and
has cost annually many thousands of dollars to keep it in check.
The caterpillar when full grown is about one and one-half inches
in length, of a creamy white, so thickly sprinkled with black that
it seems dark brown, the ground color appearing in the broken
dorsal and lateral lines. It is furnished with distinct dorsal and
lateral tubercles, blue anteriorly and crimson behind the fifth
segment, from each of which arise tufts of long black and yel-
lowish hair. It changes to a chocolate-brown pupa, held in place
by a few threads forming the merest apology for a cocoon, from
July to September, and a few days thereafter the moths emerge.
The males expand from one and one-half to two inches, are
brownish yellow in color, the secondaries paler with a darker
outer margin, the primaries smoky with darker, irregular, trans-
verse lines. The females are much larger and more heavily
built, the wings often expanding two and one-half inches. They
are creamy white in color, the irregular, transverse lines gray or
blackish. They lay their eggs in masses of from four hundred to
five hundred in all conceivable localities, and cover them with
yellow hair and scales from the end of the abdomen. They are
deposited from July to late in September, and the larvae hatch
early the following year, ranging from April to June, according

THE /A SECT WOK I. P.

271

to temperature and location. The fight against this insect is told
in the reports of the Gypsy Moth Commission of Massachusetts,
and these have been distributed wherever the insect has made its
appearance. It has not as yet extended beyond Massachusetts ;
hence details as to its destruction are not in place here. It is,
perhaps, the most dangerous i)est ever introduced into the
United States, and should the State of Massachusetts abandon its
campaign against it, the annual charge upon the farmers of the
country would become enormous, if not ruinous.

To the family Euclcidcc, or Limacodidcc, belong a series of
rather modest green and brown moths, usually small in size, very

Fig. 296.

The saddle-back caterpillar and its moth, Empyctia slimiilca.

densely clothed with scales and hair, the head much reduced,
and the tongue wanting. This, by the bye, is quite a general
character in the types now under consideration, and which are
termed "spinners," because most of the caterpillars make a
more or less complete cocoon of silk. The Liiiiacodids are rarely
common, and only one species, Empretia stimidca^ has become
troublesome in the caterpillar state. This is a very curious, slug-
like larva, somewhat flattened and oblong in shape, most of the
body green in color, but with a quadrate, red-brown patch
resembling a saddle on the middle of the back, and a brown
patch at each end of the body, from the outer edge of each of
which arises a long, fleshy process, set with stiff" spines in all
directions. Small warts or processes are found along the sides
of the body, set with stiff" hairs in the same way. It has no ap-

272

AN ECONOMIC ENTOMOLOGY.

Fig. 297.

A tubercle from a saddle-back moth, Emf>rrtia slimulea, showing the poisonous spines, very
much enlarged. The short pointed tips break off readily and remain in the wound.

THE IXSECT WORLD.

273

parent legs, but seems to crawl directly upon its belly, as do all
the other caterpillars of this family, most of which have similar,
though less developed, spinous processes. Another peculiarity
which this species shares with others in the family is, that when
handled, it causes a burning pain as if nettles had been touched.
The hollow spines are terminated with easily detachable, very
short, stiff tips, and at their base is a gland which secretes an
urticating liquid. Handling the caterpillars roughly results in
breaking off the little tips, which enter the skin and at the same
time release a little drop of liquid, which, entering the wound,
causes the burning sensation. With some persons this becomes
a serious matter ; first inflammation, then swelling sets in, and in
extreme cases a numbness or partial jjaralysis of the entire limb
ensues. As a rule, however, the irritation is local, and no worse
than would result from handling a nettle. The prompt applica-
tion of ammonia, bicarbonate of soda, or even strong brine
will generally act as an antidote. This saddle-back caterpillar
lives on a great variety of plants, including pear and rose, on
which it is sometimes found in numbers. When full grown it
spins an oval, brown, parchment-like cocoon, and in this remains
unchanged until spring ; then it transforms to a pupa, and from
this issues a brown moth, expanding less than an inch, and
known as Empretia stimulea. A number of other caterpillars of
this family attack fruit-trees, but always in such small numbers
that they can hardly be considered injurious.

The family Psychidce is peculiar in that the larvae are encased
in sac-like structures which they carry about with them, and
from which they derive the common term "bag-worms." The
best known of these, "the" bag-worm, is Thyridoptoyx ephcm-
erceforinis. This is often common in orchards, and also attacks
shade-trees, but is perhaps m.ost injurious on arbor-vitae hedges,
which it sometimes kills. On deciduous trees the insects are
usually noticed during the winter, when there may be found
hanging to the twigs and branches cone-shaped bags of silk
varying from a little less than an inch to an inch and a quarter in
length, and studded with bits of sticks and leaves. If the
smaller of these bags are cut open at this time there will be found
an empty pupa shell, but in the larger there will be found a mass
of yellow, fluffy material embedded in which is a great mass of eggs.

18

274

A/^ ECONOMIC ENTOMOLOGY.

In the spring these eggs hatch, and the httle larvae make their
way out through the mouth of the bag and feed upon the leaves,
at once constructing for themselves a case made of leaf fragments
held together with silken threads. At this time the bags are
carried upright, and the insects feed on the upper surface of the
leaf As the larva grows it enlarges its habitation, which soon
becomes too heavy to be maintained in an upright position, and

Fig. 298.

The bag- worm, Thyridopteryx ephi'meriTfoymis. — a, larva; b, male pupa; c, female;
d, male moth ; c, bag of female cut open to show the mass of eggs ; f, caterpillar with
bag in normal position ; g, young larvae with bags carried upright.

drops ; the insect continues to feed, attaching the bag by means
of silken threads to twigs when not moving about from place to
place. Late in summer the larvae become full grown, and
wander, sometimes leaving the trees altogether and fastening to
fences or other shelter in the vicinity, and it is this habit that
provides for the .spread of the insects. When they have reached
a place that suits them, the bags are firmly fastened, the opening
is closed, and the caterpillars change to pup^e. Shortly after the
male emerges, and this is a black moth with transparent wings,
short, feathered antennae, and an unusually long, tapering body.
It is quite active and seeks the female, which forms only an
imperfect sort of pupa, and even in the adult condition is a non-
descript without trace of wings and almost without antennae.

THE INSECT WORLD.

275

It is, indeed, a helpless, grub-like creature that awaits the visit
of the male without making an attempt to emerge from its sac,
in wliich it remains even after impregnation. The eggs develop,
finally fill up the bag, and then
the female dies, the eggs rest- ^^'^■

ing in the fluffy mass already
described until the spring fol-
lowing.

This species is best treated
by picking off and destroying
the bags during the winter, and
if this is thoroughly done no
caterpillars will appear on the
trees in the spring, unless they
crawl on from other points
where an egg-sac may happen
to be attached. The meas-
ures recommended against the
"white-marked tussock moth"
can be employed here as well,
and trees once cleared can be
kept free without much diffi-
culty. When arbor-vitae is at-
tacked, the picking should be
thoroughly and carefully done, because these hedges suffer very
rapidly, and once defoliated, usually die. In orchards where
spraying is done against the codling-moth, the "bag-worms"
are destroyed incidentally and no special measures need be taken
against them.

Next follows the family of " prominents," so called from the
fact that the moths frequently have a tooth at the inner margin
of the fore wings, and the caterpillars are sometimes a little
humped. They are technically termed NotodontidcE. Most of
then} have a small, retracted head, many of them a short or
obsolete tongue, and some are more or less troublesome on cul-
tivated plants.

One of the best known is the "yellow-necked caterpillar"
often found feeding on apple-trees in colonies of from fifty to
more than one hundred. When full grown it is nearly two inches

The bag-worm.— a, sack of female cut
open to show the grub-like creature at its
mouth ; b, the female removed from the
bag, much enlarged.

276

AN ECONOMIC ENTOMOLOGY.

in length, with a black head, a yellow neck, and the rest of the
body yellow and black spotted. It has a peculiar habit of hold-
ing by the false legs only and dropping the head and anal seg-
ments when at rest. The insects feed very rapidly and often
defoliate large branches before their presence is realized. When
full grown they descend to the ground, burrow a short distance
beneath the surface, forming a conical pupa, and remain in that
condition during the winter. In spring the moths emerge, and
are of a brownish-yellow color, crossed by rather even, narrow.

Fig. 300.

The yellow-necked caterpillar, a; its parent, Datana ministra, at b ; eggs, natural size
and enlarged, at c and (/.

brown lines ; and this species is Datana viinistra. It lays its
white eggs to the number of nearly one hundred on the under
side of apple and other leaves in a single layer. Similar cater-
pillars may be found on a variety of other plants. The sumach
is often defoliated, walnut- and oak-trees have their own species,
and in all cases the moths have the general appearance already
described. Insects that feed thus in company are controlled
without difficulty, if we attack them as soon as the colony has
hatched. They are then confined to a few leaves, and if these
be picked off" and destroyed, injury is avoided for the season. If
this is not possible, or the colony has already spread too great a
distance, then spraying the infested brancli with arsenites will
answer every purpose.

There are other caterpillars of this family that attack fruit-trees,
but as a rule in such small numbers as to be harmless.

Oak-trees are occasionally attacked and defoliated by cater-
pillars about an inch and a quarter in length, with a yellow head,

Fic. 304.

V\G. 295.

Kig. 292. larva oT iJMisy iimlli. Fij;.s. 294, 295, gypsy iiiolli. (I iirria disfiar, male ami
fcinali-. Fig. 304^ Aniiula sciia/uria, larva. Figs. 305, 306. .liiisu/u sciuitoria, iiuilu and
female.

THE IXSECT WORLD.

277

the body striped with narrow black or reddish-brown hnes, ex-
cept at the sides, where it is gray or yellowisli. Near the pos-
terior extremity is a rather prominent, humped segment entirely
red in color. When full grown they go underground, and from
them come, in the spring
following, moths gray in
color, mottled with brown,
but the front of the body
and a margin along the
anterior edge of the fore-
wings white or nearly so.
These are called Edema
albifrons. The body is
rather cylindrical, heavy,
extending somewhat be-
yond the hind wings
and obtusely terminated.

Feeding exposed as these insects do, they are readily destroyed
by the arsenites.

One other caterpillar sometimes occurs in swarms on a great
variety of plants, including some fruit-trees, and this is known
as the "red-humped prominent." It is yellowish brown in
color, pale along the sides and striped with slender black lines.
The fourth segment is humped and of a red color like that of the

Fig. 302.

Ediiiia albi/rinis ami its larva

CEdemasia conciiiua and its larva, the " red-humped prominent."

head. There are a number of short spinous processes along the
back, and some which are larger and more prominent on a hinder
segment. The moth that emerges from this larva is the CEdem-
asia co7icinna, and is of a light-brown color, the wings expand-
ing a little more than an inch, the anterior pair dark brown along
the inner margin and more or less gray tinged before. The

278 AN ECONOMIC ENTOMOLOGY.

measures already recommended are applicable to this species,
and in fact none of the caterpillars belonging to this family need
ever cause serious trouble or difficulty in their control.

Next come the Ceratocampida", containing only a few very
large species whose caterpillars are more or less furnished with
horns, spines, or similar processes. The moths are sometimes
contrastingly colored and distinguished by having the antennae
in the male feathered for only a portion of the distance ; the ter-
minal third of the stalk lacking the pectinations, while towards the
base there are two branches to every joint.

Occasionally we see a very large, green caterpillar, with black
and red blotches, and with four very long horns, yellow at the
base and black at the tip, on the first segments. This is an
insect much dreaded, and known by the attractive name of " the
hickory horned devil." The first part of the name is from the
food plant upon which it is often found, the second from its prom-
inent horns, and the third from its supposed evil inclinations.
Yet the creature is absolutely harmless, incapable of inflicting the
slightest injury upon even the most delicate subject, and it de-
pends for protection entirely upon its formidable appearance.
The moth resulting from it, atheroma rega/is, or " regal wal-
nut-moth," is rare and seldom seen, flying only at night and not
much then, because, having no tongue, it does not feed. It is,
however, rather handsome, tawny brown in color, the veins
streaked with red and with two series of more or less distinct
yellow blotches. It expands from three to nearly six inches, and
is one of the largest of our night-flying moths.

The species belonging to the genus Anisota are sometimes
much more abundant, and occasionally become troublesome on
oaks. I have seen acres of forest almost entirely defoliated by
large yellow and black-striped caterpillars, with black head, two
long, black filaments on the anterior, and numerous shorter
black processes on the other segments. These are the ' ' orange-
striped oak-worms," which, when mature, go beneath the sur-
face of the ground, change to brown, roughened pupae, and in
spring appear as brown moths ; the Anisota senatoria. The males
are much the smaller, have the fore-wings somewhat triangular
and pointed, a little transparent towards the middle, and with
a clear white spot near the centre. The females are rather

THE INSECT WORLD.

279

lighter in color, the white spot is much sinaller, and the wings
arc not in the least transparent, but irrorated witli darker, small
spots, which give them a powdered appearance.

On maples, especially in the more southern States, we often
find a smaller caterpillar, which js green, with black stripes, and
marked with little red dots. The resulting moth is known as
the "rosy Dryocampa," and has the fore-wings rose colored.

Fig. 307.

Dryocampa rubicunda. — a, its larva ; b, its pupa ; r, female moth : the rosy
Dryocampa.

crossed by a broad pale-yellow band, while the hind wings are
pale yellow, with a short rosy band behind the middle. It is
rarely abundant enough to need attention, but when it does, the
external feeding habit indicates the remedy at once.

Next we reach the series of species that are silk-spinners par
excellence in the caterpillar state. They are known in a general
way as bombycids from the term Bonibyx^ which was for a long
time applied to the "silk- worm." Among the largest of our
Lepidoptera are the species of Attacus, which expand from four
to eight inches, and are allied to the giants of the tropical region,
which have a spread of wing of sometimes fully twelve inches.
None of our species are ever numerous enough to be really
troublesome, and they are interesting rather from the habits of
the caterpillars, which, before changing to pupae, spin a very

28o

A.V ECONOMIC ENTOMOLOGY.

large and dense cocoon of silk, in which they remain until ready
to transform into moths. The most common of these spinners

is the cecropia, Platysamia cecropia, the caterpillar occurring on
a great variety of plants, including many of our fruit-trees and

THE INSECT WORLD. 281

certain small fruits. It is green, and has six rather j)roniinent
warts on the thoracic segments, of which four are coral-red in
color and the hinder two are yellow, sometimes with a reddish
tinge. On the rest of the body are other tubercles which are
furnished with little clusters of spurs and spines. The cocoon is
sometimes spun in bushes, attached to a twig, sometimes at an
angle of a fence, or wherever the caterpillar happens to consider
it convenient. The resulting moth is dusky brown and powdery,

Fig. 309.

Caterpillar of the cecropia moth.

tlie hinder margins clay-colored, a kidney-shaped dull-red spot
with a white centre and a narrow black edging is near the
middle of each wing, and beyond the spot is a wavy dull-red
band, bordered internally with white. The primaries near the
base are dull red, and near the tip is an eye-like black spot within
a bluish-white crescent. Several other species occur, all more
or less resembling in general appearance the cecropia, and spin-
ning much the same kind of cocoon.

Of a somewhat different type is the polyphemus, Telea poly-
phennis, which has a green caterpillar without prominent tuber-
cles, but with little, black, wart-like processes, giving rise to
small, stiff bristles. This feeds upon oak and a variety of other
trees, but is rarely abundant, and when forming its cocoon spins
np in a leaf, which later drops to the ground. This cocoon is
o^-al in shape and completely closed, differing from that of
cecropia and its nearest allies, in which it is open at one end.

282

A,V ECONOMIC ENTOMOLOGY.

Fig. 310.

The moth is dull ochre-yellow in color, more or less clouded
with black in the middle of the wings, on each of which there

is a transparent eye-like spot, divided
transversely by a slender line and en-
circled by yellow and black rings.
Before and adjoining this spot in the
hind wings is a large blue patch
shading into black.

With a very similar caterpillar and
cocoon, the luna moth, Adias hma,
is entirely different from the poly-
phemus. It is of an even, bluish-green
color, sometimes verging into yellow-
ish, with a little eye-like spot on all
wings, the anterior border of the fore-
wings margined with scarlet, while the
hind wings are each furnished with a
long tail.

When these caterpillars are noticed
on a cultivated plant they can be
easily picked off and destroyed, but
as a rule their natural enemies serve
to keep them reduced to compara-
tively small numbers. These Ameri-
can species produce a much greater
quantity of silk, of a much stouter
texture than the Chinese silk-worm
proper ; but, unlike it, their thread
cannot be reeled. It is this that makes
it impossible to use our species suc-
cessfully for the production of a cheap
and strong silken fabric.

We sometimes find on corn, clover,
apple, and other plants or trees a
green caterpillar, with a brown stripe edged with white on each
side of the body, covered also with little processes, from which
arise clusters of prickly spines. These have urticating proper-
ties, so that if the larvae are carelessly handled a certain amount of
irritation may arise, though much less than is the case with the

Cocoon of the cecropia moth.

THE IXSECT WORLD.

283

slug-like cateri^illars j)reviously described. They become rather
more than two inches in length, spin a thin, irregular, and some-

what parchment-like cocoon, and emerge in due time as " io"
moths,- — Automcris i^Hyperchirid) io. The male is deep yellow,

284 -^^^^ ECONOMIC ENTOMOLOGY.

the primaries only a little banded with narrow lines, the wings
reddish on the interior margin, with a narrow band of the same

color outwardly. On the
Fig. 312. middle of the hind wing is a

large, round, blue spot, with
a broad black border and
a central white dash. In
the female the primaries are
purple-brown, the transverse
lines gray and much more
prominent, and there is a
somewhat dusky, pale-mar-
gined, nearly kidney-shaped
discal spot. The hind wings
are essentially like those of
the male, and altogether this
sex is larger than its com-
panion.

The only other of the silk-
spinners to which attention
need be called here are the
species of Clisiocainpa, which are interesting from the fact that
most of them live in colonies and spin a tent of silk on the trees

Fig. 313.

Larva of io moth.

Auto»ie) is io, female.

attacked by them, whence they are called "tent-caterpillars."
Our common species in the East is C. aniericana, found in apple

THE IXSECr WORLD.

285

orchards very early in the spring. During the winter we often
find on the small twigs of the apple an incomplete belt of a
\'ery dark brown, wax-
like material. If we ^'^- ^'4-
examine this carefully
we find it to consist of
a very large number of
eggs soldered together,
from which caterpillars
hatch, sometimes be-
fore the leaves have
started, which at once
spin a litvle web or tent
in the nearest fork.
Here they live in com-
pany, moving out from
time to time to feed
upon the surrounding
leaves, and increasing
the size of their habita-
tion as they grow. The
"tents" form promi-
nent and unsightly
objects in neglected
orchards, and are some-
times rather unpleas-
antly conspicuous in
others that purport to
be well kept. When
full-grown the cater-
pillars abandon the
nest, crawl to some
convenient shelter in
the vicinity, and spin a
yellow, rather thin cocoon, which becomes covered with a fine
yellow powder. The moth is dull reddish in color, more or less
brown-tinged, and the fore-wings have two oblique, pale stripes.
'Hie males are considerably smaller than the females, and as a
rule darker in color, tending to have the wing between the lines

The American tent-caterpillars, a and b, on the out-
side of their tent near the entrance ; d, cocoon ; c,
egg-mass of an allied species ; above all the female
moth, Clisiocanipa ainericaiia.

286 AN ECONOMIC ENTOMOLOGY.

paler, while in the female we have, on the whole, an opposite
tendency. In the West, other species replace the americana,
but their habits remain essentially the same, and they may be all
treated in the same manner. During the winter the egg-masses
are easily seen after a little practice, and they can generally be
reached and cut down without trouble. Early in spring the
nests are prominent objects and easily destroyed, with the entire
colony. Where they are out of easy reach, simply spraying the
branches nearest to their nest will destroy them in a day or two.
In orchards in which spraying is systematically done for other
pests, these insects rarely get a foothold.

The true silk-worm, Sericaria mori, though economically im-
portant, is hardly a proper subject for this work. Its history is
so well known, and has so many special books devoted to it,
that it is unnecessary to go into details here.

In the family Cossidce we have a series of very peculiar moths,
really low in the scale of development, but formerly placed about
here in the classification and conveniently so treated. The cater-
pillars are all wood-borers, living from two to four years in the
trunks or roots of trees. They are white, or with a faint red or
yellow tinge, more or less black spotted, and with short, bristly
hairs. The head is large and horny, usually black, and the jaws
are stout and prominent. When full-grown they are from two
to three inches in length, and change to a rather slender, cylin-
drical pupa an inch to an inch and a half in length, depending

upon the species and sex.
Fig. 319. This pupa is furnished with a

series of spines around the
edges of each segment and
sometimes also with a chisel-
Pupa of the goat-moth. ^i^e protuberance on the head-
case. When ready to trans-
form, it works itself by a twisting and wriggling motion through
the bark and for half its length out into the open, holding fast
by the spines on the abdominal segments. The adults, known as
"goat-moths," from a rank odor peculiar to them, have rather
narrow, pointed wings and a long conical abdomen. The
females are heavy fliers, and both sexes are attracted to light,
though rarely seen otherwise. The head is small, very much

THE INSECT WORLD.

287

retracted, and the tongue is obsolete, so that the insect is in-
capable of feeding. None of our American species attack culti-
vated plants or trees so as to become injurious, though in forests

Fig. 320.

Goat-moths, Prionoxystus robiniie, female and male, and their larva.

young oak timber is sometimes badly injured by the Prionoxys-
tus robinicB.

There has been recently introduced into the Eastern United
States a European species known as the leopard-moth, Zeuzera
pyrina, and this has become a pest on the shade-trees in several
of our Eastern cities. The male moths expand a little more than
an inch, the female over two inches, and both are white, spotted
with black, whence the common name " leopard-moth." There
is great difficulty in dealing with insects of this character, owing
to their food habits. Fortunately, even in this imported form,
the natural checks seem to prevent its doing much injury to
orchards or country trees ; but in the cities and towns it threat-
ens the life of the shade-trees. The onlv recommendation to

288

^A' ECO NO All C ENTOMOLOGY.

be made is constant watching by some man especially employed,
who will destroy the borers just as soon as their presence is
noticed, and who will gather the moths beneath the electric lights
now found in most cities. Pans in which oil or some other sub-
stance is kept to kill the insects falling into them, properly
arranged just beneath the lights, will prove of considerable

Fig. 321.

The wood "leopard-moth," Zeiizera pyrina. — a, b, larva, from above and side, about
half grown; c, male, rf, female; e, larval burrow, showing the tendency of the full-
grown caterpillar to girdle its food plant.

benefit ; but it will take years of steady work to lessen the insects
in some of our cities, and to remove them as a source of danger
to the shade-trees.

In the idimWy Noduidcs, or "owlet-moths," we have a large
number of species, and among them many that are troublesome
to the agriculturist. The moths are, as a rule, sombre gray or
brown, expanding when the wings are spread between one and
three inches, averaging perhaps an inch and a half in the majority
of cases. The fore-wings are comparatively narrow, rather short

Fig. 32^v

IMC. 315.

Kij;. 2Qv. pupa of dypsy niolli. Fit;s. 315, 316, 317, larva, cocoon, ami male moth
oi Snicai ia iikhi, llic silk-worm. I''ijj. 31S, motli, and Fig. 323, larva oi Aciunycta
americaita.

THE INSECT WORLD.

289

and stout, crossed b}- a series of more or less marked crenulated
or wavy lines, and with two usually darker or paler spots in the
discal part of the wing. Of these, that nearest to tlie base of
the wing is round or nearly so, and is called the orbicular ; the
other and larger, nearest to the outer part of the wing, is kidney-

FiG. 322.

x^-^'^r^^^^ .. or

Wing of an owlet-moth, with all the markings defined and named. — Right wings:
b, hasal line; t.a., transverse anterior line; m., median line or shade; t.p., transverse
posterior line; si., sub-terminal line; t., terminal line; sm., sub-median vein; apex
of hind wing: o.;«.', outer margin ;?.>«.', inner margin. Left wings : 6. rf., basal dash ;
cL, claviform ; or., orbicular spot ; len., reniform spot ; ap., apical spot ; cm., costal mar-
gin ; o.tn., outer margin; /.;«., inner margin; h.a., hind angle; d.s., discal spot; e.l.,
exterior line ; an., anal angle.

shaped, or narrow-ovate, and is called the reniform. These
terms are frequently used in economic literature, and the spots
are in many cases characteristic. Taken as a whole, the species
of the Noctuid family are very much alike, and no attempt will
be made here to distinguish them, except in the most superficial
manner. The hind wings are usually without markings, and
when at rest are concealed by the fore-wings, which lie overlap-
ping and covering them, either flat on the back or roof-like, a
little oblique. In the early part of the series we have a number
of species with hairy caterpillars that sometimes feed on shade-
trees. We occasionally find a rather large yellow caterpillar,
densely clothed with soft yellowish hairs and interspersed here
and there a pencil of much longer, black hair. This is the cater-
pillar oi Acronyda ainericana, one of the "dagger-moths," so

19

290

AA^ ECO NO AUG ENTOMOLOGY.

called from the fact that on the fore-wings there are a number of
short black streaks crossing the transverse lines in such a way
that the marks have a remote resemblance to a dagger, or to the
Greek letter/^/, i<. They are all of some shade of gray, varying
from very light ashen or nearly white to almost black ; but none
of them are seriously injurious.

The more typical Noctuids are rarely seen during the day.
They hide under bark or stones, in out-houses, or wherever they
can find shelter. Occasionally they sit brazenly upon the trunks
of trees or branches, or openly upon stones, their colors and
markings blending so perfectly with their surroundings that they
are invisible, except to the trained eye ; but at night they are active
and fly readily, many of the species being attracted to light, and
nearly all of them to sweets : for these insects are furnished with a
well-developed tongue and require food. When the moths are
examined in the dark, their eyes are seen to glow with a deep
phosphorescence that is quite startling at first sight. The ento-
mologist makes use of their sweet tooth by what is known as
' ' baiting " or " sugaring, ' ' placing a mixture of molasses, beer,
and rum in patches upon trees, fence-posts, or even stones, and
visiting them after dark with a lantern. The moths are often
attracted in great numbers to these lures, and many species not
otherwise obtainable are thus added to our collections. Many of
their caterpillars are known as "cut- worms," and when full-
grown average from an inch to an inch and a half, sometimes
reaching, but rarely exceeding, two inches in length. They are
naked, obscurely colored, usually varying from dirty gray to
dirty yellow-brown, generally wilh feebly-marked longitudinal
lines, and rarely with well-marked black spots. They hide
during the day a little below the surface of the ground at the
base of the plants upon which they feed, and during the night
come out to feed upon whatever vegetation they can find. Nor-
mally, the female moth lays her eggs in grass land after mid-
summer, but sometimes weedy fields are selected, or partly
overgrown orchards, or, in fact, any location with a sufficient
quantity of low vegetation to support the caterpillars. They are
rarely laid directly on or in the ground, but may be deposited on
trees, stones, or leaves. When the larvae hatch, late in summer
or early in fall, they feed upon whatever vegetation is in the

Fir.. 331.

Cut-worms and owlet-motlis. — Fig. 324, Agrotis ypsilon and its larva, the "greasy
cut-worm." Fig. 325, larva oi Noctua clandestina, the clandestine cut-worm. Fig. 326,
Peridroma saxicia. Fig. 327, eggs of the same, a single example enlarged at a. Fig.
328, its larva, the variegated cut-worm. Fig. 329, Carneades tnessoria and its larva, the
dark-sided cut-worm. Fig. 330, the climbing cut-worm, larva of Carneades scandens.
Fig. 331, Hadena dcvaitalrix and its larva, the glassy cut-worm.

291

292

AN ECONOMIC ENTOMOLOGY.

fields, being by no means nice in their choice, and only requiring
that it be juicy and that there be plenty of it. They become
about half-grown before winter sets in, and hibernate among the
roots of the plants upon which they have been feeding, or under
stones, logs, or other cover. In this condition they remain until
the spring following, and then manifest quite a variety of habits.
In orchards some of the species develop a climbing tendency,
and make their way upon trees or shrubs to cut off the young-
shoots and buds. These have been termed ' ' climbing cut-
worms," but as a matter of fact a number of species develop
this habit when the larvse are in the proper location. Where
there is an abundance of low plants, these are eaten off at about
the surface of the ground, and the cut-worms fill themselves
until they seem almost ready to burst with the juicy tissue.
Where sod land has become badly infested by them, and is
ploughed and planted in spring, very frequently everything is
eaten off as fast as it shows above the surface. In some cases,
where they are very numerous, it is absolutely impossible to
obtain a stand of corn, and the crop must be abandoned in favor
of some other which the insects do not attack, although this
apparent exemption is frequently due to the fact that the insects
have wandered off, or have become full-grown and changed to
pupae. This change usually occurs some time during the latter
part of June, or in July, and little complaint of injury from cut-
worms is heard after that period. The moths do not make their
appearance until late in August or September, and lay their eggs
during the latter month. Some species are double-brooded, and
may be found even later than this, until November or even
December. This, be it understood, is only a very generalized
history of one group, and is not intended to apply even to all of
the genera whose larvae are cut-worms ; but for all practical pur-
poses the injurious species may be assumed to have habits
similar to those just described. The reason cut-worms are so
injurious is that the abundance of plants in an overgrown field
where the eggs are laid is replaced by a very small quantity set
out by the farmer for his purposes. The result is that the cut-
worms, comparatively moderate in number in the first place,
become exceedingly plentiful, and destroy the cultivated plants
about as fast as they make their appearance or are set out. In

THE INSECT WORLD. 293

regions where cut-worms art- known t(j be troublesome it is a
good plan to fall-plough sod-land as early in the season as conven-
ient. This will avoid egg-laying by the late moths, and cater-
pillars that have already hatched will be compelled to make their
way to points where food is more plentiful, leaving the ploughed
field free. It is a good plan also to put on at this time all the
potash that is to be used on the crop in the form of kainit.
The insects do not like this material on account ot the chloride
it contains, and many of them will be killed, while most of the
others will be driven off. The potash is not lost, but will be
as effective as if applied the season following. The field can be
treated in spring as needed by the special crop, and will then be
practically free from cut worms. If this method is not feasible
for any reason, the cut- worms can be trapped by spreading on
the surface of the ground, after it has been prepared, little heaps
of poisoned vegetation, — for instance, clover; but any succulent
plant will answer the purpose as well. The best way is to thor-
oughly spray a patch of clover or other vegetation with one of
the arsenites, one pound to fifty gallons of water, then mow it
close to the ground, and spread in little heaps all over the field.
The cut-worms, finding nothing else to feed upon, will eat this
poisonous bait, and long before the corn or potatoes come up the
field will be entirely cleared. On plants like sweet potatoes,
cabbages, or tomatoes, that are set out, protection can be secured
by putting at the base of each plant a tablespoonful of poisoned
bran, using bran at the rate of fifty pounds to one pound of
Paris green. This should be thoroughly mixed dry, then water,
just a little sweetened with sugar, should be added until the
whole is thoroughly wet but not sloppy. This mixture is ex-
ceedingly attractive to cut-worms, being preferred to plants in
all the instances that have come under my notice. It will take
about ten pounds to an acre of potatoes as ordinarily planted,
and perfect protection can thus be secured. For one or two
nights, perhaps, a few plants may be cut, but after that, except
in rare instances, no further trace of the insects will be no-
ticed. As against the climbing cut-worms a band of gas-tar
or coal-tar will in most cases afTord protection, especially if
reinforced by a little mass of the poisoned bran at the base of
each tree. A broad layer of fluffy cotton batting, tied at the

294

AN ECONOMIC ENTOMOLOGY.

bottom and folded over to form a cone, is a^ good substitute for
the tar.

Further on in the family we have a series of species which,
with similar habits in the adult, have quite different larval char-
acteristics. The moths themselves are different in appearance,
becoming white or yellowish, without obvious markings, except
irregular streak ings on the veins and a series of more or less
marked black dots. These are usually members of the genus
Leucania, and the caterpillars have been called in general " army-
worms," though to only one of the species can this term be prop-
erly applied. The "army-worm," Leucania unipiincta, has the
fore-wings of a rather even, dull-reddish fawn, powdered with
fine black speckles, some of which form a transverse row of dots

on the veins beyond
P'iG. iv'. the middle. There

is also a fine, ob-
1 i q u e, blackish
streak just below
the apex, and at the
end of the median
vein is a small white
dot, which gives
the wing a rather
characteristic ap-
pearance and the
insect its specific name ^lnip^lncta. The moths fly at night, and
are attracted to both light and sugar, forming in some seasons
the most common of all the insects taken by the collector. The
eggs are laid on the leaves or stems of grasses, using that term
in its widest sense, and usually concealed. The moths favor
rank vegetation, and the caterpillars, when they hatch, attack
whatever is nearest at hand. When full-grown they are from
one and a half to two inc'ies in length, striped with yellowish on
a dark-gray ground. The head is yellow, with fine dark lines,
and the insect is easily recognized when it appears in numbers.
In ordinary seasons, though the larvae may be quite abundant,
they are little noticed and do no particular injury ; but sometimes,
by a combination of circumstances, the number of eggs deposited
early becomes very great and the resulting army of larvae so

Moth of army-worm, Leucania unipuncta, at a; tip of ab-
domen of female at b ; c, d, e, structural details.

THE IXSECT WORLD.

295

Fig.

3.^,V

The armv-worm.

lare:e that they make havoc where they hatch. In thi.s stage they
are noticed in wlieat where it is heaviest, and thence the cater-
pillars spread in every direction. They soon become full-grown,
go a short distance underground to change
to mahoganv-brown pupie about three-ft)urths
of an inch in length, and shortly thereafter
the moths appear. They mate at once and
lay another batch of eggs, from which we
have about midsummer a second army much
larger than the first. These soon eat every-
thing on the ground first occupied by them,
and are then forced by hunger to begin those
marches which have given them their com-
mon name, "army-worm." It is an inter-
esting, though to a farmer not a pleasant,
sight to see the march of these insects from
a stripped field to one that is still green and
flourishing, and to note how quickly every-
thing becomes covered and disappears, a sin-
gle day sufficing to clear a large plot of every trace of vegetation.
When full-grown these larvae in turn go underground, and now
there is a divergence in development. Some of the pupie remain
unchanged all winter ; some of them produce moths, and of
these some will go into winter-quarters and hibernate, while
others mate and lay eggs for a late brood of caterpillars, which
becomes only partially grown. The insects may, therefore,
winter in either the larval, pupal, or adult condition, though it is
probable that the pupa stands the best chance of sur\iving. At
all events, this explains how it is that caterpillars of all sizes may
be found at all times, and that during the entire season moths
may be found. In my own experience, there has not been a
week in the collecting year when I have not taken this insect,
while seeking better species. The remedies to be adopted are
almost entirely mechanical. Where the larvae are noticed at the
first start in grain-fields or grass lands, the patches infested by
them should be at once cut down and utterly destroyed by
fire, and with them, of course, the larvae. The work must be
done thoroughly, because otherwise the caterpillars will simply
crawl to adjacent plots, and the labor is wasted. The thorough

2C)6 AN ECONOMIC ENTOMOLOGY.

application of an ar. enical spray in the infested patch and imme-
diately surrounding it is beneficial in some cases, but there is the
practical difficulty that grasses do not hold a water spray easily.
Using soapsuds instead of pure water will overcome this, how-
ever. If the insects become abundant enough to start on a
march, a narrow strip can be ploughed in its line, harrowed and
rolled, and then the roller can be kept going, crushing the insects
as they come upon it. Or a very strong kerosene emulsion may
be sprayed upon the caterpillars as they advance, and upon the
fields that they are leaving. There will be no vegetation that
need be considered, and therefore the mixture need be diluted
five times only, which will be effective even against the nearly
full-grown larvae. It would seem that following one army of
caterpillars we would have next year a still more destructive in-
vasion, but such is not usually the case. Fungus and other dis-
eases appear and decimate their ranks, their enemies increase
rapidly after the first large brood, and the result is that normal
numbers only survive, unless the conditions which favor their
increase one year continue also the next. As the land becomes
more cut up and cultivated, the danger from this insect is
correspondingly lessened, and where a reasonable amount of
promptness is displaycjd on its first appearance no wide-spread
injury need be anticipated. Everything depends upon the
promptness and thoroughness with which early measures are
adopted and carried out, and all delays will prove costly.

A near relative of the true " army-worm" is the insect known
as the "wheat-head army-worm," Leiicania albilinea. This is
a rather brighter larva, also striped with yellow, never becoming
quite as large as its ally, and peculiar in the habit of eating the
grain or seed of wheat, rye, and other grasses. There are two
broods of this insect also during the year, but that which does
the injury makes its appearance in the nearly full-grown larval
condition just when the grain is ready to ripen. At this time,
when sufficiently numerous, their injuries to the crop are severe,
because a single caterpillar may in a few minutes practically de-
stroy the value of an entire head of wheat. The ears become
ragged and the surface of the soil becomes littered like a barn
floor after threshing. The moths from which these insects are
derived expand a little more than an inch, and are of a rather

rilE INSECT WORLD.

297

pale clay-yellow, with a narrow, silver-gray margin to the outer
edge of the fore-wing. There is also a dusky stripe through
its centre, surmounted by a white
streak, which gives the specihc
name a/bilinea, or "white lined."
Practical measures against this in-
sect are difficult. Where the stage
of the grain warrants it in any way,
the best thing is to cut it at once.
This will save further injury, and the
insects will distribute themselves to
localities where their mischief will
not count so heavily. As with the
previous species, increase is depend-
ent upon conditions which we do
not entirely understand, and here
also the parasites ordinarily obtain
control before the year is out.

The wandering habit is somewhat
developed in this species as well,
and frequently they start in grass
lands and emigrate to adjacent
grain-fields when the wheat-heads
are well advanced.

An insect somewhat similar in
appearance in the caterpillar stage is
the "fall army- worm," Laphygma
fnigipcrda. It is smaller, however,
the head dark with a prominent,
white, V-mark, while the lines are
different and the body is covered
with rather well marked black tuber-
cles, giving rise to short, stiff, black
hair. The creature is a general
feeder, and appears in greatest num-
bers late in the season in fields of
dense vegetation of almost any kind
not differ much from the species already described, and, like
them, it goes underground to pupate. There are always two,

The wheat-heaii army-worm. —
a, a, eating out a liead of grain ; b,
eggs under a leaf sheath ; enlarged
at c, d ; the moth, Leiicania albilinea,
surmounting all.

In general habits it does

298 yljV ECONOAIIC ENTOMOLOGY.

and sometimes three or more broods in the course of the year,
and in favorable seasons these become successively more numer-
ous, so that the fall brood proves the most troublesome. These
favorable' seasons, however, do not often occur, particularly in
the Eastern United States, and here climatic influences or other
natural conditions reach the insects during the winter, so that in
the spring following only a normal number survive. Cultivating
land in crops which admit of fall ploughing is best adapted to

Fig. 335.

Fig. 336.

The fall army-worm.— i, its
head ; c, d, its body segments
enlarged.

Laphygttia fnigiperda and
variations.

avoid injury, and a frequent rotation will prevent them from be-
coming numerous enough to be destructive at any time. The
arsenites can be employed, of course, for the protection of crops
that admit of being sprayed. Wheat-fields badly infested in fall
are not necessarily ruined or even much injured, because wheat
will stand cutting down almost to the ground during the latter
part of the season, and will yet come up vigorous and in good
condition the spring following. The moth that produces this
caterpillar is a modest, gray creature, expanding hardly more
than an inch, and the hind wings are pure white and semi-trans-
parent. It is a variable species, and ranges from an almost uni-
form gray to forms in which there is a considerable admixture of
bluish white, the ordinary lines and spots of the owlet-moths
being also well marked.

TIIF. IXSECT ]VORLD.

299

We sometimes find boring- in the stems of wheat, corn, pota-
toes, and a great variety of other plants a yellowish-white cater-
pillar with nither prominent black spots, luniislud with little
soft hairs and with a black head. This is the larva of another
Noctuid moth, the .Ichatodes zcce. It sometimes does consid-
erable, though usually temporary, injury to the infested plants,
and is kept in check, as a rule, by its natural limitations. The
moth which produces this caterpillar is broader winged than the
species previously mentioned, and the primaries are of a deep,
somewhat mottled, red-brown. The outer margin is rusty red,
especially towards the tip of the wing, and none of the other
markings are well defined. The species has not, in my experi-
ence, appeared in numbers large enough to make it necessary to
adopt remedial meas-
ures, and this is fortu-
nate, because from its
method of feeding it is
somewhat beyond our
reach.

Occasionally we note
upon grape-vines a
smooth, greenish cat-
erpillar with broken,
rather inconspicuous,
lateral lines. It attains a
length of from one and
one-half to two inches,
and differs from the
other greenish cater-
pillars of the vine by lacking all trace of either horn or eye-spot
on the last segment. It pupates a little below the surface, and in
due time appears as a moth which is distinctly flattened, has the
fore-wings of a mottled, dull, smoky brown, and the hind wings
of a dull coppery hue. It is the Pyrophila pyrainidoides, and
may be occasionally found during the day hiding in crevices, or
under bark, for which its flattened body adapts it unusually well.
At night it is attracted to light, and occasionally becomes rather
common, though rarely abundant enough to need remedial
measures. When it does occur in numbers it is easily controlled

Pyrophila pyramidoides and its larva.

300

AjV econoafic entomology.

by the application of a stomach poison, the caterpillar succumb-
ing readily to any of those in ordinary use.

There is a series of decidedly depressed or flattened moths with
narrow, long fore-wings, broad hind wings, a somewhat retracted
head clothed with stitf, projecting vestiture, and a neat little tuft
on the anterior part of the thoracic collar. These belong to the
genus Xylina, or its near allies, and they appear late in fall, to
hibernate as adults. In spring they reappear as soon as the
weather becomes in the least warm, and moths of this kind are

Fig. 338.

Xyliiia antc-nnata : a, its larva in peach ; b, adult motli.

often found in maple groves while sugaring is going on. Some-
times sap-pails are found in the morning with the surface of the
liquid completely covered with these insects, which, taken as a
whole, are northern, though some extend south and southwest,
and even to the Pacific coast. One of the most common is the
X. antennata, the caterpillar of which has been described by
Riley as boring into fruits ; but it is a rare species, comparatively,
and no marked injury is ever done.

Now we reach a group of moths in which the caterpillars
usually lack one pair of the false or abdominal legs, and for this
reason are known as " semi-loopers," having somewhat the
methods of motion found in the "span-worm," but not to so
marked an extent. Of this series we have several more or less
troublesome species, and the most important are the "cotton-
worms" belonging to the genera Anomis and Alejja, all of them
feeding upon the leaves. The larvae are similar in appearance,
green, more or less narrowly banded at the sides, and spotted.

THE IXSECT IVOKIJh

301

K- 339-

The " cotton-worm" is the larva of Aletia argillacea, about which
many volumes have been written, and whose life history has
been thoroughly investigated under the direction of the United
States Entomological Commission
and the entomologists of the United
States Dei)artment of Agriculture.
To one especially interested in this
insect these elaborate reports will hr
useful and must be consulted. It
will suffice here to say that the
caterpillars pupate in a loose co-
coon spun on the leaves of the
plants, and from the dark-brown
[)upa comes a dull, tawny or clay-
colored moth, with intlistinct, dark,
wavy, transverse lines, and a rather
prominent leaden-white spot, more
or less margined with t^lack, near
the middle of the fore wings. There
are several broods in the course of
the year, but only the later ones be-
come seriously injurious, the plant
then being sometimes entirely de-
foliated. A curious feature is that
the insects probably do not spend
the winter in our territory, but adults immigrate each year from
more southern regions. The migrating habit is marked in the
later broods maturing on cotton in our country, and the moths
have been often seen in great numbers as far north as Canada.
As the wings are closely scaled, they do not readily show the
wear and tear of long flight, and specimens have been taken
in the for north as fresh and bright as if hatched there. It is
})Ossible that under favorable circumstances the caterpillars may
support themselves on plants other than the cotton, but we
have no positive information of their having done so. Of late
years the insects are much less injurious than in times past,
largely as the result of a diversified agriculture, which has made
it less easy for them to increase in abnormal numbers. Planters
have also learnt that a prompt application of the arsenites when

Cotton-worms, from
above.

side and

302

AN ECONOMIC ENTOMOLOGY.

the larvae first appear is apt to lessen subsequent injury, if it does
not prevent it entirely. The method of application now adopted
is exceedingly simple, consisting of a moderately stout, rather
elastic, pole, to the ends of which are attached sacks of a coarse
ducking material containing Paris green. This pole is carried
by a man on muleback, who rides between the rows, continually
jarring it so that the poison sifts through the sacks upon the

Fig. 340.

Aletia aigillacea at rest and with wings expanded.

plants. It has been found that undiluted Paris green used in
this way does not injure the foliage, while it is absolutely effective
as against the larvae. Sometimes the pole is made long enough
to hold four sacks, so that four rows are dusted at one time. This
is exceedingly simple and practical, and has the advantage of re-
quiring no expensive outfit.

We have belonging to this series of semi-loopers a number of
moths belonging to the genus Plusia, and most of these have
somewhere in the middle of the fore- wing a dash, line, circlet, or
other marking of silver or gold. Sometimes the entire surface is
metallic or golden, and the species, as a whole, are very hand-
some, with the ground color in most cases velvety gray or
brown. Bright colors or contrasting markings are rare. Several
of the larvae attack cultivated plants, but none as frequently as
that of P. brassicce, the cabbage Plusia. The caterpillar is
green, with rather indistinct lateral lines, and is readily sepa-
rated from the butterfly larva of Pieris rapes, because it lacks
one pair of abdominal legs and is not at all velvety in appear-
ance. Its fashion of " humping itself" also separates it from the
other larva, which always rests fully extended. This may be
dealt with as has been already recommended foi the other ' ' cab-

THE INSECT WORf.n.

bage-worm," and as they infest the plants at about tliesame time
in midsummer, one apphcation of Paris green or London purple
will answer for both insects.

?^VT~^^^

The cabbage Plusia, /-". btassiciC.—a, larva ; b, pupa in its thin cocoon ;
c, male adult.

Another series of usually bright-colored, active moths that fly
during the day, sometimes in the hottest sunshine, is the Helio-
thini, which are usually white or yellow in color, and not infre-
quently have a glossy or metallic lustre. Taken altogether, the
species are not common, and are much more abundant both in
specimens and species in the West and Southwest. But we have
one form, abundant throughout the Eastern United States, which
is at once the langest, least conspicuous, and most destructive of
those belonging here, yielding little, in the injury it does, to any
other Noctuid. It is the Heliothis armiger, whose caterpillar is
locally known as the " boll-worm" in the South, where it bores
into cotton-bolls ; the " corn-worm" in the North, from its habit
of eating into ears of corn, and the "tomato-worm" in some of
the Eastern States, from its habit of boring into tomatoes during
the early part of the season. The species is one of the most
difficult to deal with directly, from its habit of feeding concealed
in such a way that in most cases the application of arsenites is
a practical impossibihty. It has been found by experience that

304

AjV economic extomologv.

corn is the favorite food, and they will attack it in preference to
everything else. This preference is utilized by planting corn in
cotton-fields in such a way that the ears are in attractive condi-
tion at the time when the moths would otherwise oviposit in the
bolls. Before the caterpillars come to maturity they can be de-
stroyed by hand in the ears, or the corn can be cut and fed to
stock, together with the caterpillars. This is really the most

Fig. 342.

Heliothis armiger in all stages.— a, b, egg, enlarged ; c, larva ; rf, pupa in its under-
ground cell; e,f, moths.

satisfactory way of dealing with this insect in cotton- fields. By
providing early corn for the early broods of larvae, and destroying
it before they mature, the species can be kept down to harmless
numbers later in the season. The adoption of a more diversified
agriculture will have a tendency to lessen injury to the cotton,
and if systematic fall ploughing of corn-fields be practised, it
will soon become insignificant. There are two or three broods
in the latitude of New Jersey and even more southwardly, while
in its most northern range a single brood only is normal. In
September or early October the caterpillars that mature in corn
go underground and change to pupae, passing the winter in this

Ftr.. ;,4;v

Work of tlie Ihivii u( llrliolhis ai

lint: r I 111 1-1 nn an

I III luliiaiucs.

THE INSECT WORLD.

305

condition. Early in spring, if the ground remains undisturbed,
the moths, which are of a dull clay-yellow, with indistinct mark-
ings on the fore-wings, and expand from one and one-half to two
inches, make their appearance and lay eggs upon such plants as
they can find. Early tomatoes are favorites, and, following them,
peas are infested. The caterpillars bore at first into the stems
of the tomatoes, but always attack the fruit as soon as it has set.
The earliest tomatoes are thus frequently ruined, and as these
usually have the greatest market \'alue, the actual money injury
is out of all i)roportion to the quantity of fruit destroyed. Sweet
corn is next attacked, and the earlier it is the more abundant will
the insects be found in it. Last of all field corn is taken, and
this remains infested until it becomes hard and glazed, the cater-
pillars being able to make their way through and feed upon the
perfectly ripe kernel. Fortunately, they are great cannibals, and
where several infest a single ear of corn they fight until one alone
remains. On tomatoes the insects cannot be satisfactorily treated,
except by picking and destroying the infested fruit as soon as it
is noticed, and the only practical means of keeping them in
check is fall ploughing all corn-fields. It has been found by ex-
periment and by practical experience that ploughing in the fall
and breaking up the earthen cells in which the pupae rest will in
almost every instance result in their death, and this process alone
offers a fair opportunity for controlling the pest.

There follow in the natural series a great number of small spe-
cies, some of them very bright and pretty, many with interesting
life histories, but none of practical importance from the economic
stand-point. They are in turn followed by a series of larger
species with broad wings and dull colors, the secondaries fre-
quently crossed with lines much as in the primaries. The cater-
pillars are half-loopers in most cases, and bear a very strong
resemblance to the "span-worms." The most common of the
species belonging here are the clover moths, Drasteria erechtea
and D. crassmscula, which are so nearly alike that they have
been confused in collections, and we need not trouble to separate
them. Both are broad-winged, dirty gray or brown in color,
with two more or less marked blackish or brown bands on the
fore-wangs, and a series of little black dots before the apex. The
female is much more modest in color than the male, and the

20

3o6

AN ECONOMIC ENTOMOLOGY.

black markings are so reduced as to be scarcely visible, except
on careful inspection. The caterpillar, which is green and nar-
rowly striped, feeds on clovers, and, while abundant, is not prac-
tically harmful.

Among the pets of the lepidopterist are the species of Catocala,
a series of large moths with the hind wings black, or yellow and

red banded with
f*"'^- -W- black. We have a

great number of
species, and while
the hind wings are
so prominently col-
ored and marked,
the fore-wings are
mottled gray,
brown, and black.
They rest exposed
during the day up-
on the bark of trees,
entirely invisible
because so closely
resembling their surroundings, the gaudy hind wings being com-
pletely covered by the modest fore-wings. While some of the
caterpillars feed upon cultivated plants, especially the plum, they
are never abundant enough to attract attention.

Last in the Noctuids we have the "snout-moths," or deltoids,
the latter term applied from the fact that when the insects are at
rest the outline bears somewhat a re-
semblance to the Greek letter delta J.
The species are recognizable without
much trouble by the unusually long
palpi, which in many cases point directly
forward and form a decided snout. The
only species that has occurred in num-
bers justifying the term injurious is the
Hypena huimili, the caterpillar of which
— a slender green creature — feeds upon
hops. Within my experience it has never been sufficiently
troublesome to make insecticides necessary ; but should it ever

Catocala uUronia and its larva.

Fig. 348.

Hypena hiimiili, hop-vine
moth.

THE INSECT WORLD.

307

become so, there would be no trouMe in protectir.g the plants
by means of the arsenites.

Now we reach the family Gcovictrida, in which the larvae lack
all save one or at most two pair of false or abdominal legs. In
moving they first extend the body to its full length, then bring
the posterior end close to the front legs, looping the body in
the centre, then stretch out again and repeat the procedure,
whereby they have gained the names ' ' span-worms, " " loopers, ' '
or "measuring-worms," and, indirectly, the scientific term
GeometridiE. There is never any difiiculty in recognizing the
caterpillars, and the moths are easily known in most instances by
their slender bodies, small heads, and very broad wings, which
are also, as a rule, frail and thin. The hind wings are here orna-
mented much as are the fore-wings, so that the lines of the one
pair are often continued across the other. When at rest, the in-
sects kecj) the wings extended and flat, much as specimens are
pinned in the cabinet. We have a large number of species, but
comparatively few of them become troublesome.

Perhaps the best known of all are the " canker-worms," larvae
of the species of Anisop-

tayx and Paleacrita. ^^^- 349-

These attack a consider-
able variety of trees, and
are especially fond of
apple and pear, which
are sometimes completely
defoliated. They are
much more troublesome
in the New England and
Northern States, and I
have often seen, in Mas-
sachusetts, orchards com-
pletely defoliated by
them. In New Jersey
and southward they
rarely become trouble-
some. Here, as in some

of the Bombycids, the sexes are unlike, the males being wnnged,
while the females are wingless. The caterpillars, when full-

FiG. 350.

Fig. 349, Paleacrita veinata. — a, male ; b, fe-
male; c, d, structural details. Fig. 3,so, Anisop-
teiyx- pometaria. — a, male ; b, female ; c, d, e,
structural details.

3o8

y4A' ECONOMIC ENTOMOLOGY.

grown, descend to the ground to pupate ; when the females
emerge they crawl up the trunks of the trees, where they are
fertilized by the males, and then continue their journey to the
leaves, upon which they lay their eggs. This habit gives us
control of the insects, for if we simply band the tree in such away
as to prevent either the female or the young caterpillars from as-
cending to the branches, it will be protected completely. Unless
the female can get upon the leaves, the eggs are laid upon the

Fig. .-^51.

Fig. 352.

Canker-worm, larva of Anisoptcryx povietatia.
— (7, *, egg, enlarged ; e, patch of eggs ; r , rf, body
segments of _/, larva ; g, pupa of female.

a, lar\-a of Paleacrita vernata ;
f>, an egg, much enlarged ; c, d,
body segments of lar\'a.

trunk below any obstruction that it cannot pass. The young
larvse will attempt to get to the leaves, and will, if they find an
impassable barrier, starve to death. The best materials, all
things considered, are " raupenleim," or " dendrolene," prefer-
ably the latter, as it remains viscid for the full period during
which the insects hatch, and forms a perfect barrier beneath or
through which no creature can crawl and live. A band six
inches in width and a quarter of an inch or more in thickness
over thick wrapping-paper will prove a perfect protection. Fluffy-
wool or cotton may also be employed, and the former is the most
lasting, but less certain than the "dendrolene."

A near relative of these canker-worms is the ' ' lime-tree moth,
Hybeniia tiliaria, which also attacks a variety of trees, and has
at times been decidedly troublesome. The application of the
arsenites will prove a complete protection in this case ; indeed, we
may say of all the caterpillars belonging to this family, including
the " canker-worms," that they can be controlled by the thor-
ough application of stomach poisons to the plants upon which
they feed.

rilE INSECT WORLD.

309

One curious feature is that nearly all these span-worms closely
resemble little tlried twigs, branches, or even the stems of the
leaves ujion which they feed. Many of them when at rest hold
to the twig by the hind feet only and keep the body rigidly ex-
tended, seeming for all the world like a small process from the

The lime-tree moth, Hybernia liliaria. — Larva all sizes ; winged male and wingless

female.

plant itself. I well remember one occasion when Cymatophora
pampiyiaria was excessively abundant on certain cranberry bogs
on Cape Cod. I saw the spaces that had been defoliated and saw
the edge of the spaces unaffected, but, look as I would, I could
not at first see the caterpillars. It was not until a little smoke
was started over the edge of the attacked portion that larvae were
observed, and then it seemed as if all the little twigs and branches
obtained life in an instant and started travelling:. The insects so

3IO AN ECONOMIC ENTOMOLOGY.

closely resembled the cranberry stems and twigs that even to an
entomologist they were at first invisible.

The balance of the Lepidoptera are classed in a general way as
" micro,'-' or small, although as a matter of fact many of them
are larger than some of the " macros." Yet, as a rule, the fam-
ilies contain small, and sometimes very small, forms.

At the head of this aggregation is placed the superfamily
Pyralididce, which contains species of moderate size, varying
greatly in appearance. We have one series, the Pyraustidcs,
with slender bodies and rather thinly scaled wings. The pri-
maries are banded, the secondaries are moderate in size, never
larger than the fore-wings, and the colors are, as a rule, pale,
usually a light clay-yellow, while the markings, which are wavy,
are yellowish brown or black. The caterpillars in this series are
nearly always green, with pale stripes and spots ; sometimes
without any markings at all. The head is either black or yellow,
hard and shining, and there is a hard shield of the same color as
the head on the first thoracic segment. Most of them have the
abdominal legs crowned with a complete circlet of spines, and by
this character, which is an easy one to see, we can tell with al-
most absolute certainty the caterpillar of a micro from that of
a macro, in which the circlet of hooks is never complete, if we
except the HepialidcE and CossidcB, which will not confuse us, on
account of their great size and wood-boring habits. The pro-
legs are complete, — that is to say, there are four pairs, — and the

Fig. 354.

The pickle-molli, Margaronia nitida/is, and its larva; the latter shown on a small
cucumber which had been eaten into at b.

insects have, therefore, no appearance of or relation to the
loopers, or Geometrid(£. Many, perhaps most, of the caterpillars
are silk- spinners, and often live more or less concealed in folded
leaves held together by a few threads, or in tubes above or under

THE INSECT WORLD.

3"

ground. Occasionally quite large nests are built, and the cater-
pillars are more or less gregarious, or live together in colonies.
One of the injurious species is Margaronia nilidalis, quite a
pretty brown-and yellow insect called the "pickle-moth," be-
cause the caterpillar has the habit of feeding on the cucumber,
boring into and destroying it when about half-grown. It is more
common in the Western States, and no satisfactory recommenda-
tions for its control have yet been made.

The great majority of the caterpillars live upon low herbage
generally, rarely in numbers sufficient to cause perceptible injury,
and most of the species are classified under the genus Pyrausla.
We frequently notice, in jjassing through patches of ferns, that the
leaves, before they become entirely unfolded, are spun up and
held undeveloped. If we look closely we find a typical Pyralid
caterpillar, which is easily observed and bred, pupating in the
web itself, while the resulting moth is typical of this genus.

The most troublesome species is the "garden web- worm,"
Loxostege simiialis, or, as it used to be called, Eurycreon ran-
talis, and this is a great pest on vegetables of all kinds, seeming
indifferent to the character of its food and spinning its small web
e\erywhere on the plants.
It extends over most of
the United States, and
has been more or less
injurious in almost every
section ; but, like many
others, it seems to be
troublesome a year or
two and then escapes
notice for several years
thereafter. So far we
have not been able to
make out a regular peri-
odicity, and the remedy is Paris green or one of the other arse-
nites where it can be practically applied. The insecticide is
sometimes a little slow to act because the insects are more or
less sheltered, and it is only when they feed outside their web
that they risk being poisoned. In some cases the kerosene emul-
sion is useful, and acts more promptly because of its ability

Fig.

355-

The "garden web-worm," Loxostege shnilalis;
— a, larva; b, c, single segments of same; d,
pupa; e, its tip ; y", moth. '

312

AN ECONOMIC ENTOMOLOGY.

to penetrate the webs and come into direct contact with the
larvae.

Sometimes insects of this series are not confined to green
vegetation, as in the case of the "clover-hay worm," Asopia
costalis, which attacks the dry or partially dry product, webbing

it up and causing more or
Fig. 356. less injury. Its near ally,

Pyralis farinalis, may be
found in barns or bins
where grain is carelessly
stored, and the caterpil-
lars make little tubes,
formed partially of silk,
partially of fragments of
the grain and even of en-
tire kernels, upon which
they feed. Rarely, how-
ever, are they abundant
enough to do serious in-
jury, and as against both
cleanliness will go far,
while bisulphide of carbon
will readily destroy the larvae. As against the "clover-hay
worm," nothing is better than to feed up clean from year to year.
Never put new hay upon old, and if stacked outside, lay upon
rails so as to get ventilation underneath. Salting the first two or
three feet has also been recommended, and will probably be
effective.

In the Phycitince there are many sombre-colored little moths,
usually of some gray tint, with rather narrow fore and broad
hind wings. The insects rest with the wings closely folded
around the body, the head a little elevated, and the palpi project-
ing forward, giving them rather an impertinent appearance. The
caterpillars are largely internal feeders, attacking fruits in many
cases, sometimes living in the stems of plants, sometimes spin-
ning up among leaves, in rare cases feeding openly. Occasion-
ally they make a case or sac which they carry about with them,
and in which they are more or less protected.

We have several more or less troublesome species that are

The clover-hay worm, i and 2; its cocoon at 3;
the pupa at 4 ; the moths, Asopia costalis, at 5 and
6 ; at 7 the tubes made by the larvae.

THE INSECT WORLD.

313

rather difficult to deal with. One of these is the Mincola vaccinii,
or "cranberry-fruit worm," which lives in the berry itself, feed-
ing in the seed-capsule, causing the fruit to redden up prema-
turely, and then to dry and shrivel on the vine. A single
caterpillar may eat into every berry upon a fruit stem in the
course of its existence, then

descends to the ground, and
among the leaves and rub-
bish spins a tough little co-
coon in which the pupa
winters safely, even if cov-
ered by water. The eggs
are laid about the middle of
July, singly, on the berries
where the blossoms have
dropped off, under one of
the little triangular flaps.
Once the larvae are in the

Fig. 357-

\;^

Cranberr>-fruit worm, Mineola vaccinii. —

a, cranberry on which (b, c) the eggs are laid ;

, . . r ^< '^rva ; e,/, pupa and its tip ; g, cocoon ; It,

berries there is no way of moth,
getting at them, and, practi-
cally, the only method of reducing their numbers is to pick the
berries as early as may be, being careful to get in all that are
infested. By sorting promptly these can be destroyed before
the larvae leave them, lessening greatly the number of moths for
the following year. The insect is much more troublesome in
New England than in New Jersey or in the northwestern marshes.

Nearly allied, but with totally different habits, is the Mineola
indighiel/a, or "rascal apple-leaf crumpler," so called from its
habit of making irregular, crumpled cases on the apple leaves
upon which the insect feeds. It is rather easily reached, where it
becomes troublesome, by the arsenical sprays, and in orchards
where spraying is generally practised it is incidentally destroyed.
Many other of these little species are found on our cultivated
crops, but, as a rule, in such small numbers as to be hardly no-
ticeable, and only occasionally a species becomes locally injurious.

One of the largest of our Eastern species is the Melitara pro-
denialis, which feeds inside the leaves of the prickly pear or
common cactus of the sandy regions south of Long Island, while
its near ally, M. dentata, is found in an allied cactus in Kansas

314

AN ECONOMIC ENTOMOLOGY.
Fig. -^60.

Fig. 361.

Fig. 360, the Mediterranean flour-motli, Ephestia kuktiiella. — a, larva; i^, pupa; c,/, ailult
with wings spread and at rest ; ff, wing of a variety ; d, e, h, i, structural details. Fig. 35S,
Melitaru prodenialis. — o, larva ; b, c, d, details of same ; e, cocoon ; /, pupa ; g, moth. Fig.
361, the bee-moth, Galleria melonella. — a, larva ; b, cocoon ; c, pupa ; d, e, moths.

THE INSECT WORLD.

315

and the Western plains generally. This caterpillar, at first sight,
resembles one of tlie Noctuids very closely, and is of a beautiful,
cjuite unusual, bluish tint. The moth expands nearly two inches,
and is, perhaps, the largest of those belonging here. It has the
peculiar habit of laying its eggs one upon the other in a pile
which mimics the spines on the cactus leaves ; so, unless carefully
sought for, they are easily overlooked. We find also in this
group of variable habits a species that is carnivorous, Lcetilia

^'•t;. 359-

An egg-stack o( Melilara prudeuialis. — Single eggs shown al a.

coccidivora, which, as its name indicates, feeds upon scale insects.
Unfortunately, it is altogether too rare to be of any practical use,
and is simply a curiosity, the carnivorous tendency in the Lepi-
doptera being extremely rare.

Ephestia kuhniella is another troublesome species, commonly
known a:3 the "Mediterranean flour-moth." It is sometimes
abundant in barns and mills, and, especially in the latter, may do
much injury. Great complaint has been made during the few
years last past, the insects seeming to become more abundant
and to cover an increasing portion of our territory. Cleanliness,
of course, is primarily to be enforced ; but where they are
abundant enough to make it important, the insects can be cleared
out by using bisulphide of carbon. All the rooms should be
tightly closed overnight, and enough bisulphide evaporated to
fiU every nook and cranny with the poisonous fumes. In a
badly infested establishment a second application may be neces-
sary in some cases, but in most instances one has proved effectual.

3i6

A A' ECONOMIC ENTOMOLOGY.

A very curious species is the Galleria melonella, or "bee-
moth," which infests beehives and feeds upon wax. A brood
of these caterpillars sometimes invade a hive and bore into the
wax out of sight of the bees, frequently demoralizing them to
such an extent that they abandon their home, seeming unable to
find a way of dealing with this kind of enemy. In the recent
types of hives there is little opportunity for these pests to estab-
lish themselves, and if the bee-keeper is on the alert, he will at
once perceive any such invasion. It is easy then, by transferring
and cleaning out the infested frames, to save the swarm. The
moths are rather curious creatures, mottled and streaked on the
fore-wings, the outer margins of which are also a little excavated.

Under the general term Crambids we may describe a series of
species with slender body, narrow, rather squarely cut off fore-
wings, and broad hind wings. When at rest the wings are rolled

* Fig. 362.

Crambus V7ilvivagellus. — a, larva ; b, over-, and c, underground tube and cocoon ; rf, e,
/, moths with wings spread and at rest ; g, an egg much enlarged.

up or folded closely, giving the insect a little the appearance of a
tiny cylinder. The head is small, not at all retracted, and usually
furnished with very long palpi that project straight out like a
snout ; as a whole, resembling somewhat one of the groups of the
deltoid Noctuids. The fore-wings are generally white or yellow-
ish, quite frequently streaked or spotted with silver and gold ;

THE INSECT WORLD. 317

but, of course, as in other grouj^s, we have modest species in
wliich gray predominates, and where the longitudinal markings
are rather in the form of black lines or streaks. The majority of
the species belong to the old genus Crambus, and a number of
them are injurious in grass lands, where the caterpillars are
known as " root web-worms." As in many other cases, it is not
so much the grass that is injured as the corn crop which follows
it, and, therefore, we usually find them injurious in proportion
to the length of time that a field has been in grass before being
ploughed for corn. Usually the moths appear quite early in spring,
and the eggs are laid in grass some time in May, loosely attached
to blade or stem, or sometimes simply dropped on the ground.
The larvae, when they begin feeding, make a loose web or tube
of silk, sometimes on the surface, sometimes a little below it.
Occasionally they feed upon the roots, sometimes on the stalk,
and often they enter antl bore into the plant itself. If an infested
grass-plot is ploughed after eggs have been laid or after the cater-
pillars have hatched, such of them as survive attack the corn, if
that is the crop planted. Occasionally entire fields are destroyed,
while quite frequently much damage is done. The moths make
their second appearance a little after midsummer, and are never
troublesome then, because the eggs are laid in grass lands, where
the caterpillars, though abundant, are not noticed. From this
general life history it will be seen that fields can be kept clear by
fall ploughing, or by turning the sod very early in spring before the
moths have made their appearance or had an opportunity to de-
posit eggs. Bare ground will not become infested, nor, usually,
will a corn-field if there is any grass in the vicinity. Where
injury is caused on lands ploughed late, I have found that certain
commercial fertilizers exercise a beneficial effect ; in fields fertil-
ized with potash in the form of kainit or muriate, the exemption
may be complete, while in adjacent plots fertilized with barn-
yard manure, injury may be serious. It is also possible to pre-
vent trouble by planting some other crop between sod and corn,
where such rotation can be profitably adopted.

In the genera Diatma and Chilo we have insects resembling
those already described, but rather larger, v/ith often more slen-
der pointed wings and longer palpi and abdomen. Here the
larvae are usually borers, some in corn, some in sugar-cane, and

3i8

AN ECONOMIC ENTOMOLOGY.

Fig. 366.

some in other plants. As with all other borers, there is difficulty
in reaching them directly, and besides destroying infested plants,
nothing really satisfactory has been proposed. Diatrcea saccha-
ralis bores into sugar-cane and into corn, often doing much in-
jury to the latter crop in the States south of the Potomac.
There are two or more broods, depending on latitude, the last
remaining through the winter in the larval stage in the corn-
stalks. We have thus an obvious remedy in removing and
destroying or using these up completely before the spring follow-
ing. In sugar-cane the matter is not so simple ; but by burning
tops, cutting close to the surface, and planting in fall from sound
canes only, the injury can be at least much reduced if not en-
tirely avoided. It is another in-
stance where an intelligent farm
practice will answer every pur-
pose, without a resort to insecti-
cides of any kind. Mats, both
flat and round, are especially to be
avoided for affected canes.

An interesting little family is
the Pterophoridce, peculiar in
having the wings split into feath-
ers or plumes. Occasionally the
primaries have only a cleft that
does not extend beyond the mid-
dle, but sometimes they are split
for the full length. The hind
wings may be divided into from
four to six feathers, the insects
being therefore termed "plume
moths, " or " feather-wing moths. ' '
As a whole, few of the species are
common, and I am acquainted
with only one that is in any way
injurious, — the "grape plume,"
The caterpillar of this is pale yel-
lowish or nearly white, with little tubercles, from which rise tufts
of pale hair similar to those of some Arctiids, or " woolly bears."
It lives in the tips of young shoots of grape, webbing up the

The grape plume, Oxyptilus peris-
celidactylus. — a, larvae in a spun-up
tip; d, pupa; c, its breast projection ;
rf, moth ; <?, a single segment of larva.

Oxyptihis periscelidadylus.

THE IXSECT WORLD.

319

terminal leaves soon after growth has started, and eating out the
heart. It would seem thus as if considerable injury might be
caused, but really this is not so, because in most cases they do
not attack the shoots until the buds have become freed, — that
is to say, the shoots are attacked above the flower cluster, so
that no injury is done to the resulting crop. When the insects
disappear, which they do quite early, the shoot simply sends out
a new spur from the last leaf, and the effect of their presence is
scarcely noticed. Practically, there is no method of checking
their increase, except by picking off the infested tips or crushing
the caterpillars within the webbed leaves.

We have another scries of families grouped under the Tortri-
cids, sometimes called "bell-moths," from their peculiar appear-
ance when at rest, but more commonly " leaf- rollers," from the
quite usual larval habit of folding or rolling up the edges of
leaves. We have a number of troublesome insects in this series,
and some of them are not easy to deal with. The moths are
quite easily recognized by their broad, short fore wings, forming a

Fig. 367.

Tcras minnta. — a, larva ; b, pupa ;
moth ; (f, case made on apple-leaf.

Fig. 368.

Rhopobota vaccuiiaiia.

more or less obvious shoulder on the front margin. These wings
are held roof-like, the edges overlapping only a little at the
middle of the back, and completely conceal the moderate or
small hind wings. Their colors are frequently bright and con-
trasting, while in other cases they are uniform and sombre, the
entire insect inconspicuous and unattractive. One of the com-
mon species is Teras minida^ whose larva attacks, among others,

320

AN ECONOMIC ENTOMOL OGY.

apples and cranberries : in apples simply feeding upon the leaves
in a little case, but on cranberries often becoming seriously injuri-
ous by spinning up and eating the tips of the growing shoots. It
also feeds on huckleberry and allied plants, and from them goes
to cultivated cranberry bogs. It is there known as the "fire-
worm," and it is distinguished from Rhopobota vacciniana,
another caterpillar with the same habits, by having a yellow in-
stead of a black head. Both these insects have similar larval
habits, but the Rhopobota has only two broods, and hibernates m
the ^^g stage, while the Teras has three, and hibernates as an
adult. There is a curious alternation of generations in this in-
sect, the summer broods being yellow or orange, while the moths
that hatch in the fall and hibernate are uniformly slate-gray.
Cultivated cranberry bogs are covered with water during the
winter, and the moths cannot hibernate on them ; so, as they lay
their eggs quite early in spring, if the bogs are kept covered
until all other vegetation has started, they oviposit elsewhere,
leaving the bogs free. Therefore, holding the water late, say
until at least the middle of May, is usually a fairly complete pro-
tection. The Rhopobota lays
Fig. 369. j(.g eggs upon the cranberry

plants late in summer. They
remain unaffected by the
water with which the bog is
covered until spring, then
hatch, and the larvae spin up
the tips precisely as in the case
of the Teras, the moths com-
ing to maturity early in July.
Eggs for a second brood are
then laid, and these are some-
times sufficient in number to
sweep entire bogs, giving them the appearance of having been
burned over, wherefore this insect has also been called "fire-
worm." As against this species, late holding the water is not so
effectual, because it must be kept on until sufficiently warm to
induce the eggs to hatch, the young larvae dying as soon as they
break the egg-shell, or stifling before they are really born. The
method is feasible on a flat bog where water can be drawn down

Cranberry leaf with eggs of Rhopobota, and
a spray spun up at tip by the larva.

rilE IXSECT WORLD.

321

SO as to warm up rapidly, but there is danger in holding too long,
because if the plants start under water, as they sometimes do, the
crop is ruined. Occasionally, however, it pays to lose a crop
in whole or in part, to free the bogs completely of this insect, as
they will then remain practically safe for several years in succes-
sion. Where water is abundant and the bogs can be readily
reflowed, the practice of the present day is to draw the water
early to induce an early hatching of the insects, and as soon as
the larv?e generally appear, reflow, leaving on the water at
least twenty-four hours. This will not hurt the plants at that
period of their growth, and will kill every caterpillar upon the
bog. The effect depends largely upon the care with which it has
been done and upon the judgment exercised as to the proper
time. It should be de-
layed until the great ma- Fig. 370.
jority of the eggs have
hatched, but should not
be delayed so as to run the
risk of injuring the plants.
In the genus Caccecia
we have several injurious
species, and none more an-
noying than C. rosaceana. „ , . ,, ^ .

-'_ '^ Rose leaf-roller, Caccecia rosaceana. — Larva,

This attacks a great va- pupa, and adult.

riety of plants, but it is

most troublesome on roses, spinning and folding leaves and buds
and so destroying the flowers. These larvae are not easily dealt
with, but spraying the plants with pyrethrum or kerosene emul-
sion as soon as the first signs of injury are observed will generally
serve to keep them down. On a small scale they may be con-
trolled by compressing the spun-up leaves and killing the cater-
pillar in its home.

Some of the species live in communities, making a nest or
web, and such is the Caccecia fervidana, the caterpillar of which
lives on oak, and spins up the shoots of young trees or the tips
of the branches of older ones. In some cases the nests become
from three to six inches in diameter, and when the caterpillars
have reached their full growth they pupate within it, wriggling
out through the silken covering when ready to emerge as moths,

AN ECONOMIC ENTOMOLOGY.

and leaving the empty pupa cases projecting all around. Some
species are occasionally so numerous that the nests constructed
by them become enormous, — four or five feet in height, and
covering young trees entirely. This and other species having
the same habit can be dealt with by early spraying, or, when
feasible, by picking off the webbed leaves or shoots.

The best known of all belonging to this family is the ' ' codling
moth," Carpocapsa pomonella, and there is no insect, except possi-
bly the ' ' plum curculio, ' ' that has done more injury to our orchard-
ists. The moth appears at about the time the apple-trees are in

blossom, and lays a single
■^^ ■ egg upon the young fruit at

the point where the blossom
has dropped off. In a few
days the caterpillar hatches,
eats a little on the outside
for a day or two, and then
makes its way into the fruit
itself, feeding around the
seed-capsule or core, and
making the well-known
"worm" in the apple. Oc-
casionally two or more
moths may oviposit on the
same fruit, and this ac-
counts for the two or more
larvae sometimes found in
one apple. Except in the
northern part of the country,
there are two broods, the
first caterpillars becoming full-grown and leaving the apples about
midsummer, changing very soon thereafter to moths, which lay
the eggs for the larvae found in the ripe apples. The second
brood does not so usually oviposit at the blossom end, but seems
to have a preference for the point where two fruits touch, for we
often notice that in a little bunch of apples every one is infested,
the entrance in all cases being just at the point of contact. In any
event, whether there is one brood or two, the caterpillars of the
last, when full-grown, leave the apples, find a hiding-place under

The codling moth, Carpocapsa pomonella. — a,
apple cut to show borings of the l.irva ; b, place
where the egg was laid and the larva started ;
rf, pupa ; e, larva ; f, g, moths at rest and with
wings spread ; h, head of larva ; ?', cocoon.

7 HE INSECT WORLD.

323

a scale of bark or in a little depression, and there spin a cocoon,
in which they remain unchanged during the winter. The change
to the pupa takes place very early in spring, and the moths appear
as already stated. It has been found that we are able to protect
our trees by spraying them with one of the arsenites as soon as
the blossoms have all dropped and the fruit is well set. At that
time the young apj^lcs are upright, affording a favorable oppor-
tunity for lodging the poison in the caly.x cup, and here it remains
until the larva makes its first and, if the spraying is properly done,
its last meal. Under favorable circumstances a single spraying is
sufficient to prevent injury, but practically two sprayings are re-
quired at intervals of about a week, and a third if rain interferes
to shorten this period, — that is to say, one just as soon as the
blossoms are all off, and the second about a week or, if the
weather remains dry, at most, ten days thereafter. This is to
allow for the irregular hatching of the larvae, the rapid growth of
the young fruit, and to make certain that all may be reached. It
is here that promptness and thoroughness will tell. To be ef-
fective the spraying inicst be done before the larvae hatch, and
the mixture 7)11181 be on every fruit to be protected. In dry
weather ten days between sprayings is not too much ; in wet or
showery weather three days may be too long. The young larva
feeds externally for a day or two only, and unless it is then killed,
is beyond our reach. Success is the result of keeping an un-
broken film of poison on the flower end of each fruit until all
eggs are hatched. One pound of Paris green or London purple
in one hundred and fifty gallons of water is a good strength, or
fifteen ounces of arsenate of lead in one hundred gallons. Some
growers, however, use a mixture of double this strength and find
it advantageous ; they spray carefully, use just enough to cover,
and risk a little burning of the foliage.

The last series in the order is the Tmema, or the " Tineid
moths," comprising the smallest of the Lepidopterous insects.
There is an enormous number of species, and we know very
little about the great majority of them. With few exceptions, the
insects have long, narrow wings, the primaries pointed, the sec-
ondaries lanceolate, but their surface increased by enormously
long fringes, which are in many cases broader than the wings
themselves, They often have on the head a clothing of upright

324

AN ECONOMIC ENTOMOLOGY.

divergent scales, all of one height, giving somewhat the appear-
ance of a little plush cap. In their life habits they vary much.
Some are leaf-miners, living between the upper and under sur-
faces, and each species eating out characteristic galleries that are
visible as irregular brown lines or blotches. Others are case-
bearers, making little houses of various shapes and texture,
which they carry about with them, and in which they live, pro-
jecting the head and anterior segments just far enough to feed,

Fig. 373.

Apple case-bearer, Coleophora nialivorella. — a, larval cases; b, larva; c, pupa;
d, adult moth.

but retreating at the first signs of disturbance. A few feed openly,
while others are borers in fruits, seeds, or even twigs.

Among the best known are the "clothes moths," — little, yel-
lowish creatures often seen flying in houses early in the evening,
and which generally arouse excitement and resentment in the
breast of the careful housekeeper, for she knows that her woollens
and furs are in danger. The caterpillars feed upon animal tex-
tiles of all kinds, and upon furs and feathers. They do not often
attack vegetable fibre like cotton or linen. Their habit is to
form a little flattened case of fibres from the material upon which
they are feeding, and this is lined on the inner side with silk. In
about three weeks the larva is full fed, changes to a pupa within
its case, and the moth, when it emerges, leaves the empty shell
protruding for half its length. There are several species engaged

THE INSECT WORLD.

325

E^'y

-.t:

iD.

\t«'

%:^

[1,1

^ AT,

*!»— ^■^:«

326 AN ECONOMIC ENTOMOLOGY.

in this pleasant occupation, but they have habits so nearly sim-
ilar that there is no necessity for differentiating them here. As
to remedies, plenty of air, sunshine, and beating- will keep cloth-
ing free, or, having been made free, it can be wrapped in stout
paper in such a way as to make it impossible for the moths to
enter and to lay eggs, or for the young caterpillar to find a crev-
ice through which to crawl. A cotton or linen sack, if the material
is sufficiently dense, will afford almost equal protection. A
closet or trunk in which plenty of naphthaline crystals have been
strewn is also a safe place, and will be avoided by the moths, who
cannot live in such an atmosphere. Where the insects get into
carpets, they can be destroyed by saturating the infested spots
with gasoline, as this is exceedingly penetrating and fatal to the
insects wherever it touches them.

Another troublesome species is the Gelechia cereallella, or ' ' An-
goumois grain moth." Its larva bores into the kernels of wheat,
rye, or corn, a single grain of wheat sufficing to bring one to
maturity, while in a grain of corn two or three, or sometimes
even four, larvae find sufficient nourishment, though two is, per-
haps, the rule. The insects sometimes lay their eggs upon the
grain in the fields, and when it is cut and brought into the barn
they continue breeding in the mow so long as it remains there.
Corn-cribs frequently become infested, and the insects breed as
long as the temperature remains mild. Where grain is threshed
and bulked the upper layers may be infested, but the insects are
not able to get in very far, because the moth is unable to escape
through any heavy layer, becoming worn out and dying before
reaching the surface. The insect is much more troublesome
southward than it is in the north, where the cold weather checks
breeding before it has an opportunity to do much damage ; but
in regions where the temperature in the barns is moderate
throughout the winter it frequently does great injury. The
best remedy is threshing and bulking the grain as soon as pos-
sible, covering the bins to keep out the insects. If infection is
noticed, it can be easily checked by evaporating bisulphide of
carbon in a dish upon the surface. The vapor is heavy and
sinks through it to the bottom, effectually clearing out any in-
sects that may be present. In corn-cribs the bisulphide can also
be used, but the crib must be temporarily closed by canvas or

THE INSECT WORLD. 327

sheeting, so that the vapor may become effective before it escapes.
It has been found by experiment that grain can be exposed to
this vapor for a considerable time without losing in germinating
qualities, but seed wheat should be, if possible, kept free from
such insects. It should be selected early and kept in insect-tight
vessels until needed for use. Open corn-cribs should be placed
in such a way as to get the benefit of all the cold weather there
is, and thus the multiplication of the insects will be checked so
early that no serious damage will be done.

There are other species of Tineids infesting cultivated plants,
but few are widely distributed and at the same time injurious.
In most cases the application of arsenites to those forms feeding
openly upon plant tissue proves more or less satisfactory, while
against those feeding upon stored products we can use the
bisulphide of carbon.

CHAPTER VIII.

THE DIPTERA, OR FLIES.

The term Diptcra means two-winged, and members of this
order are separable from all other insects by possessing, nor-
mally, only a single pair of wings. These are borne by the
middle segment of the thorax, and are, therefore, the first pair ;
the second or hind pair are reduced to little club-like processes
called " halteres," "poisers," or " balancers." Their function
is supposed to be indicated by the last of these terms, — i.e., to
aid the insect in directing its flight and maintaining its position in
the air. The members of the order are, therefore, easily recog-
nizable in most instances, but the reference of individual speci-
mens to the proper place in the system is a matter of greater
difficulty. They are mostly of moderate or small size, sometimes
quite fragile, and the character of the wing venation, upon which
much reliance is placed in scientific classification, is not readily
made out, except by the special student. Yet a litde patience
will generally lead to the proper group, and the habits or life his-
tory may then be used to determine more closely.

328 AN ECONOMIC ENTOMOLOGY.

Before taking up the more typical forms, we may briefly con-
sider the Aphaniptera, or fleas, which are usually considered as
flies that have lost their wings as a result of parasitic habits.
They are small, transversely flattened creatures, usually brown
in color, with small heads, piercing mouth parts, and the merest
rudiments of wing-pads. To replace wings, they are furnished
with greatly developed posterior legs fitted for jumping, and in

Fig. 377.

Rabbit flea, much enlarged.

proportion to their size their leaps are wonderful. They live in
the adult stage among the hair of warm-blooded animals, sucking
blood, their form enabling them to move about easily in even the
thickest fur. So also the position of the spines clothing the
body is such that every effort of the insect pushes it forward,
which accounts for the difficulty in holding a specimen when
captured.

The larvae are whitish, small, worm-like creatures, almost cylin-
drical in form and with small brownish heads which bear fairly
well developed mouth parts. They live upon partly decayed
matter in or near the lairs of the animals upon which the adults
feed, and the eggs are probably dropped at hap-hazard by the
females while the host is at rest. A rug used as a bed for a dog
or cat may be found full of eggs at almost any time during spring

THE INSECT WORLD.

329

or summer, the larvce finding food in any dust or dirt near by.
The spaces between the boards of floors are often filled with them,
and a little pile oi moist sawdust or shavings may harbor
myriads. This led to a quite wide-spread and at one time popu-
lar belief that under such circumstances the insects were sponta-
neously generated. The period of development is very brief,
and under favorable conditions a building may swarm with fleas
in a month or two. No species of flea specifically infests man
in this country, though the Ceratopsylhis serraticeps oi \.\iQ. house-
hold dog and cat often bothers him a little. In tropical and
subtropical countries several species attack him as readily as
they do any other warm-blooded animal.

Where a house becomes infested, the dogs or cats, if any,
should be washed with carbolic soap every other day to kill the
adults on them, and if the animals be allowed to run throughout
the house they will in a few days attract all the fleas to them-
selves, where they can be dealt with. The sleeping rugs of the
animals should be thoroughly beaten or shaken out-doors every
day, and the most rigid cleanliness should be everywhere
observed.

Where dogs or cats are not available as traps, a liberal applica-
tion of gasoline, following a thorough cleaning up, is the best
remedy. It should be poured into every crevice in the floor and
along the base-boards, and it will kill every larva and adult with
which it comes into contact. The liquid is exceedingly inflam-
mable, and must be used with that fact borne in mind. Pet
animals can be cleaned by a free and frequent use of carbolated
soaps or vaseline.

In hot countries fleas are often serious pests, not only to man
and his pets, but to fowls as well, young chickens being fre-
quently killed by the great numbers clustering around their
heads. Here the free use of carbolated vaseline is indicated to
keep off the insects and to act as an effective healing agent.
Cleanliness in its strictest form in the coops and houses is always
indicated.

Rather more serious pests are the so-called "jigger" fleas,
species oi Sarcopsylla, or Vermipsylla, the females of which work
their way under the skin, often of the feet of man, causing an ul-
ceration in which the eggs and larva; develop. If the case is

330 AN ECONOMIC ENTOMOLOGY.

neglected, amputation sometimes becomes necessary. Where
shoes are worn, the insects do not often succeed in reaching their
favorite points of attack ; but if they do, a prompt use of the
needle or knife or a mercurial ointment will prevent trouble. A

Fig. 378.

'^ y\^^&[" ?i&'!i,Sarcopsylla penetrans. — Female distended with eggs, from side and front.

Fig. 379.

moist quid of tobacco bound over the infested spot usually re-
sults in killing the insects, so that the wound can be cleaned and
left free to heal.

The metamorphosis of the fleas is complete, like that of the

true flies.

The most obvious division among
the true flies, for our purpose, is
based upon the character of the an-
tennae, or feelers. There are two
series, those with long horns or feel-
ers much exceeding the head, and
those with short horns, having usu-
ally only two or three visible seg-
ments, one of which is often fur-
nished with a specialized bristle, or
' ' arista. ' ' The divisions are by no
means sharply limited scientifically,
but are sufficiently distinct for the
species of economic importance.

The Tiptdidce, or ' ' crane-flies, ' '
is the first family of economic inter-
est, and its members are recognizable by their resemblance to
exaggerated mosquitoes. They are usually quite large, with
many-jointed, slender, thread-like antennae and scarcely shorter
maxillary palpi. The legs are abnormally long and ungainly,

Antennae in flies. — a, tip of plu-
mose antenna ; b, joints verticil-
late ; c, aristate, the arista bare ;
rf, arista plumose at base ; e, arista
plumose to the tip.

THE INSECT WORLD. 33 1

and the wings are narrow, so that the insect is awkward in ap-
pearance, as well at rest as in its flight, which is slow and heavy.
The flies are most frequently seen in low, rank meadows, or
along ditches or sluggish streams, flying preferably during the
morning and late afternoon hours. The larvae are slender, cylin-

FiG. 380.

A crane-fly, Pachyrrhina species.

drical, somewhat worm-like, of an extremely tough, leathery
texture, and live underground on the roots of grasses, or in de-
caying wood. In Europe they are known as "wire-worms,"
and are often seriously injurious ; but in North America none of
the species have as yet proved very troublesome. It is probable
that intelligent farm practice Avill be sufiicient to control any of
the species likely to become injurious with us.

33^

^N ECONOMIC ENTOMOLOGY.

To the family C2dicid(Z belong the mosquitoes, characterized
by a slender body, long legs, long antennae, and a small head

with mouth parts usually ex-
tended to form a beak or pro-
boscis. In the male the probos-
cis contains a single lancet only,
not fitted for puncturing animal
tissues, and the antennae are plu-
mose ; in the female a series of
five slender, bristle-like lancets
forms an effective piercing struct-
ure, and the antennae have the
joints furnished with a few bristles
only. The wings are slender and
scaly along the veins.

The species are quite numerous,
and while most of them are pests
of the first order, a few seem to
feed on other than animal juices.
The more common species be-
long to the genus Cidex, in which
the wings are unspotted, the palpi of the female are shorter than
the beak, and the body is held parallel with the surface upon
which the insects rest. The species of Anopheles are fewer in
number, but are of relatively greater economic importance,
because they have been proved to be intermediate hosts for the
parasites causing ' ' malarial' ' fevers. They are larger, as a rule,
than Culex, the wings are more or less spotted, the palpi in
both sexes are as long as the beak, the body is more linear and
is held at an angle to the surface upon which it rests, the beak
directed to a point almost midway between the fore and middle
legs.

Some of the species of Culex fly or allow themselves to be
carried by the wind for long distances, so that they occasionally
appear as pests many miles from any possible breeding-place.
The mode of hibernation varies : in Anopheles and some Culex
the female adult survives ; in other species of C^dex the eggs lie
over in suitable localities, and in one instance at least the partly-
grown larva lives through the winter.

Lan'a and pupa of the Culex pungens,
enlarged ; with anal flaps of pupa yet
more enlarged. (From Howard, Bull. 25,
n. s., U. S. Dept. Agl., Div. Ent.)

THE INSECT WORLD.

333

The larvse are commonly known as " wrigg^lers," and are of
two general types, — one usual in Culcx and its allies in which the
head is held down in the water and the tail or anal siphon is kept
at the surface ; the other peculiar to Anopheles, in which the body
rests for its full length on the surface.

All the larx'ce breathe through a single spiracle at the end of
the anal tube or siphon, and most of them must come to the
surface at rather short intervals to secure the necessary supply of
air. When startled they make their way through the water by a
peculiar jerky or wriggling motion, which gives them their com-
mon name.

Eggs are laid in various ways : sometimes singly on water or
on vegetation in water, or in damp places where water is likely
to come ; sometimes they are laid in masses, forming "boats,"
which float on the surface of the water, and this is the habit of
our most common species. Under proper conditions the eggs
hatch quickly and- the larvae develop in accordance with the
temperature ; a week or ten days being sufficient to carry the
insects from 'i^^ to adult in midsummer.

The lar\a must have water for its development, but there is
none so foul and none so salt that some species does not breed in
it. There is no space here for methods of dealing with these
pests ; but measurable exemption from annoyance may be secured
by a free use of the oil of citronella on exposed parts of the body.

Mosquitoes occur all over the world, and they are quite as
numerous and troublesome in the arctics as they are in the tropics.
In fact, the climatic peculiarities of parts of the frigid zone, giving
a short hot summer over a surface soaked with water from melting
snow, produce conditions which favor their development in great
numbers. In permanent ponds or streams their natural enemies,
of which there are many, keep them down to insignificant numbers.

Closely resembling mosquitoes in appearance are the Chiro-
nomidt£, which may be recognized by the naked wings and by
having the thorax produced so as to hide the small head fi-om
above. The antennae are feathered in both sexes, those of the
male strikingly plumose. To this family belong the gnats or
midges which may sometimes be seen dancing in swarms in the
evening only a few feet above ground, generally early in the
year and in damp places. The larvae are mostly aquatic, and

334

AN ECONOMIC ENTOMOLOGY.

never economically important. The minute species of Ceratopo-
gon are furnished with piercing mouth parts, and are often ex-
tremely irritating, but otherwise the adults are harmless, unfitted
for blood-sucking. They are known as ' ' sand-flies, " " punkies, ' '

"gnats," "midges," and by
Fig. 382. other names, some of which

are applied indifferently to spe-
cies of diverse families.

The "fungus gnats" of the
family MycetophilidcB are also
small, mosquito-like creatures,
but more compactly built, with
shorter abdomen, stouter body
and legs, and antennae that are
not plumose or feathered in
either sex. They are smoky
or blackish in color, as a rule,
and frequent decaying vegeta-
ble matter or fungi, in which
the larvae feed. The latter are
slender, white, worm-like creat-
ures, with a distinct black head, and usually feed together in
considerable numbers. They sometimes develop a curious wan-
dering habit when full-grown, marching in rope- or ribbon-like
aggregations an inch or two wide and from six to ten inches
in length. Some bands have been observed from four to five
inches wide and twelve feet in length, piled up from four to six
deep ! Ordinarily no injury is done by these insects, which are
rather scavengers than otherwise ; but one species of Sciara
becomes a serious pest to mushroom growers, eating into the
plants and utterly ruining them. In fact, in many localities it
is simply impossible to grow mushrooms after warm weather
sets in. Measurable exemption may be secured by keeping the
houses or cellars tightly closed and fumigating frequently with
tobacco or pyrethrum to kill the flies. In a cellar the flies al-
ways get to any window or other source of light, and great masses
can be killed in such situations by a fine spray of kerosene emul-
sion diluted ten times.

Quite recently Mr. Hopkins, of the West Virginia Experiment

Chii onomus species, male, enlarged.

Till: IXSECT WORLD.

335

Station, has found a species of this family concerned in j)rochicing
a form ol potato scab in that State. He has named it Epidapus

Fig. 383.

Sciara tritici. — a. larva; b, c. pupa from below and side; d, female fly; e,/, tips of
female and male abdomen.

scabci, and beheves it to Ijc responsible for much of the injury
usually ascribed to the germ disease. This may be locally true,

Fig. 384.

Epidapus scabei. — Wingless female and structural details.

but I have never found any trace of the insect in New Jersey,
though I have examined many hundreds of scabby potatoes for

33^

AN ECONOMIC ENTOMOLOGY.

Eggs and larva of Epidapus
scabei, much enlarged.

that especial purpose. Fortunately, the measures used to prevent
the scab due to the fungous disease seem to destroy the insects as
well ; hence the method of distinguishing
between the two is not important.

In the family CecidomyidcB, containing
the midges, or "gall-gnats," we find the
most injurious species of the order. They
are also mosquito-like in appearance, but
usually very small, with very long an-
tennse, which in the males are clothed on
each joint with whorls of fine hair. The
larvae are ovate, quite broad, and a little
flattened, the segments well marked, and
the apparent mouth parts formed in
many species by a peculiar horny pro-
cess which is known as the "breast-
bone," from its situation. The species
are numerous, and the larval habits and
life histories are very diverse. In most
cases growing vegetable tissue is the
food, and, as a rule, a more or less marked gall-like swelling
indicates the location of the larva.

The most widely known species is the "Hessian-fly," Cecid-
omyia destructor, one of the most serious enemies of wheat,
actually inhibiting its cultivation in some localities. The adult
is rather large for this family, smoky brown in color, and appears
late in the season, usually after the wheat is well above ground.
Eggs are laid on the young plants, and the larvae work their w^ay
into the stem at or near the surface, causing a slight gall or swell-
ing and a deformity in plant growth. When winter sets in full
size has been reached, and the "flaxseed" stage is entered
upon, — so called because of its superficial appearance, though it
is really the brown, dry, and hardened larval skin itself. In
spring the pupa is formed, and soon afterwards the adult appears,
ready to oviposit again in the now rapidly growing wheat. The
flaxseed stage is again formed low down in the stalk before har-
vest, so that it usually remains in the stubble when the grain is
cut. There it rests until the new wheat sprouts in fall, though
flies may be found all summer, and it is more than likely that

Fig. 3S6.

The Hessian-fly, Cecidomyia destynctor.—On the left a healthy stalk of wheat, and on the
right one infested at li by Hossian-fly, sho\vinjj;the galls, a, egg; b, larva; c, "flaxseed;"
d, pupa, all very much enlarged ; e, fly ovipositing on leaf, natural size ; /, female, and g,
male Hessian-fly, much enlarged ; :', the parasite, Merims destructor, much enlarged.

22 337

338

AN ECONOMIC ENTOMOLOGY.

certain grasses also sustain the species in the interval between
harvest and seeding.

The injury is done by stunting and aborting the wheat plants
in the fall, and in dwarfing stalks in the spring or so weaken-
ing them that they fall or ' ' lodge' ' readily, preventing thereby
the development of the ' ' ear' ' or of the grain in it.

Insecticide applications are hopeless, and modified farm practice
is the only satisfactory measure within our power. Very late sow-
ing in the fall — as late as it is safe to do so — will force the insects to
oviposit in volunteer shoots or grasses, and the later germinating
crop remains exempt. As far as possible, infested stubble should
be ploughed under deeply immediately after harvest to destroy a
large percentage of the " flaxseeds," or it should be burnt.

Another, related pest, is the "wheat-midge," Diplosis tritici,
which in the larval stage feeds upon the kernel of the grain,
dwarfing it or causing its entire abortion. This larva is quite
red in color, and the parent midges are about in June, oviposit-
ing in the blossoms or on very young kernels. In this case
also deep ploughing after harvest is advisable, and after threshing
all chaff should be disposed of so as to destroy all chance of life
for such insects as may yet be in it.

The "clover-seed-midge," Cecidomyia leguminicola, is also a
dangerous enemy in some localities where seed rather than hay
or fodder is desired. The midges lay their eggs in the flowers,
and the resulting larvae feed upon the forming seed, utterly de-
stroying it. Where the insects are known to occur, cutting an
early crop just when it is in full head and depending upon a sec-
ond crop for seed is good practice. The midges oviposit in the
flowers of the first crop, and those of later date will be practically
exempt. The cutting can be high, so as just to include all the
heads, which will be rapidly renewed from the vigorous stalks
remaining. Fall ploughing infested fields is good practice, or
ploughing under after cutting, and planting some cultivated crop
that involves frequent stirring of the soil. The insects winter
just below the surface among the roots, and the practice above
suggested looks towards winter killing them. A liberal use of
lime and kainit after the crop is off is also good practice, and
will kill many of the larvae then barely beneath the surface and
not yet in their cocoons.

THE liXSECT WORLD.

339

The " pear-midge," Diplosis pyn'vora, is an imported species
appearing with the first buds of early spring and ovipositing in
them as soon as they begin to show white. The young larvae
make their way to the ovary or seed-capsule of the setting fruit,
and when this reaches the size of a nut, growth stops. The pears
are then irregular in shape, a little knotty, and filled in the centre
with a mass of orange-yellow larv.ne. In June these become full-
grown, leave the

pears, — which now ^^'^'- ^^"•

crack open and de-
cay,— and drop to
the ground, beneath
the surface of w^hich
they pass the winter.
The insect is es-
pecially fond of the
' ' Lawrence' ' va-
riety, and where
such can be found
in sufficient num-
bers, all others are
exempt. The way in
which this species
can be controlled
is by treating the
ground beneath in-
fested trees with a
heavy top-dressing
of kainit, — say one
ton to the acre, — appHed between the middle and end of June.
Planting "Lawrence" trees as traps and applying the above
remedy to the soil beneath them will decidedly lessen the injury
to the balance of the orchard, or their fruit may be gathered
and destroyed in May, with all the contained larvae.

Not all the gall-midges are injurious, however. Many species
form galls or other distortions of growth on weeds or other plants
of no special economic interest, or in such a way as to cause no
real injury, and a few are actually predaceous and directly bene-
ficial. Such is the species that feeds in the Phylloxera leaf-galls

The pear-midge, Diplosis pyrivora. — a, female adult ;
pupa ; other references are to structural details.

340

AN ECONOMIC ENTOMOLOGY.

Fig

on the grape, and not improbably other species occasionally
found in leaf-galls are predatory upon the original producer. As
a whole, the gall-midges are to be regarded as dangerous, and
the measures to be adopted against them are, in almost all im-
portant cases, modifications of farm practice, since they are usu-
ally beyond the reach of insecticide substances.

This closes the series of long-horned, mosquito-like flies, none
of which are of direct benefit to the farmer, while not a few are
among his most dangerous foes. As a whole, the species should
be looked upon with suspicion and closely investigated when
they occur in numbers great enough to attract attention.

Quite early in the season we may see large numbers of loose-
jointed, ungainly flies of moderate size, with long, stout legs,
heavy body, short, stout, though many-jointed antennae, and

often, in the female, a ridic-
ulously small head. In
color they are black, or
black and yellow, or red.
These belong to the family
BibionidcB^ sometimes
called ' ' March-flies, ' ' from
their early appearance ; and
while their larvae are some-
times feeders on grass roots,
they never become eco-
nomically important. They
are mentioned here because
their early appearance in
great numbers sometimes at-
tracts attention. They are
often plentiful in orchards
just when the blossoms
open, but seem not to be
of any service in poUen-
izing.
are in some localities serious pests
The "black flies" of the North-

Bibio albipciniis. — a, male; c, its head; b, fe-
male ; rf, her head ; c, f, g, other structural
details.

" Black flies," or "gnats,"
to man and domestic animals,
ern woods and the "buffalo-" and "turkey-gnats" of the South-
ern and Mississippi States are good examples. They are rather

THE INSECT WORLD.

341

undersized, chunky flies, dark in color, with the thorax well
developed and somewhat produced forward so as to partially
conceal the small head from above. Though the head is small
,in proportion to the insect, the mouth parts are exceedingly
well developed and furnished
with a formidable array of
lancets for puncturing and
blood-sucking. They belong
to the natural family Sinm-
/iidce, and are distinguished,
in addition to the peculiari-
ties enumerated above, by
short, broad wings, in which
the venation is almost obso-
lete, except along the front
margin.

The larvae are curious little
creatures, living under water
in rather swiftly flowing
streams, clinging to rocks,
sticks, or logs, and feeding
upon vegetable matter. They
are furnished with sucker-like
structures at both extremities,
by means of which they cling
to their resting-place, and move from place to place, breathing
by means of tracheal gills.

In favorable localities these insects may develop in enormous
numbers, and, flying in the bright light of mid-day, attack any
warm-blooded animal that comes in their way. Such is their
number sometimes that they completely cover the animal at-
tacked, first rendering it frantic by the pain inflicted and soon
after weak from the loss of blood. Eventually death ensues,
whether the animal be a man or a mule, unless repellents are
employed or a rapid retreat out of the infested territory is
accomplished.

Where the insects breed in shallow streams, the larvae attached
to stones, nothing can be done to check development, and the
mixture already recommended for mosquitoes — viz., oil of tar,

Buffalo-gnat.

342

AN ECONOMIC ENTOMOLOGY.

Fig. 390.

oil of pennyroyal, and sweet oil — must be resorted to for man,
while fish oil, with an admixture of crude carbolic acid or creo-
sote, will be found effective for animals. Smudges are often
used where buffalo-gnats are abundant, and the
stock soon learn that in or near the smoke ex-
emption from attack may be secured. Where
„ the water of infested streams

is deep, undue multiplication
is frequently chargeable to an
accumulation of logs or other

)|^| ""^^^M^^^i^-^ material at certain points, af-

"^S\ fy^^lhv^ fording suitable locations for

LSii=^ l(^j«M"*\ |.j^g development of the gnat

larvae. In such cases much
good may be accomplished
and sometimes practical ex-
emption may be secured by
cleaning out the streams and
thus destroying the breeding-
places. Stationary rafts of logs
should not be allowed, and the
surface should be kept as free as possible of anything to which
the larvae can attach themselves.

The "horse-flies," or TabanidcE, comprise another set of
troublesome creatures, of medium or large size. They have
short, broad heads, enormous eyes, and short, though many-
jointed, feelers. The abdomen is oval, a little flattened, and the
body is convex and powerful. The mouth parts are well
developed, consisting of a series of five sharp-pointed lancets so
rigid that they readily pierce the skin and draw blood almost as
soon as they touch. These flies frequent woods or the edges of
woodland, sometimes low meadows or marshy places, and occa-
sionally prove serious pests to stock. They are often trouble-
some in woody roads, because with three or four of the large
black flies buzzing about, horses may be driven almost frantic.
Similar species occur in great numbers along the sea-shore,
where they are known as "green-heads." In some localities
they are known as "deer-flies," and some are called "golden-
eyed flies," having the eyes more or less banded or striped

Larva of buffalo
gnat.

Pupa of buffalo-gnat.

THE INSECT WORLD.

343

with metallic yellow or brown. The female only has the blood-
sucking habit, the males feeding usually upon pollen, and being,
therefore, rarely noticed, except by the collector. The larva;
are elongated, somewhat flattened creatures, some living in the
soil, some in water, and some in marshes, preying upon what-
ever comes in their way. In this stage they might possibly be

Fig. 392.

a 6

Horse-fly, Tabanus atraius.—a, larva ; b, pupa ; c, adult.

reckoned of some benefit, did they inhabit places frequented by
injurious insects ; but at best they are harmless, — unlike their
parents in this as in all other respects.

Horses driven through districts badly infested by these insects
should be furnished with a netting, and, if it is necessary to keep
the animals for any time exposed to attack, the fish oil and car-
bolic acid mixture already recommended can be used to repel
the flies. It need be applied only in such places as the animal
cannot conveniently reach with its tail, or which is not sheltered
by a netting.

Somewhat resembling "horse-flies" in appearance are the
members of the family Stratiomyiidce, or " soldier-flies," so called
because of their often bright bandings of green and yellow.
They have the same general shape but rather longer antennae,
with broader, much more flattened, abdomen. They are not
troublesome in any stage, and are referred to simply because of

344

AiV ECONOMIC ENTOMOLOGY.

Fig. 393.

An Asilid fly. — Erax bastardi
larva, pupa, and adult.

their resemblance to, and to distinguish them from, the " horse-
flies."

Another series of large species we find among the "robber-
flies" belonging to the family Asilidcz, and these are quite
different in appearance from any heretofore treated. The head is
prominent, very hairy, with rather short, several-jointed antennae,

and with a short, stout proboscis,
which is formed for piercing. The
body is robust, also covered with hair,
and the abdomen is long, slender, and
cylindrical, tapering very gradually to
the tip. The wings are long and nar-
row, the legs moderately long and very
powerful, densely clothed with spines,
while the tips of the tarsi are supplied
with unusually long and stout claws.
The insects are called ' ' robber-flies' '
from their habit of pouncing upon,
piercing, and sucking the juices of
other insects in mid-air, while holding
them with their powerful legs. We have a great variety of
species, some of them large and brightly colored, though the
majority are of a sober gray, varying sometimes to reddish,
sometimes to yellow, and only rarely becoming black, except in
the genus Laphria. Though predaceous, the insects can hardly
be called beneficial, because they rarely attack injurious species,
and in some cases become themselves injurious by attacking
bees. The late Dr. C. V. Riley records having observed a single
species kill forty bees in one afternoon. Professor Comstock
notes their feeding upon the cotton-worm, and undoubtedly
they do occasionally kill injurious insects, but can scarcely be
credited with being a factor of much importance in keeping down
troublesome forms. They never attack man or animals, although,
if carelessly handled, they are ready to sink their lancets into the
flesh of their captor. The larvae are also carnivorous, so far as
known, and live in the ground or in decaying wood.

Yet larger in size and of the same general shape are the mem-
bers of the family Midaidce. They are often contrastingly col-
ored, sometimes uniformly dead black or blue, though usually

THE INSECT WORLD. 345

relieved by a bright red or yellow band or similar marking.
The wings are quite generally blackish and the antennae are
clubbed at the tip, differing thus from the previous family. In
fact, the species are so peculiar that, having been once seen, they
can scarcely be mistaken. They are also predaceous in habit,
but not nearly so ravenous as the " robber-flies," besides being
much less abundant.

A very interesting family is that of the " bee-flies," or Bomby-
liidce, which derive their common name from the fact that they
are more or less covered with dense, diverging, whitish or yellow
hair, giving them a close resemblance to certain bees. Many of
the species occur in open places, hovering over bare spots,
especially in spring, and they may be found at other seasons
flitting from flower to flower, often poised in mid-air between or
over them. There are two rather distinct series, one of them
with robust species resembling a bumble-bee, and with a very
long tongue ; the other much more slender, the species re-
sembling flower-flies, with a much shorter proboscis and much
less contrasting colors. The former are typified in the genus
Bombylius : the latter belong to Anthrax and allied genera.
Their food is honey obtained from flowers, and the adults are at
least innoxious. Among the species that occur early in the year,
some are of direct benefit in the orchard, where they aid in pol-
lenizing fruit flowers. The hairs composing the vestiture are
furnished with little spurs or processes, or are twisted, so that
pollen grains adhere readily. They are especially useful in
cross-pollenation from their habit of flying considerable distances.
The larvae, on the other hand, are parasites, and distinctly bene-
ficial in many instances. They prey upon the larvae of Lepidop-
tera, including many of the cut-worms, and also infest the egg-
pods of grasshoppers, forming one of the effective checks of the
migrating or " Rocky Mountain locusts" in this country. They
are less beneficial when parasitic upon bees and other Hyme-
noptera, but altogether the family may be said to contain chiefly
useful species.

Sometimes we find in houses, under carpets, a slender little
larva nearly white in color, with a darker, rather indistinct, head,
but without obvious legs. It is usually looked upon with sus-
picion because of the locality in which it is found, but as a matter

346

AN' ECONOMIC ENTOMOLOGY.
Fig. :,94.

CL^

^■■\ . ,.--*«*-

i H- ^

Fig. 395.

Fig. 396.

Bee-flies. — Fig. 394, Aiit/irax hypomelas : a, larva; b, the fly pupa projecting from a
cut-worm pupa ; c, pupa ; d, adult. Fig. 395, larva, with details, of Systcechus oreas,
parasitic in grasshopper egg-pods. Fig. 396, pupa and adult of Systcechus oreas.

THE INSECT WORLD.

347

Scenopiiius ffnestvalis.

of fact it is predaceous in habit, and feeds upon the species
really infesting carpets and similar material. Thus, ' ' moths, ' '
the larva; of the "carpet-beetle," "fish-moths," and numerous
other insects likely to

occur in such situa- ^''^- •^97-

tions are destroyed by
it. From this larva
there comes in due
time a small blue fly,
a member of the family
ScenopinidcB^ slender
and somewhat flattened
in appearance, with yel-
low or reddish legs, and
this may be sometimes
seen upon the win-
dows. These larvae

have been often brought to me, and the little flies raised from
them hax'e always been Scenopinvs fenestralis, from which Pro-
fessor Comstock gives the group the name "window-flies."

The remainder of the Diptcra have the antennae short, rarely
more than three-jointed, and usually with a bristle or style, called
an "arista," which may or may not be feathered or plumose,
from the second or third joint. The first of the families to which
it is necessary to refer here is the Syrphidce, containing a large
number of species, most of them prettily colored, yellow, black,
or bronze, patterned and marked in many different ways. They
frequent flowers, hovering and often remaining suspended over
them in mid-air for some time, then suddenly darting away and
again returning. Their habits and appearance frequently give
them a resemblance to bees and wasps, and in some species this
is carried so far that they are easily mistaken for members of the
order Hymenoptera by those not familiar with them. As a rule,
the head is quite large, the body barrel-shaped, and the abdomen
a little flattened, varying from very slender to broadly oval in
shape. This abdomen is yellow and black, or bronze banded,
sometimes entirely bronzed, more rarely blue or green, but
nearly always brightly colored in some way. Some of the flies
have the body distinctly covered with hair, though generally this

348

AN ECONOMIC ENTOMOLOGY.

Fig. 399.

vestiture is confined to the thorax or trunk, and such species are
sometimes of use in pollenizing flowers. I have found several
species about fruit-blossoms in spring, moving from flower to
flower, and, adhering to the vestiture, I have found pollen grains
in considerable number ; so the insects are probably of some
importance in this direction. We have one very large species,
Eristalis ienax, appearing late in fall, often in houses, and so
closely resembling a honey-bee as to be generally mistaken for
one ; for which reason it has been called the " drone-fly." It is
frequent in greenhouses about the time
that chrysanthemums are in bloom, and
gardeners have assured me that pollen-
izing this flower is done by it entirely ;
hence they call it ' ' chrysanthemum
fly." It is not at all unlikely that this
is the case ; indeed, it is even proba-
ble, though sufficiently direct observa-
tions have not as yet been made in the
matter. In this connection it is inter-
esting to find that the body vestiture
of the Syrphids is often composed of
spurred and branched hair, similar to
that found in bees, and in the "drone-
fly' ' this character is especially marked.
As widely divergent as the flies
themselves are the larvae and their
feeding habits. In fact, there is no sort
of agreement ; and while some are pre-
daceous, feeding upon plant-lice or
other insects, many feed in living or
decaying vegetable substances, or in
the foulest excrementitious material.
Those forms that most concern the agri-
culturist are the feeders on plant-lice,
and these may be found at almost any
time during the summer in almost every
aphid colony, busily engaged in lessening its numbers. The
larvae are easily overlooked, as they are usually green or yel-
lowish in color, like the insects among which they feed. They

y<Z-^

Body vestiture of Eristalis
tenax : a, entire hair; d, c, d,
parts of same ; all greatly en-
larged.

Fig. w^.

Uee-flies and flower-flies. — a. Hoiiibylius sp. : b. h'oinbylius sp.'; c. Anthrax sp. ; d,
Kiistalis lyansvnsus : c, Eiistalis Irnax ;/, Eristalis saxorum ; g, Syritta pipiens. Some-
wlial enlarged. From a photoi;ra])li.

THE INSECT irOR/.D. 349

are wrinkled and hairy when examined with a magnifying glass,
soft in texture, thickened behind, and tapering almost to a point
at the head, which is marked only by a pair of hooks and a
little circular opening representing the mouth. They have no
legs, and move by extending the body forward as far as pos-
sible, then clinging with the anterior segments to the leaf or
twig, and drawing the balance to meet the head. Awkwardly
as they move, however, their progress is yet sufficiently rapid
for their purpose. When once a larva has established itself in
a colony of plant-lice, it never stirs until all in its immediate
vicinity are destroyed ; it then moves only far enough to bring
into reach additional prey, and so continues until no more re-
main. The female lays her eggs close to, or actually among,
an aphid colony, so that the larva finds food ready at hand
as soon as it is hatched. It grasps a plant-louse with the
mouth parts, lifts it from the surface, and sucks
its juices, leaving the creature to struggle for 'J^

a time, helplessly kicking its legs in mid-air.
When the juices are exhausted the empty shell
is dropped and another specimen is taken.
When full-grown, the larva draws itself up
into a humped mass ; the outer skin hardens, syiphus larva de-
darkens in color, and forms an apparently solid ^ounng a piant-

1 1 • 1 1 louse.

covering or coarctate pupa, beneath which the
true or soft pupa of the fly is formed. Several broods of these
predaceous flies occur in the course of the season, and they are
among the most important checks that nature has provided
against plant-lice increase.

Others of the species are not quite so useful, and occasionally
we have a form that is almost parasitic, living in nests of bum-
ble-bees or other Hymenopterous insects and feeding upon
their larvae. In such cases we often find that the flies greatly
resemble in appearance the hosts among which they live.
Among the feeders in vegetable matter we have a great variety
of form, but they are usually more or less maggot-like and
without legs. As they are not of particular economic interest,
no more attention need be paid them here. The larva of the
"drone-" or "chrysanthemum-fly," Eristalis teiiax, lives in
ijiasses of soft, decaying, or excrementitious matter. It is fre-

35°

AN ECONOMIC ENTOMOLOGY.

quently found in privies or cesspools, sometimes appearing so
suddenly and in such numbers that a suspicion is engendered
that the specimens have been passed by the individuals using the
out-house. In fact, I have on more than one occasion received
the larvae with the positive statement that this had actually
occurred. They are curious creatures, maggot-like in general
shape, with a long, extensile, tail-like appendage at the anal ex-
tremity. It is hollow or tube-like, and at the end is a spiracle,
the use of this telescopic tail being simply to keep the opening
above the surface of the filthy mass in which the insect lives, and
thus to secure a supply of pure air. The
larvae are called from this peculiarity ' ' rat-
tailed." The reason why the flies are
sometimes so abundant in greenhouses is
that somewhere in their vicinity, among
semi-liquid manure, the best breeding-
places can usually be found. Taken as a
whole, this family SyrphidcE contains no really noxious insects,
and many that are decidedly beneficial. It should be noted,
however, that the larvae of some species feed upon pollen, and
that others live in growing vegetable tissue ; hence it is not
impossible that in the future this general statement may have to

Fig. 402.

Fig. 401.

Rat-tailed X-Axvz-oi Etistalis.

Mesograpta poh/a.—L.a.rva, pupa, and adult; all enlarged.

be modified. One of the most common Eastern species, Meso-
grapta polita^ has been found feeding in great numbers in the
larval stage upon corn pollen, but without causing any real injury.
Passing over several small families interesting enough in them-
selves, but not of importance to the agriculturist, we reach the

THE INSECT WORLD.

351

little family Conopidic, which is not at all injurious, but rather
the contrary. Professor Comstock calls them "thick-head flies,"
and the term is not bad, because the head is usually very promi-
nent and as wide or wider than the body. The thorax is unusu-
ally short, and bears a long abdomen having the
basal joints very slender and the terminal joints Fig. 403.

enlarged, bulb-like, much resembling in appear-
ance that of certain wasps. The flies are moder-
ate in size, with the wings more or less brown or
clouded, and they may often be found on flowers
after midsummer, in company with the Hymen- _ . , ^ ,

^ I- J J Conops ttbialts.

optera, which they resemble. The larvae are
parasites, chiefly, it is said, upon bumble-bees and wasps, in
which case they are not beneficial ; but also on grasshoppers, in
which respect they deserve our most distinguished consideration.
Distinctly injurious insects we find in the family CEstridce, or
"bot-flies." These are usually of good size, sometimes even
very large, and peculiar by having the mouth parts almost
entirely aborted. Some of the species are very hairy, yellowish
in color, and with rather a pointed abdomen ; while others are
very plump, robust flies, blue or blue-black in color, often with
a whitish bloom like that of a plum, formidable in appearance,
though in fact entirely inoffensive in this stage. In the larval
condition they are known as "bots," and live beneath the skin,
in the intestines, or in the mucus-lined head passages of the
animals infested by them. Thus, the "horse-bot," Gast7'ophihis
equi, passes its life in the stomach, attached to the inner coat, and
there remains until full grown, when it releases its hold and is
passed in the natural way through the anus. It then crawls into
some convenient place just below the surface of the ground, or
even among rubbish on top of it, and changes to a pupa. The
adult lays its eggs on the hair, chiefly of the forelegs, at points
easily reached by the tongue of the animal in licking itself. The
eggs are thus removed, carried into the mouth on the tongue,
and so into the stomach, where the larvae hatch almost immedi-
ately and at once attach themselves. It is readily seen that this
habit gives us a certain possibility of controlling the insects,
because if the horses can be prevented from licking ofl" the eggs,
they never can reach the proper location for their growth.

352 AJV ECONOMIC ENTOMOLOGY.

Checking the animals up when in use accompHshes this, and a
spiked muzzle, so arranged as not to interfere with feeding, will
answer in the stable. Frequent brushing to remove the eggs is
useful in bot-infested regions, and lessens the number that can
reach the alimentary canal.

Numerous other species occur just under the skin of the
animals infested, and one of the best known of these is the " ox
warble," Hypoderma lineata. Here also the eggs are laid on
the hair and are licked off in the same way ; but the larvae, instead
of allowing themselves to be carried into the stomach, pierce the
oesophagus or other portion of the alimentary canal, and work
their way through the muscular tissue to a point just below the
skin. There they fix and increase in size, causing the swelling
and suppuration so familiar to farmers in some localities. Of
course the means just mentioned for preventing the entrance of
stomach bots are also applicable in this case to avoid infestation.
Where bots are already established on an animal, the best method
is to incise the skin and press out the larva beneath it, or use a
mercurial ointment, which, penetrating into the wound, will kill
the larva, so that it can be readily pressed out later, or will sup-
purate out easily. Some species of bot-flies undoubtedly lay
their eggs on the skin of the animals at the points where the
larvae actually hatch, and the latter work their way through just
there and form the swelling. Sometimes special organs are
attacked, as in the chipmunks and squirrels, where the testes of
the males are selected and the creatures are actually emasculated.
The fly has, therefore, been called the " emasculating bot," Cuter-
ebra emascidator. In rabbits a species is found close to the
anal opening, and in fact most animals are more or less subject
to bot attack. Even man is not exempt, and several cases have
come under my observation where flies had laid their eggs on the
skin and the bots had developed considerably before the charac-
ter of the trouble was understood. In southern countries this is
much more likely to occur than in the north, possibly because a
much greater part of the body is there habitually exposed.

Sheep suffer from a species known as CEstrus ovis, which lays
its eggs on or in the nostrils. The larvae make their way through
the nasal passages in the mucus beneath the skin, and even into
the horns. They are often very troublesome, and cause one

THE IXSECT WORLD.

353

form of the disease known as "staggers," which is sometimes
extremely destructive to herds.

From this description of the Hfc histories, so briefly given, it
appears that our efforts to avoid injury must follow in the direc-
tion of prevention. As against the species that must first be
taken into the mouth, the mechanical ways of preventing a
horse or an ox from licking any part of the body will prove suffi-
cient ; or frequent brush-
ing will at least moderate I'^it"-- 409-
the injury.

In the case of the
sheep-bot the matter is
more difficult, because the
flies are very persistent,
and encircle the animals
until they get an oppor-
tunity to dart to the nos-
tril and deposit upon it
an &^^ just ready to
hatch, or already hatched,
so that either immedi-
ately or in a very short
time the maggot makes

its way up along the mucous membrane as far as the passages
allow it to extend. All sorts of devices have been adopted to
prevent this, but none are entirely satisfactory. Tar has been
used as a repellent, smeared on the nose, and .vith more or less
success. It is probable that fish oil and oil of tar, or carbolic
acid, would answer the same purpose. Powdered tobacco, used
to induce the sheep to sneeze and thus dislodge any maggots
that had already made their way in, has also been more or less
satisfactory. In the case of recently infested animals, a brush
dipped in turpentine and carefully used in the nostrils, so as to
reach attached larvae and kill them, is sometimes found useful.

The family Muscidce is the largest in number of genera and
species in the order as well as the most difficult to classify. The
common "house-fly," the " blue-bottle," and the "flesh-fly"
are examples, and may be considered as typical forms, which
most of the species resemble ; not necessarily in color or mark-

23

The sheep-bot, CEstius ovis. — i, 2, flies ; 3, pupa ;
4, 5, full-grown larva ; 6, young larva.

354

AN ECONOMIC ENTOMOLOGY.

ings, but in general type of structure. It is almost impossible
for any but the special student to distinguish between even the
sub-families, and yet these differ greatly in habit, some being
decidedly injurious and others as decidedly beneficial in the
larval stages. One of the peculiarities of all the members is very
short antennae, in which the terminal joint is long and stout and
furnished with a bristle or arista attached near the base. The
modifications of this bristle aid in distinguishing the groups.

The Tachina flies, for instance, have the bristle entirely bare,
though otherwise many of them resemble the common "flesh-
fly" or the "blue-bottle." They are generally rather large,
robust in appearance, always bristly, and sometimes formidable
looking from the array of sharp spiny points projecting in every
direction. They are parasitic in habit, largely upon caterpillars,
and among them perhaps preferably upon cut-worms. Fre-
quently, where the latter are numerous, a large percentage will
be noticed with one or several little white eggs attached on the
anterior segments, just back of the head, in such a position that the
larvae cannot possibly reach or destroy them. These eggs hatch
in a very short time into little maggot-like creatures that at once
bore through the skin of the caterpillar and live within its body,
feeding upon the fatty masses and muscular tissue not absolutely
necessary to life. When the maggots are full-grown and the
welfare of the caterpillar is no longer a matter of importance to
them, they feed on regardless of consequences, and the creature
dies. The maggots, sometimes without even attempting to get
out of their host, then change to barrel-shaped pupae. This is
accomplished by a contraction of the larval skin, which hardens
and becomes brown in color, releasing its hold at the same time
on the forming (true) pupa beneath. Occasionally the maggots
leave their host and make their way a little below ground to
pupate. Some of our large caterpillars attain their full growth
with as many as thirty or even more of these maggots feeding
upon their vitals. Some of the flies are very handsome and
strikingly colored, as, for instance, the Tachina vivida, in which
the abdomen is bright red, set with black spines, — a very remark-
able looking species. Others are black, the abdomen banded
with yellow ; but as a rule they are of a modest gray color, the
thorax rather obscurely streaked with blackish brown or gray.

Fic. 413.

JrlG. 410.

Muscid flies. — Fig. \\o, Exorista flavicauda, yellow-tailed Tachinid. Fig. 411, Ne-
morea leucanicE, Tachinid on cut-worms: larva, pupa, adult, and the white eggs on
the anterior segments of the caterpillar. Fig. 412, Lydella doryphoree , Tachinid on
potato-beetle. Fig. 413, common flesh-fly, Sarcophat^a carnaria. Fig. 414, the blow-
fly, Calliphora vomitoria. Fig. 415, screw-worm, Lucilia macellaria : a, 6, c, larva and
details; rf, pupa ; <?, adult ; /, head from side. All are enlarged, and Fig. 413 very
much so.

355

356 AN ECONOMIC ENTOMOLOGY.

These flies are among the most effective of nature's checks to
caterpillars, especially cut-worms.

The "flesh-flies" greatly resemble the Tachina flies in ap-
pearance, but the arista or bristle of the antennae is feathered
towards the base and is bare only at the tip. Some of these
species also are parasitic. Others have larvae that live in excre
mentitious material, in fruits, in meats, or in decaying animal or
vegetable matter generally. Such species usually produce their
young alive, or at least as eggs just ready to hatch, and the
majority are scavengers. None of the members of this family, so
far as I am aware, are injurious, and they are always beneficial to
the extent, at least, of assisting in the removal of offensive matter,
animal or vegetable.

The typical Muscids differ from the other species in this series
by lacking the spines of the thorax and abdomen, or having them
confined, in a very reduced state, to the tip of the abdomen only.
The arista or antennal bristle is feathered to the tip. The house-
fly is one of the best known of all insects the world over, and
there seems to be no region where it does not occur and is not
more or less annoying. It winters in our houses or out-buildings,
hiding in some sheltered spot in cellar or attic, or remaining
more or less active in our carefully warmed rooms. During the
early days of spring a few specimens make their appearance here
and there, sole survivors of the swarms of the preceding year.
These are mostly females ready to reproduce, and they lay their
eggs in any convenient pile of horse manure ; or, if that is not
available, in any decaying animal or vegetable matter. The
maggots hatch in a day or two, in a week or ten days are full-
grown, change to pupae, and in a very few days more a new
brood of flies is matured, already sufficient in numbers to become
more or less annoying. This process is repeated time and again
during the season, and the insects increase in numbers until after
midsummer, when they seem to lose activity to some extent,
although breeding until cold weather actually sets in. House-
flies are not injurious in any true sense of the word, although they
are distinctly annoying and may become dangerous by trans-
ferring disease germs from one point to another ; as when, after
alighting and feeding upon the sputum of a consumptive, they
tickle the nose of a healthy sleeper a few minutes thereafter. So

THE INSECT WORLD. 357

blood poisoning may be set up by a fly which has been feechng
upon a putrefying carcass and then feeds upon an abraded sur-
face or a cut or bruise on man. This, however, is not a common
occurrence, and perhaps as a scavenger the insect is about as
useful as it is annoying. A single female produces on an average
about one hundred and fifty eggs, and this, with the short period
required to bring them to maturity, accounts for the enormous
increase of the insects. After a fly has attained this stage it
never grows more, and a small fly never makes a large fly, any
more than the progeny of a large fly is ever a small fly.

The "blow-fly," Calliphora voinitoria, is the largest of the
common species abundant enough to attract attention, and this
has the body of a deep blue, almost black, color, the abdomen a
little lighter and somewhat more shining. It is an obtrusive
creature and noisy withal, especially when flying about on the
windows or bumping against the ceilings of a room, making its
presence obnoxious in more ways than one. Its eggs are laid on
all sorts of animal and vegetable matter in an incipient stage of
decay. Meat exposed in summer is almost certain to show, in a
very short time, little piles of elongate white eggs scattered over
the surface here and there. Fish are especially subject to attack,
and I have myself had the experience that a little string of fish
laid in the shade of a bush on the bank was covered with such
eggs before I was ready to go home. Of course they could be
readily washed off, and it is not usual for this insect to retain the
eggs until they hatch within the abdomen, yet I have found
specimens that have done so. This species also requires but a
very short period for its development, and its rate of increase is
so great that it has given rise to the saying that a pair of flies
will devour an ox more rapidly than will a lion. A carcass left in
the fields during midsummer becomes, in fact, in a few days a
mass of maggots, which soon leave nothing but hide and bones.

A somewhat smaller species than this blow-fly, of a very much
brighter green or bluish color, with four longitudinal lines on the
thorax, is the "screw-worm" fly, Lticilia macellaria. This is a
common species throughout a large portion of our country, and
ordinarily feeds upon dead or decaying animal matter. Under
some circumstances, however, it attacks living animals, and in
the Southern and Southwestern States occasionally becomes a

358 AN ECONOMIC ENTOMOLOGY.

terrible pest. On such occasions it lays its eggs on man or
animals wherever there is the slightest trace of a wound, bruise,
or offensive discharge of any kind. The larvae bore directly into
the living flesh, causing intense pain as well as suppurating sores.
Living larvae are produced as well as eggs almost ready to hatch,
and into any opening from which there is a discharge of any
kind eggs may be deposited. Sleeping humans with an offen-
sive breath, or with a fetid discharge from the nostrils or mouth,
have had eggs laid at theSe points, and larvae have made their way
into the head, in some cases causing the death of the individual.
Eggs have also been laid in the ears of uncleanly people, and the
channels and passages of this organ have been penetrated into the
head and destroyed. Animals are troubled in the same way, and
where the insects are abundant, their attacks often become fatal.
The only remedy is cleanliness. Wounds, even of the most
trifling nature, on cattle should be smeared with an antiseptic
ointment. As far as possible, all materials in which the flies can
breed should be destroyed ; no accumulation of animal refuse
should be allowed under any circumstances, and by strictest at-
tention to surroundings, the breeding of the insects should be
prevented. Attacking live animals is not a usual habit, although
very readily assumed when the insects become abundant.

Another insect, a trifle larger than the house-fly and much
like it in appearance, though a little more robust, is the ordinary
stable-fly, Stomoxys calcitrans. This has the mouth parts formed
for piercing, and annoys animals by alighting upon and sucking
the blood of parts that cannot be reached by them with head or
tail. Sometimes these insects also attack man, especially late in
the season or in heavy weather. They have an especial fondness
for human shanks, and readily bite through stockings ; sometimes
through trousers as well. This bite is painful, though it rarely
leaves a swelling or perceptible inflammation. The larvae develop
in horse and cow manure, and their increase in stables can, there-
fore, be checked to some extent by promptly removing and
placing this in pits, or mixing with plaster or other material that
will absorb the moisture and fix the ammonia.

A close ally of the stable-fly is the so called "horn-fly,"
Hcematobia serrata, a recent introduction into the United States,
which has spread over the country with almost phenomenal

THE INSECT WORLD.

359

rapidity. This insect derives its common name from the fact
that it seems to prefer clustering in great numbers at the base of

Fig

Horn-fly,

Hamatobia seriata. — a, egg; b, fly;
enlarged.

(- and d, head and mouth parts ; all

Fig. 417.

the horns of cattle, although it is really just as abundant on the
flanks, upon the udder, and in other places where it cannot be
readily reached by the animals. The fly seems to confine its at-
tacks to horned cattle, although it has been seen on mules in the
State of New Jersey. Like the stable-fly, it
is a blood-sucker, and both species are often
found on animals at the same time, keeping
them in that state of constant irritation
which prevents their proper feeding and
digesting, and keeps them poor and in no
condition to produce a free flow of milk.
Not only in the fields or pastures are the
cattle annoyed by these insects, but in the
stable as well, so that the animals get no
rest night or day. Eggs are laid in fresh
cow-dung, and before this has an oppor-
tunity to dry under ordinary conditions, the
larvae are full-grown and ready to pupate. It is the immense
number of these insects that makes them dreadful, and when the

Egg of horn-fly. — i,
unhatched, from side;

2, hatched, from front;

3, same, from side, to
show lid-like structure;
all enlarged.

360

AN ECONOMIC ENTOMOLOGY.

Fig. 418.

species first made its appearance in the Eastern United States,
horrible tales were told of the destruction caused among herds
of cattle. As a matter of fact, except for the irritation, it causes
no injury. Much can be done to prevent the increase of this
insect by destroying the breeding-places. In the stable, the stalls
and their surroundings should be kept absolutely clean, and
whitewash should be liberally applied. The manure should be
mixed at once with either kainit or land plaster, which absorbs

the moisture and makes the mass
unfit for the larva, while at the same
time it does not injure its value as a
fertilizer. A boy should be sent
through the pasture every two or
three days with a shovel, and di-
rected to spread out every dropping
in such a way as to cause it to dry
up or wash away readily before the
larvae can complete their develop-
ment. The flies can be kept from
the animals by the use of fish oil
and crude carbolic acid, applied to
those parts not readily reached by
the tail. The proportions of fish
oil and carbolic acid are not im-
portant ; enough of the crude acid
to give a decided odor is all that is necessary, and one appUcation
will usually suffice to protect an animal for five or six days.

Another series of decidedly troublesome flies we find in the
Anthomyiids, whose larvae are frequently root-infesting maggots.
The adults closely resemble the common house-flies, but are usu-
ally somewhat smaller in size and slighter in build. They are
found in fields on the ground, on vegetation of all kinds, and
also commonly enough in our houses on the windows, where they
are usually mistaken for the true house-fly. Recognition of the
species of these flies is a matter of no great importance practi-
cally ; but it may be assumed, where flies resembling the ordinary
household pest in all save size are noticed in any number about
crops subject to infestation by root-maggots, that we have mem-
bers of this Anthomyiid series to deal with. They are often very

Larva of horn-fly, i ;
structural details, 3,4,

THE INSECT ]VORLD.

361

Cabbage-maggot, Phorbia brassica. — a, larva ; b, pupa ;
c, adult ; d, its head ; e, antenna.

injurious to cabbage and cauliflower, as well as to onions, rad-
ishes, turnips, beets, and other root crops, while other species
attack planted seeds

like those of melons ^^^- 4'9-

and even corn. Oc-
casionally, instead of
attacking roots, the
maggots are found
boring in thick or
fleshy leaves, and
then they make
mines or galleries be-
tween the upper and
lower surfaces, often
doing much injury.
Sometimes their hab-
its are more hke
those of the house-
fly, and the larvae are
scavengers, while a
few have been recorded as parasites on other insects. The
group, therefore, is one with diverse habits, but usually to be
looked upon with considerable suspicion. Perhaps the best
known of the root-maggots is the larva of Phorbia brassicce, in-
festing cabbage, cauliflower, and other plants of the same natural
family. Eggs are laid on the ground soon after the plants are
set out in the fields. The larvce make their w^ay into them as
soon as they are hatched, gnawing or rather scraping the tissue,
so as to enable them to absorb the plant juices, for they have no
jaws for mastication. Decay sets in where the insects work, and
this favors their feeding, so in a few days they destroy the tissue
of the plant and stem a little below the surface so completely that
it dies. Later crops are not so much harmed, as a rule, and if
plants can be preserved until they reach a good size, they fre-
quently sustain considerable maggot attack without serious in-
jury. As to the best remedies against this particular insect we
are yet somewhat uncertain. Putting a pad or disk of tarred
paper on the stems of the plants when they are set out has been
found successful in preventing the adult from laying eggs, or the

362 AN ECONOMIC ENTOMOLOGY,

larvae from getting at the desired point, smce they seem to be
unable to live exposed to sunlight. Ground tobacco, kerosene
and sand, plaster, soot, ashes, and other materials placed at the
base of the plants act like the tarred paper as a mechanical pro-
tection, and must be applied before the eggs are laid, else they
will prove ineffective. Bisulphide of carbon injected below the
root system has been used with a considerable degree of success,
the fumes filtering through the soil and killing the insects at
work on the plant without injuring the plant itself An injector
devised for the especial purpose has been made by Mr. J. J,
McGowen, of Ithaca, New York, and perhaps the appHcation of
this substance is the most certain and satisfactory remedy that
has been proposed. It should be used when the soil is moist,
but not water-soaked. There are two or three broods in the
course of the year, according to latitude. The winter is passed
either as a pupa below the surface or as an adult in barns,
houses, etc., and the species is tided over between cultivated
crops by the cruciferous weeds. Hence clean culture and the
prompt removal of all crop remnants are urgently indicated.
Carbolic acid and kerosene, emulsified with soap according to the
formulas elsewhere given, have proved effective as killing agents
when the maggots have begun feeding. Pour about half a pint
around the base of the infested plant, diluting the carbolic acid
emulsion thirty times and the kerosene emulsion twelve times.

Radishes frequently suffer from the attacks of the same
maggots, and they are more difficult to deal with here, because
they puncture the fleshy root and make channels through it in
every direction, safely beyond the reach of any insecticide appli-
cation. It rarely pays to put expensive substances on radishes,
because the margin of profit is too small ; but considerable
benefit may be derived from proper methods of fertilizing, and
the mixture that seems to offer the best chance for success is

Nitrate of soda 700 pounds.

Ground rock 1000 pounds.

Muriate of potash 300 pounds.

Apply soon after the plants are up, or when the leaves are about
an inch long, at the rate of five hundred pounds per acre, and
before or during a rain. The application made at this time seems

THE INSECT WORLD.

l^l

to reach the iiia_oL>ots just when tlu-y are hatchuior, and becomes
effecti\'e for that reason. AppHcd later, when the insects have
already made tlieir way into the radishes, it would be useless.
Here tiie farmer must necessarily make a few observations of his
own to determine the proper time for applying the fertilizer
remedy, and this is not difficult. The flies lay the eggs in little
masses on the surfice of the ground near to the infested plants.
They are white, slender, and cylindrical, nearly one-sixteenth of
an inch in length, and quite visible on close examination. When
these eggs are found generally distributed over the fields the
time to make the insecticide application has arrived, because they
hatch only a few days after they are laid, and the young larvae
must be reached then or not at all. The carbolic acid emulsion
diluted thirty-five times may also be applied with good prospects
of success in killing the maggots, or the ground tobacco may be
used over the rows just as soon as the plants are up.

The onion-maggot, Phorbia ceparian, is, perhaps, next in im-
portance, and its habits are essentially the same as those given
for the cabbage-maggot, — that is, the eggs are laid by the fly
quite early in spring,

next the onion stems or ^'^- 42o-

leaves at the surface of
the ground, and prefer-
ably in young onion
beds. In the latitude of
New Jersey this occurs
in May, but the date va-
ries somewhat accord-
ing to the season and to
the time at which these
plants are started. The
larvee w^ork their way
into the bulb at once
and begin their scraping
and gnawing, leading to

the rapid decay and death of the plant. Matters are even more
serious here than in the cabbage, because where a bulb has been
started in decay, it usually continues, even if the maggots are de-
stroyed, and in the case of scullions, they become unmarketable.

The onion-maggot. — Larva, pupa, adult, and section
of an infested onion.

364 A^ ECONOMIC ENTOMOLOGY.

The maggots attain their growth about the end of May or early
in June, and before the middle of that month a second brood of
flies may be found in the fields. This second brood is often
much the most injurious, and quite frequently it attacks seedling
onions, ruining entire beds. The older plants, if they have
reached this date unharmed, are usually safe for the year. Exactly
how many broods there are has not been accurately ascertained,
and probably the number varies somewhat according to latitude.
We do know that the insects pass the winter partly in the pupa
stage in the ground, and partly as adults in barns, farm-houses,
and other sheltered localities. Many measures to prevent injury
have been proposed, none with any marked success, except those
here mentioned. The most promising is sand soaked in kerosene,
one cupful to a pail of dry sand, and placed at the base of the
onion plants along the rows. This prevents egg-laying by the
fly, kills any young larvae that may attempt to work through it,
and seems to have been quite satisfactory where tested ; but it is
obviously not a suitable measure for application on a large scale.
In New Jersey tons of onion seed and sets are raised annually,
and the following practice has been found uniformly successful.
Keep a close watch for the first signs of maggots ; carefully lift
out and destroy all infested plants that have wilted down so far
that they cannot survive, and so kill the more advanced maggots.
Turn away the earth from the rows with a hand-plough so as to
expose the root system in part, then apply broadcast about six
hundred pounds of kainit and two hundred pounds of nitrate of
soda per acre ; turn back the earth to the plants, and this will put
a period to the injury. The application is best made just before
or during a rain, or immediately after a shower that has wet
down pretty thoroughly. The object is to get the salty fertilizers
dissolved rapidly and brought into direct contact with the roots
of the plant, and, of course, with the insects as well. This
method has proved entirely satisfactory in New Jersey, and on
light lands it will probably act equally well in other localities ;
but it has never been tested on heavy land, and the action may
not be entirely the same. The application of the fertilizer has the
advantage of imparting additional vigor to the plant, and stimu-
lates it to overcome such injury as may have been already caused.
It is a good plan always and under any circumstances to care-

THE IXSECT WORLD. 365

fully take out and destroy plants that have wilted down beyond
recovery, because in this way the maggots are destroyed or pre-
vented from coming to maturity.

Other root-maggots may be treated on the lines just laid down,
and nothing can be gained by multiplying instances. Too little
is known of most of the leaf-miners to give any general directions
concerning the methods which may be used to check them ; but
one remedy, or rather preventive measure, is always useful. A
crop of infested leaves should always be disposed of as soon as
possible. For instance, if beet leaves are attacked at the time
the roots are harvested, they should be at once destroyed, and
with them the insects yet in the plants. In this way much can
be done to lessen their number for the ensuing season. Direct
applications for leaf-miners are unsatisfactory, because of the
difficulty of reaching them.

The remainder of the Muscid flies differ from all the preceding
in that they have no perceptible winglct or alulct just below the
anterior wings. If the " blow-fly" or the " house-fly" be exam-
ined, it will be found that just behind the base of the large wings
there is a little flap resembling in appearance a minute wing.
This is called the " winglet" or "alulet," and it is more or less
obvious in all the Muscids of which we have heretofore spoken.
It is absent in all the other groups, and serves to divide this
large family into two fairly distinct series.

We find it absent in a large series of flies belonging to the
Trypetids and Ortalids, which are usually small in size, often
metallic in color, and with the wings frequently banded or mot-
tled. Some of the species have the habit of strutting up and
down with the wings elevated and spread out, and this has given
them the name "peacock flies." They are gracefully built in
most instances, and are noticeable by keeping the wings in con-
stant motion even when feeding or walking about on flowers,
where they are most frequently found. They fly rather slowly,
and, as a rule, are easily captured. The abdomen of the female
frequently ends in an extensile, horny-tipped ovipositor, by
means of which the eggs are laid in the plant tissue in which the
larvae feed. Most of the members of the series feed in plant
tissue of some kind, either in leaves, in stems, or in fruits, and a
number of them are gall-makers. The most notable instance of

366

AN ECONOMIC ENTOMOLOGY.

the latter type in the Eastern United States is seen in the round
swelUngs so frequently found on the stems of golden-rod. A
number of species are locally injurious to fruits, but there seems
to be no one injurious form generally distributed throughout this
country. In the Northern and Eastern United States the so-
called " apple" -maggot, Trypcta pomonella, is the only one
causing trouble, the fly laying its eggs in the tissue of the apple by

Fig. 421.

Trypeta pomonclla, parent of the apple-maggot.

piercing the skin with its horny ovipositor. The little maggots
channel the fruit in every direction, causing it to rot or become
unsalable. When full-grown they pupate below the surface of
the ground, or even among rubbish on the surface, or in crevices.
Indeed, they are not at all particular, and transform wherever
they can find an opportunity to do so, including the barrels,
boxes, or bins in which infested apples have been kept. None of
these fruit flies can be reached by insecticides, nor is there any
fair chance of reaching the adults, and the only method that
is effectual is the prompt removal and destruction of infested

THE INSECT WORLD.

367

fruit. Windfalls should be picked up constantly and destroyed
at once. Summer varieties, especially sweet types, are most in-
fested, and these should be sent to market at once if the apples
are marketable, or if they are not, they should be disposed of in
some eifective manner to prevent the maturing of the flies. They
seem to be more common in the Northeastern States, extending
southward only to Central New Jersey. South of this point they
seem to be unknown, or so rare as not to be injurious.

Probably every one has noticed in the fall, at cider making, or
when grapes are pressed for wine, or, in fact, whenever there is
an accumulation of fruit of any kind in which fermentation or
decay has started in ever so slight a degree, that swarms of little,
yellowish flies make their appearance, easily distinguished by
the bright coral-red color of the eyes. No specimens may have
been noticed previously ; but just as soon as the material at-
tracting them makes its appearance, swarms are seen coming
from no one knows where. They lay their eggs in the ferment-
ing or decaying mass,
and a few hours after-
wards there will be an
abundance of small,
white, wriggling mag-
gots. These become
mature in three or four
days, and after another
day or two in the pupa
state, they develop into
adult "pomace flies,"
species of Drosophila. The insects are sometimes annoying
and a little troublesome, but scarcely injurious, and it is only
because they are so common and occur so suddenly in large
numbers that they are mentioned here. Little attention is paid
to the larvae either in wine or cider making, because they are
thrown out in the process of fermentation, and do not in any way
affect the quality of the resulting product.

To this same family belong the " skippers" M^hich are found in
cheese and sometimes in other kinds of provisions. The term
is derived from the habits of the larvte, which move about by a
series of little jumps somewhat resembling those of the larvae

A pomace fly and its larva, Drosophila species;
enlarged.

y

368

ajV economic entomology.

Piophila casci, parent of '
etc.

' skippers" in cheese,

of the Cecidomyida:. They produce a Uttle black fly, Piophila
casei, similar to the house-fly in appearance, but much smaller,
and the only way to protect provisions is to keep them con-
stantly covered. They sometimes become an intolerable nuisance
in smoke-houses, attacking ham, bacon, and the like during the

process of smoking, or be-
FiG. 423. fore they can be cased, and

the value of the provision
is frequently impaired by
the development of these
maggots. Where a house
is once thoroughly in-
fested, the flies are found
in swarms everywhere,
ready to attack the meats
as soon as there is the
least opportunity. Under
such circumstances thor-
ough measures are neces-
sary to get rid of them. In the first place, windows should be
closely screened to prevent their entry from outside ; the walls
should be whitewashed frequently, so as to keep all crevices
filled up ; the floors should be kept clean, and should be as solid
and smooth as possible, to prevent the development of maggots
in crevices filled with greasy substances. The flies can be killed
by fumigating with tobacco or pyrethrum, and this should be
done by closing up the rooms tightly in the evening after work
is done, or on a Sunday or other day when work ceases, and a
sufficient quantity of either tobacco or pyrethrum should be
burnt on live coals to comj)letely fill all parts of the rooms. They
should be left tightly closed anywhere from eight to twenty-four
hours, and at the end of this time the flies will have been de-
stroyed, but the maggots will not, and it will be necessary to
repeat this operation two or three times, at intervals of (at most)
a week, to destroy the flies as fast as they hatch, and before
they have an opportunity to lay their eggs. In some cases bi-
sulphide of carbon may be used to fumigate ; but this must be
done when there is no fire on the premises, and the house
should be left closed twelve hours at least, and should then

THE lA'SECT WORLD.

369

A louse-fly, Olfersia species.

be aired until no trace of odor remains before fires are again
introduced.

The last family in the Diptcra to which we need call attention
are the " lousc-fiics," or Hippoboscidcc, frequently separated as
a sub-order under the term Piipipara, the latter being applied
because of the curious method of reproduction. The flies are
parasites, living largely upon birds, but sometimes upon animals,
and the eg^ not only

develops within the Fig. 424.

body of the female, but
the larva becomes nearly
full-grown in the same
position, and practically
attains the pupa state
before it is extruded.
In these species the ab-
domen is somewhat flat-
tened and oval in form,
of a thick, leathery con-
sistency, with a very

large anal opening, and from the circumstances of the case only
one larva at a time is produced, so that the flies produce young
only at considerable intervals. The whole body is depressed or
flattened, and birds of prey are most usually affected. It is rare
to find a hawk, eagle, or owl upon which several specimens of
these peculiar flies cannot be found. They
move about rapidly, and their first impulse is
always to seek shelter when driven from their
original host. Thus, in handling hawks that
have just been shot, the flies frequently dart
upon the hunter and make their way under his
clothing and to his body.

A few species are wingless, and among them
is the so-called "sheep-tick," Melophagus
ovimis, which is usually looked upon as a
louse, and resembles one in the prominent
proboscis, the lack of wings, and the strongly developed legs,
on which the claws are very prominent. This "sheep-tick" is
the only troublesome species, and it can best be kept in check

24

Fig. 425.

Sheep-ticK, Melopha-
gus ovinus.

37°

AN ECONOMIC ENTOMOLOGY.

by frequent dipping, using a carbolated dip which readily de-
stroys the insect. Thorough washing after shearing will usually
clear the animals completely, and if the entire herd be once
freed, it will remain so until infested animals are introduced.
The parasites are able to move from one to the other only when
the animals are herded close together.

Yet more louse-like in appearance is the little whitish creature,
Braula c<zca, found upon the honey-bee as a parasite ; but it

Fig. 426.

Bee-louse, Braula ccrca, and its larva ; much enlarged.

seems to be rather rare, and, in our country at least, does not
assume the dimensions of a serious pest.

CHAPTER IX.

THE HYMENOPTERA.

Bees, Wasps, A)its, Smv-flies, etc.

There is no order of greater interest than this, containing as
it does the bees, wasps, and ants, the most useful as well as the
most intelligent of the insects. By treating them last, the inten-
tion is not to suggest that they are lowest, but rather that they
are the culminating point in the development of the class. Here
we find social organizations not unlike some of our own systems
of government, but more complete and running much more

THE INSECT WORLD.

371

smoothly. We find division of labor carried to an extreme ;
combination for special purposes ; skill and energy in the prepa-
ration of homes ; and, finally, we discover the helpless young
cared for by parents or nurses. It is only in the Hymc7ioptera
among insects that we find true babies, — that is, young that must
be fed and tended until they are ready to assume the adult form.
Nowhere else do we find larva? fed on anything but simple,
natural food ; but by many bees a mixture is prepared and fed ;
not honey or pollen alone, but a combination of the two in defi-
nite proportions is given, and these proportions vary with the
sex of the larxa.

Members of the order Hymenoptera may always be distinguished
by the presence of four transparent wings, the anterior always the
larger, the secondaries frequently very small. They are not cov-
ered with scales, but are often set with small hair, and the cells
and veins are comparatively few in number ; never netted as in the
Neuroptej'a. The mouth parts are mandibulate, or formed for
biting, but in many of the families there is also developed a large
tongue-like structure which serves for lapping, none of the Hy-
menoptera being strictly haustellate, or sucking insects. The
metamorphosis is complete.

Taken as a whole, the order contains beneficial insects ; but as
there is no rule without exceptions, so we find here also one
series the species of which are vegetable feeders. These are in-
cluded in the families Teiithredinidce and Urocendce, the "saw-
flies" and "horn-tails."

The term "saw-flies" is used to indicate a series of species
peculiar by the structure of the ovipositor, which is made up of a
number of parallel blades toothed at the edge, by means of which
the insects are enabled to cut pockets or slits in leaves or other
vegetable tissues to receive the eggs. They are further peculiar
by having the abdomen sessile, or joined for its full width to the
base of the thorax, and the wings are rather larger in proportion
to the body than in other groups. The larvae are caterpillar-like
in appearance, but they always have at least one more pair of
prolegs than any caterpillar, — six pairs or more, of which one
pair is anal, — which renders them easily distinguishable. They
are often more or less slimy in appearance and to the touch, and
perhaps a majority have the habit of coiling the posterior por-

372

AN ECONOMIC ENTOMOLOGY.

Fig. 428.

tion of the body around the edge of the leaf or twig while feed-
ing. This is quite a characteristic peculiarity, and there is rarely
excuse for mistaking the larva of a saw-fly for that of a Lepidop-
teron, even without counting the prolegs. Many of these larva?
are injurious to cultivated plants, and some of them are known to
farmers as ' ' slugs' ' or " worms ;' ' for instance, we have the
"currant- worm," the "grape-slug," the "rose-slug," and the
"pear-slug." When these larvae are full-grown they form thin,
tough, parchment-like cocoons, in which they change to pupae,
sometimes on the plant on which they feed, sometimes a little
below the surface of the ground.

Perhaps none of the members of this family are better known
than the "currant-worm," or "slug," Nematus ribesii, which is
an imported insect, and annually does great injury where its food
plant is raised on a large scale. The flies, which are easily dis-
tinguishable by a rather deep yellow body, may be seen sitting
upon the foliage, or flying about heavily as
soon as the leaves of the currants are toler-
ably well developed in spring, and we may,
even at that time, find on the under sides,
arranged along the veins, series of little
white eggs laid by them. The larvae soon
make their appearance and feed ravenously,
frequently stripping a bush completely in
the course of a few days. I have seen rows
of currants covering an acre or more almost
entirely devoid of leaves and the fruit hang-
ing to bare twigs. There are two or three
broods in the course of a season, depending
upon latitude, the latter rarely as abundant
as the first and second, and practically not
nearly so destructive. The larva is green,
dotted with black, and nearly an inch in
length.

On pears we frequently note a very dark green slug, the larva
of Eriocampa cerasi, which is more or less slimy to the touch.
On young trees this sometimes does much injury by scraping
the upper side of the foliage until it dries and withers, falling to
the ground in midsummer.

Pear-slug, larva of Erio
canipa cerasi.

Fig. 427.

Fig. 431.

Fig. 427. currant-worm.— a, a, male and female adult ; b, larvae; c, pupa -n (d) cocoon;
e, eggs. Fig. 431, Phyllu-cus JiavivetUris.—a, female adult ; b, c, male and female abdomen ;
d, spur of anterior tibia.

373

374 A^ ECONOMIC ENTOMOLOGY.

On grapes there are often black-dotted slugs, the larvse of
Blennocampa pygmcBa, that do some injury ; and on roses almost
every grower has been annoyed by numer-
■ ous green slugs, the larvae of Monostegia

ros(£, which make their appearance early in
the season.

Raspberries are sometimes severely in-
jured by little spiny slugs, the larvae of
Monophadtius rubi, that appear in June or
early July, first eating round holes in the
leaves, but eventually, when they become
Grape-slug, larva of y?/<'«- numerous cuough, taking the foliage com-

nocampa pygmcra. ^ °. ^

pletely. Many other cultivated plants, in-
cluding the strawberry, are attacked by these saw-fly larvae ; but
their habits are very similar, and the remedies to be adopted
against them are also very much the same.

The largest of our American species, Cimbex aviericana, is
found on willow, sometimes in considerable number, as a pow-
dery, whitish larva an inch and a half in length, with a broad
dark stripe on its back.

Experience has shown that all these species are very suscep-
tible to the influence of white hellebore, and that even a small
quantity is quickly fatal. Infested plants can, therefore, be
cleared in a few hours by a thorough drenching with a decoction
of white hellebore, used at the rate of one ounce in one gallon of
water ; or the plants may be dusted with the powder, undiluted
or mixed with several times its own bulk of cheap flour. Any
stomach poison — e.g. , the arsenites or tobacco — ^will answer as
well as hellebore, while on the slimy types even fine road-dust
will quickly choke them to death. Air-slaked or dry hydrate of
lime burns through them in less than an hour when carefully ap-
plied. These insects are so easily killed that it is the fault of the
farmer himself if he suffers injury.

The "horn-tails" resemble the "saw-flies" in a way, but the
character of the ovipositor is different and rather more like an
auger or borer than hke a saw. So, too, the species are, as a
rule, internal feeders instead of eating openly upon the foliage.
The larvae are usually slender, white or nearly so, and in-
fest plants ranging from the stems of wheat to the trunks of

THE INSECT WORLD.

375

trees. , Some forms live in blackberry and raspberry canes,
others in grasses ; I have taken a species from alder, and in
fact a very large number of plants are infested by these boring
Hymenoptcra. The largest of our species is the ' ' pigeon Tre-
mex," T. columba, the larva of which attacks quite a consider-

FiG. 430.

Pigeon Tretnex, T. columba. — a, larva, with young larva of Thalessa fastened to its
side ; b, its head ; c, d, female and male pupae ; e, female.

able variety of trees, including maple, elm, hickory, and beech,
and bores into the solid wood, usually when the tree is beginning
to die, or is even dead, but not decayed.

Dealing with these insects is always rather a difficult matter,
because we have no means of getting into the infested plants with
insecticides. We are again reduced to farm practice, and must
arrange our methods of cultivation in such a way as to reach and
destroy the insects by depriving them of food. Thus, with the
Phylloecus infesting blackberry, if the canes are topped about
midsummer, or a little before, the larvae never mature, because

376

AN ECONOMIC ENTOMOLOGY.

Fig. 432.

the wood dries, becomes unsuitable for food, and, as the insect is
incapable of travelling, it starves to death.

In the case of Cephus pygmcsiis, the insects boring in wheat,
they spend the winter either low down in the infested stalk — i.e.,

in the stubble — or in the soil just
below the surface, in either the
larval or pupal condition. The
proper remedy is to burn the
stubble as soon after harvest as
possible, or to plough it under
deeply. This destroys the in-
sects and results in preventing
injury the year following. We
have no means of reaching the
larva while it is actually working
in the stem of the plant. The
remedy is radical, and were it
universally resorted to, would
need to be applied only at inter-
vals of several years.

The "gall-flies," belonging to
the family Cyriipidcs, are curi-
ous creatures. They resemble
minute wasps in form, and gen-
erally have a very short, chunky
body, which is often compressed
and joined to the abdomen by a very slender petiole or stalk,
in sharp contrast to the species heretofore written of. These
gall-flies are mostly true parasites on plants. They derive their
common name from the fact that they produce swellings, protu-
berances, or "galls" of great variety on vegetable tissues ; some-
times on leaves, on twigs, on trunks, or even on roots ; and
perhaps, of all others, the oak is the favorite of the insects of
this family, bearing the greatest variety of galls on all its parts.
I say these insects are mostly plant parasites, and intend to ex-
press by this that they do not actually eat the infested vegetable
tissue. The irritation caused by the larva induces an abnormal
growth in the part of the plant infested, and in a cell in this
growth it has its home. Here the insect reaches maturity with-

Cephus pygmo'us, wheat-stem saw-fly.
— a, outline of larva, natural size ; b,
larva enlarged; c, larva in wheat stalk,
natural size; <?, adult female; y^ female
parasite, enlarged.

THE nVSECT WORLD.

377

out devouring any part of its vegetable envelope, changes to a
pupa, and emerges from the gall, leaving it intact, except for
the hole through which it emerged. It seems, therefore, as if
certain abnormal plant ex-
udations secreted in the Fig. 433.
gall form the actual food
of the larva, and it is a
curious and interesting fact
that the same species in-
variably produces in the
same place the same kind
of gall. In other words,
the appearance of the gall
is an unfailing index for
the special student to the

species that made it. Many interesting problems are connected
with the study of these gall-flies ; for instance, in some species
both sexes are present early in the season, but in the second or
midsummer brood females alone make their appearance. The

Fig. 434.

An oak gall-fly.

Gall made by the larva of Cynips q. spongifica.—a, larva in its cell ; b, point
of exit of adult.

progeny of this female form, which may or may not resemble
the spring form, in turn produces males as well as females. Of
other species no males are yet known, and, so far as we have

378

AN ECONOMIC ENTOMOLOGY.

any evidence at present, there is a continuous breeding by female
individuals only.

There are only a very few injurious species among these gall-
flies. Occasionally we find on blackberry stems an irregular,

warty swelling, and if
Fi<^- 435- this be cut into, it will

be found full of cells
occupied by these little
Cynipid larvae. This
kind of gall is known
as " multicellular," be-
cause inhabited by nu-
m e r o u s specimens.
Similar galls are found
on the roots of rose
and plants of the same
natural family, and in
a few other cases cul-
tivated plants become
subject to gall growths.
As a matter of fact
these galls are scarcely
injurious, because in
most cases the plant
continues growing be-
yond them, or even if
a shoot is lost, perma-
nent injury is rarely
done. Certain species
of oak-galls produce a
black stain, and these
were at one time al-
most universally employed in making an ink of remarkable per-
manence. Even yet the law in some States requires for certain
records an ink of which oak-galls is one of the ingredients.

It is a small step from parasitism upon vegetation to parasit-
ism upon animals, and hence it is not surprising to find that some
species of this family are parasitic on other insects. The differ-
ences between these forms and the true gall-makers are not easily

a, Pithy
7iebulosus ,
pupa.

gall on blackberry, made by Diaslrophus
b, section to show cells; c, larva; rf,

THE hXSECT WORLD.

379

pointed out, since the insects are usually small in size ; indeed, it
is a matter of little importance to the farmer, because in any case
he can look uj)on these gall-wasps with indifference, and without
much fear of possible injury to himself.

There is a very large series of parasitic Hymenoptera, and 't
contains a number of families, nearly all the species of which are
beneficial. To the practised eye a doubt rarely exists as to
whether an insect is parasitic or not ; but
that the student may be able to decide
this matter for himself if he chooses, it
may be pointed out that the trochanter,
the little segment between the coxa and
femur of the leg, is rather peculiarly de-
veloped here. It is normally composed
of one joint only in all the bees, wasps, and
ants, whatever their size or appearance,
but it is two-jointed in all the parasites. «- two-jointed trochanter

, . , , ., of parasitic Hvmcnoplera ;

1 his character can be easily seen on large t, normal structure,
specimens with or without a lens, but on

minute species it becomes more difficult ; and, after all, in most
cases the farmer is justified in assuming that most of the minute
wasp-like creatures that he notices are parasites and beneficial.

One feature characteristic of a great number of species is an
external ovipositor, or egg-laying tube, and this may vary from
a scarcely visible projection to an enormously developed hair-
like appendage five to six or even more inches in length.

There may be frequently seen on the trunks of various trees a
quite large ichneumon, a Thalessa, yellow or black in color ac-
cording to the species, which has its long, bristle-like ovipositor
forced deep into the wood, and so firmly fixed, occasionally, that
it is unable to withdraw it, and perishes miserably. Wherever
this occurs the trees will be found infested by borers, and all but
universally this ichneumon is accused of being the parent of the
larva that produces the injury. The circumstantial evidence is
all against it ; but we really have here a beneficial species which
is after the wood-boring larva of the "pigeon Tremex." The
insects seem able to recognize an infested tree, and pierce the
trunk until the ovipositor reaches one of the burrows of the wood-
feeding larva. In this an egg is laid, and the larval parasite,

Fig. 437.

Long-tailed ichneumon, Thalessa lunator. — a, larva; b, head of same; c, pupa; d, tip of
pupal ovipositor; e, female adult; /, tip of abdomen, seen from the side; g, male adult ;
h, tip of abdomen.
380

THE INSECT WORLD.

381

when hatched, crawls along the burrow until it comes into contact
with its host. It then punctures the skin and remains fixed to
the outside, sucking the juices and gradually killing the borer.

Fig. 438.

Pimpla conquisitor. — a, larva ; c, pupa; rf, adult; other references are to structural

details.

By no means all of our " ichneumons," even of those belong-
ing to the family Ichuumonidcs, have external ovipositors ; yet
there is a distinctive character in their appearance which is easily
recognized but hard to de-
scribe. The species belong- ^''^- 439-
ing to the typical genus Ich-
7ieumon have rather long,
slender forms, with flattened
abdomen and no external
ovipositor. They are often
gaudily colored, the antennae
are frequently banded with
yellow, and many are metallic
blue or green. The species
are usually parasites on cater-
pillars. One of the largest
and most frequently noted species is that which infests the larvae
of the common "swallow-tail" butterflies. It is orange-yellow
in color, with smoky-black wings, the body nearly an inch in

Tragus excsorius on a chrysalis of Papilio,
from which it has emerged.

382

AN ECONOMIC ENTOMOLOGY.

length, and the wings expanding fully an inch and a quarter or
even more. This makes the species easily recognizable, and it
will serve very fairly as a type of this particular branch of the
family. Species of this size usually lay only a single o.g'g in the
host, and in the case of the " swallow-tail," the caterpillar retains
strength enough to change to a chrysalis ; but from this chrysalis
there emerges through an ugly hole in the side the Tragus exe-
son'us, which has just been described. Frequently, however, in
smaller species, a considerable number of parasitic larvae develop
in one caterpillar.

Of quite a different type, as compared with those just described,
are the species of Ophion. These are large or very large
creatures, black or honey-yellow in color, and the bodies are

transversely flattened and
Fig. 440. squarely cut off at the pos-

terior extremity. They are
thus blade-like in shape, and
the ovipositor rests concealed
in a groove in the squarely
cut off end segment. Though
these insects are not stinging
Hymenoptera, strictly speak-
ing, yet the ovipositor is so
short and sharp that the in-
sects make use of it as a
means of defence. They
should be carefully handled,
therefore ; though the sting,
if " hot" for a few moments,
seems not to be so poisonous
as that of the bees and wasps.
In the family BraconidcE
the species are smaller, as a
rule, — sometimes very small
indeed, — and all are parasites. The difference between the pre-
vious and the present family is in the venation, and is not easily
made out, except by the special student ; nor from a practical
stand-point is the matter an important one. It is among the
members of this family that we find many of the minute creatures

Long-tailed Ophion, Ophwn tnaciinum, and
larva.

PROPEBTY

ur

THE INSECT ifD^LD. 383

that infest aphids. If, at any time during the summer, a leaf
badly infested with plant-lice be examined, there will be usually
found a few specimens that seem abnormally swollen and livid
gray in color rather than green or yellow. Such specimens are
parasitized, and if they be removed to a closed vessel, there will
be found in it, in a few days, minute blackish or brown wasp-like
creatures, and on each of the infested plant-lice will be seen a little
round hole, which shows where the insect emerged. They are
usually examples of minute Braconids, and are the most im-
portant of those natural checks that prevent the increase of plant-
lice above a certain point. Unfortunately, that point does not
coincide with the limit at which the insects become injurious to
the farmer ; hence, though the parasites accomplish their pur-
pose, they do not, therefore, confer any direct benefit upon him.
At almost all periods during the season, but especially late in
summer or fall, caterpillars may be seen, bearing upon their
backs and sides white or yellowish, egg-shaped bodies. These
are often supposed to be the eggs of the caterpillars, but as a
matter of fact they are cocoons of Microgaster or Apayiteles,
little parasites belonging to this family ; and if the caterpillar be
confined for a few days it will be noticed that from the tips of
each of these egg-shaped bodies a little circular lid is lifted off
and a Httle wasp emerges. If, late in summer, a number of the
large sphinx caterpillars infesting potato or grape-vines are
watched when they yet show no signs of infestation, one may fre-
quently see the little larvae boring their
way through the skin, wriggling until '^'•

they have emerged for more than half
their length, and it is then easy to
watch the formation of the small silken

,-p,, ... , Sphinx larva covered with iSIi-

cocoons. The caterpillar soon becomes crogaster zo<,oor.^.

an odd-looking sight, with anywhere

from a dozen to fifty or even a hundred of these little maggots,
all engaged in spinning cocoons, projecting from it in every di-
rection. The egg-like cocoons are attached merely by a Httle
point, so that they may be easily removed. But the caterpillar
has been drained of its strength and of the substance for the for-
mation of the future butterfly : it collapses and dies, unable to
complete its transformation to the pupal stage.

384 AN ECONOMIC ENTOMOLOGY.

Most of these parasites have the disadvantage of not influ-
encing in the least the amount of injury done by the host ; they
simply prevent it from changing to an adult. It often happens
that spinning caterpillars even complete their cocoon, and in this
we find the mass of parasitic cocoons instead of the Lepidopter-
ous pupa. On the other hand, some of them complete their

Fig. 442.

Apcuiteles species. — Little mass of cocoons on leaf, replacing an infested larva; a
single cocoon below, from which adult has issued ; much enlarged.

development and kill the caterpillar before it is much more than
half-grown. Many of these cocoon-forming species belong to
the genus Microgaster, and they are typical of a very large
series in the family. The plant-lice-infesting forms frequently
belong to the genus Aphidius. As in the previous family, many
of these insects have an external ovipositor.

While the preceding series of parasites contain a very fair pro-
portion of large species, the next family, Chalcididce^ contains

THE INSECT WORLD. 385

very i&\\, except small forms, which are quite usually metallic

black, bronze, or green. The wings are without venation, except

for a strong vein running parallel to the costal margin, but not

reaching quite to the tip, and

the antennae are geniculated Fig. 443.

or abruptly bent at the end

of the long first joint. Few

of these have the ovipositor

visible, and usually it lies in

a groove on the under side

of the tip of the abdomen,

issuing before the apex. These

Chalcidid flies are exceedingly

. . Apheltnus ntvMaspidis, parasite on scale

numerous, and are parasitic on insects ; much enlarged.

a great variety of other insects.

They are rather more robust in build than the other small para-
sites, and this fact, with their usually brilliant metallic coloration,
is a tolerably good guide to the family, of which the species in-
festing the common cabbage butterfly may serve as a good
example. If, early in the spring, a large number of chrysalids
of the cabbage butterfly be collected, — which can be easily done
along the fences bordering last year's cabbage-field, — it will be
found that some of them have a rather warm gray color and
move the joints of the abdomen freely, evidently showing life.
Others will have a peculiar, dead, straw-yellow color, and the
abdomen is brittle and will break rather than move. If it does
break, the interior of the chrysalis will be found completely filled
with little, greenish-gray, maggot-like larvae, in which the seg-
ments are well marked and a little darker in color. If such
infested chrysalids be removed to a warm room and kept in a
covered vessel, there will emerge in due time dozens of Ptero-
mains pKpariun, a greenish-bronze Chalcidid, instead of the
common white cabbage butterfly.

Though these insects are minute, being scarcely one-eighth of
an inch in length, yet they are giants compared with others
which live in scales and even in the eggs of other insects. Very
frequently such Chalcidids are bred from galls, and they are here
either parasitic upon the actual gall-maker, or they may live in
the abnormal tissue produced by the Cynipid larvae. We find

25

386

AN ECONOMIC ENTOMOLOGY.

the little fellows everywhere, infesting almost all kinds of insects,
and undoubtedly they do much to prevent the increase of injuri-
ous species. Especially is this true of those ovipositing in eggs
of other forms, for they are then "nipped in the bud," so to
speak. Their work in the destruction of scale insects is also of
great importance, and frequently we find on a scale-infested tree
a large proportion with little round holes, showing where a para-

FiG. 445.

Fig. 444.

Trichogramma pretiosa, a parasite in insect eggs ;
dot may represent natural size.

Female Isosoma oviposit-
ing in stem of wheat.

site has emerged. It is a pity that in a family so generally useful
we should find, exceptionally, some injurious species ; but there
is no doubt that members of the genus Isosoma lay their eggs in
the stems of grasses, including wheat, and the larvae, working as
they do in the joints, have received the name "joint-worms."
The stem hardens where the larva punctures it, and this inter-
feres with the nourishment of the plant above that point, les-
sening or entirely preventing the formation or maturing of the
grain. There is but a single annual brood of these insects, and
the winter is passed in the straw, from which the adults emerge
in spring. In localities where this insect is sufficiently abundant
to make it necessary to use remedial measures, the utilization of

THE IXSECT WORLD.

387

the straw during the winter will check injury to a j^reat extent.
It is certain that some near allies of Isosoma and perhaps some
other genera of Chalcidids are, at least in jjart, vegetarians ;
but, so far as I am aware, none other has proved in any true
sense of the word injurious to cultivated crops. Hence, although,
especially in the central and western parts of the United States,

l'"iG. 446.

Isosoma tiitici. — a, b, larva ; /, atlult female ; .c fore-wing : h, hind wing ; other letters
are structural details.

the "joint-worm" may do some damage, yet it is so easily con-
trolled that it scarcely affects the value of the family as a whole.

The smallest of all our parasitic insects belong to the family
Proctotrypidce , and even the largest of them would be ordinarily
considered as small insects. Among them we find the greatest
number of ^^^ parasites. As compared with the Chalcidids,
these insects are rarely metallic in color, usually black or brown,
sometimes yellow, and much more slender in build ; the body longer
in proportion to the thickness. Their habits may be said to be in
general like those of the other parasites, and they are not easily
distinguished from them, except by the special student ; but they
rarely have the geniculated antennae described for the Chalcidids.
None of these Proctotrypids are injurious, so far as we know, or
feed on vegetable matter, though sojne are found in galls, appar-
ently parasitic upon the original gall-maker.

Taken as a whole, the parasitic Hymenoptera belonging to

388 AN ECO XO MIC ENTOMOLOGY.

the various families heretofore mentioned constitute one of
nature's means of keeping within bounds the insects of other
orders, and, indeed, the various parasites themselves. Not only
are the little creatures parasites upon almost all other insects,
but as a matter of fact they are parasitic even upon each other,
or hyperparasitic, so that it is a clear case of "dog eat dog."

Fig. 447-

Ceiaphron triticiim, parasitic in wheat plant-louse.

They undoubtedly check injurious species, but also each other ;
in this way preserving a balance from year to year which keeps
all the forms at about the same relative level. Of course the
" hyperparasites, " as the forms infesting the other parasitic
species are termed, are distinctly injurious from the agriculturist's
stand-point ; perhaps even more so than the forms actually feeding
on vegetation.

The question of making economic use of parasites belonging
to this order has been frequently discussed, but no practical
results have yet been obtained. Occasionally several species
attack a single host, and yet, withal, they seem to produce no
effect upon it in the long run. Even though we may breed out
of a lot of caterpillars more parasites than butterflies or moths, in
the season following the caterpillars will be just as abundant as
they were the year before. Just where the checks to parasite

THE INSECT WORLD.

589

increase come in is not entirely clear in all cases. Take, for
instance, the cabbage butterfly already spoken of. I have, in
collecting" chrysalids in spring, found scarcely one in twenty that
was living, and from which I obtained a butterfly. All the others
produced parasites, chiefly the little Chalcidid already spoken of:
hundreds of them for every butterfly ! It would seem, then, as
if there were parasites enough here to attack every caterpillar
that hatched from the eggs of this first brood ; yet somehow
they seem to be almost entirely free, and the butterflies increase
normally until after midsummer. It seems almost impossible, in
fact, to get a parasitized larva until August or September, and not
until we get the last brood of caterpillars do the parasites seem to
resume activity, after all the injury has been done to the cabbage
crop. Perhaps ninety per cent, of all the caterpillars will be
found infested at this time, and a mere fragment of the brood
comes to maturity the following spring.

We are unfamiliar with the complete life history of most of
these little species, and, indeed, a great many yet remain to be
described. It would be rash to say that we can never use them
for our own purpose, — that is, in checking injurious species ; but
if so, it is certain that we must know very much more about
them than we do at present.

A very curious creature sometimes found flying through open
woods is the Pelecinus polyturator, for which the family Peleciii-
idcE has been established. The female is remarkable for the length
of its slender abdo-
men, each of the joints Fig. 448.
being almost as long
as the head and body,
and the entire insect
is sometimes nearly
four inches in length,
the abdomen alone
measuring more than
three. The insect is
so very odd and so
often noticed that it

is mentioned here to answer a frequently asked question as to
its character. It is not at all rare in some localities, but its habits

Pehcinus polyturator, male and female.

39°

AN ECONOMIC ENTOMOLOGY.

are yet unknown to us. It is believed to be parasitic, but upon
what sorts of species no one has yet discovered.

The remainder of the order has been roughly classed as
Aculeate, or " stinging" forms, the majority of the species being
provided with an ovipositor modified into a sting like that of the
bee, having connected with it a more or less well-developed
poison-sac. From the fact that the sting is a modified ovipos-
itor, or egg-laying tube, it follows that it can be found in the
female only ; hence the males of bees and wasps of all kinds
have not the power of stinging, and may be safely handled. The
use of the sting varies in the different families, and this subject
will be further spoken of

One little group is separated off under the title " Tubulifera,"
and contains the single family Chrysididce, bees of a brilliant
metallic blue and green, deeply punctured or pitted, and, as a
whole, of rather robust build. They are
iG. 44Q. among the most beautiful of all the Hy-

inenoptera, are of fair size, and are peculiar
in the structure of the abdomen, which is
telescopic. From three to five segments
only are visible, the others being re-
tracted, but capable of a tube-like exten-
sion, at the end of which the minute sting
is situated. They have been called
"cuckoo-bees" from their habit of laying eggs in the nests of
other solitary bees and wasps. The larva is supposed to hatch
before the true owner of the food supply, and to devour the
store, leaving the other hapless baby to starve to death. Eco-
nomically, the species are of no importance, save as they form a
check to the increase of certain other bees and wasps.

Few insects are better known to the average observer than the
ants that are found everywhere : in our houses, in fields, in
woods, in the ground, under stones, in trees, in roots, and in all
other likely and unlikely places. They are abundant in temper-
ate countries, more rare to the northward, but become veritable
pests by their enormous numbers in the tropics. They have
many peculiarities of habit, and their development is remarkable
in certain directions. We find among them architects and
builders, agriculturists, masons, tailors, and many of the other

THE INSECT WORLD.

391

trades and professions are represented. We find communities
governed in some directions despotically by a queen, yet at the
same time forming the most perfect republic, in which every indi-
vidual has its rights firmly established and absolutely beyond the
control of the nominal head of the colony. We have organiza-
tions that make war, keep slaves, lay in stores, and provide for
contingencies ; they seem able to forecast the future in some
directions and intelligently provide for it. In other words, they
offer some of the most interesting problems that can possibly be
studied. It is unnecessary to waste words in describing the ap-
pearance of an ant, and it need only be said that all the true
ants are distinguished from the other Hymenoptej-a by the posses-
sion of one or more scales or nodes on the petiole or stalk of the
abdomen. We find also, in this series, the development of what
are known as " neuters," or workers, —that is to say, female indi-
viduals in which the sexual characters are not perfected, which
are incapable of reproduction, and whose function in the nest is
simply to perform the mechanical labor necessary to keep up the
colony. These workers have no wings, and in their appearance
and the relative proportion of the parts they frequently differ
considerably from their parents. There are sometimes several
forms of workers found in nests, differing from each other in the
development of certain parts for special purposes, but attention
will be called to these hereafter, where necessary. Though the
ants agree in their general habits and peculiar social organization,
yet no less than five different families have been recognized,
based upon structural characters, principally of the abdomen and
head.

The most numerous in species of these families, containing
most of our common forms, is the Formicidce, in which the
petiole is formed of a single joint only, and the abdomen is
smooth, without constriction between the segments. In this
family the "queens," or females, have no sting. They build
their nests in all sorts of localities. We find them commonly in
our fields; often in woods, where the large black "carpenter
ants' ' are the most prominent ; while some occur under stones
or around the roots of trees. It would be easy to write a book
on ants alone, but necessarily our notes of them must be con-
fined here to the features of economic importance. And first

392

AN ECONOMIC ENTOMOLOGY.

let us have their general life history. In a colony of ants, how-
ever large, there is usually a single "queen," or female, the

nominal head of the estab-
FiG. 450. lishment, and she attends to

the business of laying the
eggs, which are white, cylin-
drical, and a little elongated.
They are taken in charge by
the workers, cared for, and
in about a month — the time
varying with the species —
helpless grubs are produced.
These are carefully tended
and fed, because absolutely
unable to help themselves,
are periodically cleaned and
moved about from place to
place in the nest, that they
may have the proper degree
of warmth and dryness or
moisture, and after about six
weeks of this coddling they
are full grown. Then they
either spin an oval cocoon,
in which they change to
pupae, or change directly
without forming such a cov-
ering. The cocoons are cared
for as tenderly as were the
larvae themselves, and these
are what is usually known as
' ' ants' eggs. ' ' They may be
found at midsummer, or thereafter, in almost any colony of ants,
and usually in the upper chambers of the nest, where they get a
full supply of warmth from the sun. The adults hatch from these
cocoons late in summer, and at once take part in the work of the
nest, so far as they are workers. Of the latter there may be
two forms, known as "worker minors," or small workers, and
" worker majors," or large workers, each with different duties.

Cremastogaster luteolata. — a, b, large
worker ; c, its head ; d, female ; e, its wing ;
/, small worker. Family Formicidce .

THE INSECT WORLD.

393

There are also two kinds of winged forms, males and females,
both larger than the workers, and the females considerably larger
than the males. All the insects work their way down to the
lower levels or inmost galleries of the nest on the approach of
cold weather, and hibernate in the adult stage in a dormant con-
dition. In spring, with the approach of warm weather, activity
is resumed, and, usually some time during the early part of the
season, on a particularly bright, warm day, the newly developed
males and females leave their old home and "swarm." By this
is meant that they leave the nest in which they were hatched and
fly about for a short time. They mate soon after, and are then
ready to start colonies of their own. None of them ever get
back to the old home, and if they do not succeed in founding a
" hill," they perish in the course of a day or two. Exactly how
the different species start their colonies is not known, but in some
cases, certainly, the impregnated female strips off her wings and
starts a small nest in some convenient place, doing the best she
can under the circumstances, and laying only a few eggs. These
she brings to maturity, and they are usually of the small or
"worker minor" type. When fully developed, these relieve
their parent from further mechanical work, increase the size of
the nest, and gather food as well as attend the young that are
still continually hatching. If circumstances favor, the nest grows
rapidly, and it may eventually become enormous in size, con-
taining millions of individuals, and ramifying for distances that
we have not yet succeeded in following to the end. The life cycle
of all the ants has not been definitely determined as yet, but
' ' queens' ' have been kept as long as seven years and workers for
three or four. The food of ants is variable, — sometimes animal,
sometimes vegetable, and quite usually both. The same species
may feed upon fragments of insects and other animal matter, and
also upon plant tissue of various kinds. They are usually fond
of liquid food, especially if it is sweet, and some species gather
and store honey like the bees, although in quite a different man-
ner. In the more temperate parts of the United States ants
are only indirectly injurious, although they are never beneficial.
There is quite a common belief that ants destroy the plant-lice
among which they are frequently found ; but this is exactly con-
trary to the fact, for plant-lice play a very important and curious

394

AiV ECONOMIC ENTOMOLOGY.

part in the economy of certain species of ants. As we learnt in
the chapter on plant-Hce, these insects are furnished with a pair
of honey-tubes near the end of the abdomen, through which there
is excreted a sweet, almost transparent, liquid, of which the
ants are very fond. In many cases aphids live on the roots of
plants during the whole or a part of their life, and such species
are in nearly every instance carefully tended by ants. We may
find, on lifting up a large stone at the foot of a tree near the
edge of a wood, that all the little rootlets covered by it are clus-
tered as thickly as possible with plant-lice, and that around them
the earth has been carefully tunnelled out ; in other words, we
have the roots forming part of the nest system of an ant colony.
As the plant-lice increase in number, additional roots are laid
bare, and the young are transported to them that they may
always find an abundance of food. In return, the ants, whenever
the desire seizes them, call upon one or more of the aphids, and,
by touching them with their antennae, induce them to give up
a drop or two of their sweet secretion. Exactly how large a
proportion of the food of the ant colony this kind of material
forms is yet undetermined ; but certain it is that plant-lice con-
stitute a very important element in the supply of some species,
and fully represent our cattle for all ant purposes.

Little brown ants about three-sixteenths of an inch in length
occur very abundantly in the fields throughout almost all parts
of our country, building small underground nests. These ants
belong usually to the genus Lasius, and may be found, especially
early in the year, on the leaves of all sorts of plants infested by
aphids. In melon and sweet potato fields they are often ex-
tremely abundant, and it is more than likely that they are active
in transporting from one plant to another the lice infesting these
particular crops. Of the Lasius bnnineus, we know that it tends
the corn-root louse, gathering the young larvae in the fall and
preserving them during the winter safe beyond the reach of any
natural enemies, colonizing them in spring upon the roots of corn
plants. Indirectly, therefore, these ants are decidedly injurious
through their relation to the plant-lice. Other species gather
plant-lice eggs and care for them during the winter, colonizing
the young upon proper food plants in spring.

We find certain other species making their hills in our lawns

THE INSECT WORLD. 395

and gardens, or in grass-plots, and they are sometimes decidedly
troublesome in such localities. Where this occurs, there is noth-
ing better for getting rid of them than bisulj)hidc of carbon. Pour
a quantity into each of the openings of the disk or hill, closing
them up by stepping on each as it is treated. The fumes will
penetrate the chambers in every direction, and if a sufficient
amount has been used, will kill not only all the adults, but all
larvee as well. A single application is usually all that is necessary ;
but in a very large colony it may sometimes happen that the
farther chambers are not reached by the fumes, and that the nest
reappears near by ; rarely in the old spot. When that occurs, a
second treatment is tolerably certain to be effective. It has been
recommended that, to get the best results, holes be poked with a
stick into different parts of the hill, but I have not found this of
any great advantage. It has also been recommended that, after
pouring a considerable quantity — say three or four ounces — into
the main opening of the nest, the vapor be exploded by means
of a match held at the end of a stick. When this is done the
nest is completely wrecked, and the poisonous vapor is forced to
every portion of the galleries, so that escape is almost impossible ;
while larvae and pupae are buried so thoroughly that they can
never make their way to the surface, even if not killed by the
fumes. This is a very good method where a large nest is to
be dealt with ; but whoever attempts it must remember that the
vapor of the bisulphide is exceedingly inflammable, and must
make certain that he is far enough from the opening of the nest
to prevent being caught by the flash. Ants are never desirable
in a cultivated field ; they have no business there, and are cer-
tainly of no benefit to the farmer, even if they do not directly
feed upon plant tissue.

Wherever the corn-root louse is injurious, late fall ploughing
should be practised to destroy the nests of the ants. If the
ploughing be done before the ants have gone into winter-quarters,
they will either build a new nest sufficient for their purpose, or
will move with their belongings to a spot in which they are able
to winter ; so no good will be accomplished. If the ploughing
be deferred until frosty nights and cool days discourage activity,
the ants will be unable to repair damages, or will not have suffi-
cient time to re-establish themselves before they become torpid.

396

AN ECONOMIC ENTOMOLOGY.

The ploughing should be deep and as thoroughly done as pos-
sible, so as to not only disturb and break up the nests com-
pletely, but to scatter the plant-lice, eggs, or other material that
the ants may have gathered. By this simple means injury may
frequently be prevented during the year following.

Incidentally it has been mentioned that some species of ants
gather honey and store it ; and, curiously enough, instead of
building cells for its reception, as do the bees, a special form of

Fig. 451.

Honey-ants, Myrmecocystus melliger, filled with honey.

worker is developed, with an unusually elastic crop and abdo-
men. These specimens are simply stuffed by the other workers
until they become of the size of a small cherry, utterly helpless
and incapable of motion. In this condition they cling to the
walls of the nest until, in the course of time, their stock is used up,
when they again resume activity.

Three of the other ant families to which reference has been
made contain no species of particular interest to the farmer, how-
ever interesting they may be to the student.

But in the family AlyrmicidcE we again find species that are
numerous and of more or less importance to man. Here the
petiole of the abdomen is two-jointed, differing thus from the
other important family, FormicidcE. Many of the species have
the sting well developed in workers and " queens," and are for-
midable creatures by reason of this weapon ; but not all our forms
are so furnished, as is known by those who have suffered from an
invasion of small red ants in houses. This little creature, Mono-
morhtm pharao)iis, sometimes occurs in myriads, and nothing is

THE INSECT WORLD.

397

safe from it. Sue^ar is especially attractive, but almost anything
is attacked, nothing more readily than a bone from which the
meat has been roughly scraped, and which is yet a little bloody.
It seems impossible to get rid of these creatures, because they
avoid poisoned food and anything that has
the appearance of a trap. A few specimens I'u;. 452.

may be killed, but very soon the character
of the mixture is recognized, and it is left
untouched. " Insect-powder" — pyrethrum
— is effective, but it is practically impossible
to get it everywhere, and the ants simply
avoid it. Carbolic acid and naphthalene are
both useful as repellents : the insects dislike
th'e odors intensely, and will not approach
these materials ; but while certain closets may Monomorium pharaoms.
be protected in that way, the odors are not
particularly desirable near food products, and are as repugnant
to many persons as they can possibly be to the ants them-
selves. The simplest method, perhaps, is mechanical destruc-
tion, as follows : Where meat is used every day, the bones, or
some of them, should be cut out before it is cooked and placed
in a main line of insect travel. When they become thoroughly
covered with hundreds or even thousands of ants, the whole mass
should be thrown into the fire. If this process is repeated two
or three times a day, a few days in succession, the ants seem to
be seized with a panic, and usually abandon the house com-
pletely. Instead of bones, a sponge dipped in sugar water and
loosely pressed out may be used ; or, better yet, there should be
two sponges. The sweetened one should be placed where the
ants run, and the news of its presence will spread throughout the
entire house in a remarkably short time. When the first sponge
is entirely filled with ants, the second should be prepared in the
same way to replace the first, which is to be taken up and put
into boiling water. This destroys the insects at once, and the
sponge can be washed out, again dipped in the sugar water, and
used to replace sponge number two when that is filled with in-
sects. Here the same effect is obtained : the insects are seized
with terror, and seem to realize the presence of a force that
they do not understand. The sudden lessening of their numbers

398 AN ECONOMIC ENTOMOLOGY.

strikes them with such horror that they abandon not only their
nest but the house itself. I have myself used this method on
two occasions, and have recommended it frequently to others ;
in every case with the best results.

To this family belong the so-called "agricultural ants" of
Texas and the Southwest, some species also occurring in Florida
and other parts of the Southern United States. These build im-
mense underground nests, and keep on the surface a cleared
space varying in diameter according to the size of the colony.
They cultivate grasses on these plots, of the seeds of which they
are especially fond, and which they store in their galleries. Their
food, in fact, consists mainly of seeds of various descriptions,
and these they gather from whatever plants there may be in the
vicinity. The insects are very abundant in some localities and
are great nuisances in cultivated fields, not so much from what
they actually destroy by eating, but from the fact that they tol-
erate nothing in their vicinity except what suits them. They
have no particular use for corn or cotton, and ruthlessly cut
down every stalk that encroaches on their domain. The only
substance that has been employed against them with any degree
of success is bisulphide of carbon, and this should be used in
quantities depending upon the size of the nest. In these cases
the vapor should be exploded in order to produce the best re-
sults. The nests extend for so long a distance underground that
the insects will not be reached otherwise, and when the material
has entirely evaporated, the galleries are again useful to them.
On the other hand, the explosion shatters the entire nest, and
the insects that escape in remote galleries are not likely to start
again on the same soil, unless the queen also has escaped. It
has been already indicated that such a nest is a complicated or-
ganization. It contains not only its owners with all their races
and castes, but frequently also slaves, — other species of ants that
have been conquered and stolen while in the larval or pupal
state, and which now perform all or a great portion of the manual
labor of the colonies. It often contains also not only plant-lice,
but coccids, which are cared for in the same way, and occasion-
ally other species of Homoptera, such as tree-hoppers. We
find, in addition, numerous species of insects that seem to take
the part of guests. Some of these are scavengers, and they evi-

THE INSECT WORLD.

399

dently keep the nest clean and remove decaying particles ; others
may be of some use to the ants by excreting certain sweet sub-
stances which induce their toleration ; while yet others have no
use at all, so far as we can discover. Such are certain crickets
which are always found associated with ants, and certain cater-
pillars. What functions these insects have in the anthills is as
yet somewhat obscure.

In the tropics there are species that occasionally change their
camps, and are known as foraging ants. When the whim seizes,
or unknown causes determine them, they leave their nest, bag
and baggage, attended by all the insects that lived with them,
and start upon a march straight forward, destroying everything
that attempts to prevent their passage. A house or a village is
no barrier ; they pass through or over it, destroy every living
thing it contains, and devour all the provisions. The inhab-
itants of countries subject to these foraging expeditions soon
learn to recognize their character, and immediately seek safety
in flight. The ants continue their march, and soon the house
or village can be reoccupied, with the certainty that, if all the
provisions have been cleared out, so also have all the vermin :
rats, mice, snakes, roaches, and similar creatures being all killed
and eaten.

The battles of ants have been described by more than one
author ; but as this is the function of another kind of work,
nothing more will be said here about these very interesting
creatures.

Next in the orderly series come the Fossores, or "digger-
wasps." Here the two normal sexes only are developed, and
they are solitary, — that is, they never form communities. They
often build their nests underground, preferring sandy spots ; but
the families vary much in this respect. The females are always
provided with a sting, which they use on slight provocation, and
they differ from the next family of true wasps by having the
wings always flattened and never longitudinally folded in repose.
Sometimes, instead of burrowing underground to form their cells,
they use the stems of pithy plants like alder and sumach, and
often nests are built of mud, in sheltered localities against houses,
barns, or other convenient places, or even attached to twigs or
shrubs.

400

A.V EC 0X0 MIC ENTOMOLOGY.

Fig. 453-

A velvet ant, Splicer
ophthalma occiden
talis.

Occasionally we find, running on sandy spots, an insect that
looks like a large ant, very prettily colored and banded with
bright scarlet and black, rusty red or mottled yellow. If one of
these apparent ants be picked up, the result
is usually a surprise in the form of an enor-
mously long sting, for we really have a wing-
less "digger-wasp," which from its appear-
ance and habits has been called a "velvet
ant." Just what the breeding habits of these
Mutillidce are is not known, but they are sup-
posed to be parasites, or at least to lay their
eggs in the nests of other species of Hymen-
optera. There is considerable difference be-
tween the sexes, and the males are winged
even when the females are wingless, the wings
being usually blackish in color.

Another series of "diggers" belongs to the
family Scoliidce, and these may often be seen
quite early in the spring, flying close to the
surface of the ground, with a buzzing noise. Often they are
found visiting flowers, particularly the males, which are some-
times quite abundant when raspberries are in bloom. These in-
sects, so far as we know
Fig. 454. their habits, lay their eggs

in underground larvae,
which are then devoured
by the young of the wasp.
The common "white
grub," the larva of Lack
nosterna, is subject to the
attacks of one of these
species, Tiphia inornata,
a black wasp, rather sparingly clothed with fine white hair, and
sometimes attaining the length of three-fourths of an inch ; and
there are others that attack our injurious underground species of
all orders.

In the family Pompilidce we have a series of rather stout,
black forms, quite frequently banded with red on the abdomen,
while sometimes the entire insects are more or less red. They

White-grub parasite, Tiphia inornata. — a, ima
go; b, head of larva; c, larva; rf, cocoon.

THE INSECT WORLD.

401

usually have a velvety appearance, or look as if they were cov-
ered with a whitish bloom, and the wings are also either black or
yellow, like the prevailing colors of the body. They lay their
eggs in spiders, which they bury, and in which the larvae de-
velop. Perhaps this is a good place to mention the fact that
these digger-wasps make use of their stings and the poison se-

IMC. 455

Pepsi's forntosiis, tarantula-hawk.

creted by them for preserving from decay and in a condition
suitable as food for their young the larvae, spiders, and other
insects upon which they feed. They sting their prey very care-
fully, in such a way as to paralyze and render it motionless,
while yet it does not die ; and the larvae, when they hatch, begin
feeding very carefully, so as not to kill their host until they them-
selves are sufficiently developed. The poison introduced seems
to simply suspend life, or rather allows it to go on without a
waste of tissue. Spiders of all kinds are attacked, and even the
fierce tarantula of the South and Southwest has its enemy in an
enormous species o{ Pepsis known as the " tarantula-hawk."

Perhaps the most common forms belonging to this series are
those in which the abdomen ends in a small bulb-like structure

26

402 AN ECONOMIC ENTOMOLOGY.

connected with the thorax by means of a long stalk or pedicel.
These belong to the family Sphecida, of which the majority
build their nests underground and provision them with spiders,
caterpillars, or other larvae. Others, known as " mud-daubers,"
species of Pelopceus, plaster their nests against out-houses, in all

sorts of corners and under all sorts of
shelters. They are sometimes built
singly, but usually in groups, and may
consist of either a shapeless mass of
mud, or may be regularly arranged,
often with ribbed sides. The insects
that build these nests are either metal-
lic blue, or black marked with yellow,
and here the pedicel connecting the
abdomen with the thorax is unusually
A mud-dauber. Peiopcus ^ ^^^ slender. The mud is carried

species. "^

by the insect with its forelegs and jaws,
and is applied carefully, pellet by pellet, to the nest, until the
cells are completed. Then they are stored with some one kind
of insect as food for the larva. If the insect begins on caterpillars,
it continues to collect caterpillars, all of the same species, stinging,
as already described, so as to paralyze them, and then packs
them away in the cavity as closely as possible. Finally, when a
cell is full, an egg is introduced ; and now, when the young wasp
hatches, it finds food in abundance at hand, and simply lives upon
this supply, taking one caterpillar after another, or one spider
after another, as the case may be. Some small species store their
nests with plant-lice. These insects are to be considered as de-
cidedly beneficial, and if the nests are sometimes unsightly and
the wasps themselves a nuisance, yet, taken all in all, they deserve
encouragement. The number of caterpillars destroyed by them
in the course of a season is enormous. I have counted thirty
canker-worms in a single cell, and have sometimes opened nests
in which there were an even greater number of small Tortricid
caterpillars. Any insects which destroy as many caterpillars as
do these wasps deserve our best consideration and should not
be wantonly destroyed. Another peculiarity to be noticed in
opening the nests is, that the insects, whether caterpillars or
spiders, are all of just about the same size, as if the mother had

THE INSECT WORLD.

403

exercised great care in portioning out the food to the best ad-
vantage. The adults may often be found on flowers, and when
the golden-rod is in bloom in late summer, some of our largest
and most attractive species, like Sphex ichneiimonea, make their
appearance in great abundance.

The allied "diggers" belonging to the Larridcc have the
abdomen more closely joined to the thorax, and provision their
nests, which are made underground, with small grasshoppers.
The insects are not nearly so common or so numerous in species
as those previously mentioned, and are chiefly inhabitants of the
more southern States.

In the BenibecidcB we have many large, brightly colored spe-
cies, some of which prey upon cicadas, stinging so as to render
them helpless, and carrying them oft' to their nests as provision
for their young. It is interesting to watch a specimen of Sphe-
cms speciosus when it has a large cicada to be transported. If
the insect is captured and

paralyzed upon a tree, the ^^' ^^'^'

wasp drags it along the
branch to some convenient
point, and from it flies as
directly as possible towards
its nest. Sometimes its
strength is not sufficient to
sustain the weight, and
then it is drawn gradu-
ally to the ground. In
such case it again drags the
insect to the top of some
convenient shrub or tree,
and makes another eftbrt,
again flying as far as pos-
sible before allowing itself
to be pulled down, but always arranging matters so that it is able
to make a new start from an eminence. In other words, the wasp
is often unable to lift the cicada from the ground in direct flight,
but is able to drag it to an elevation sufficiently great to fly a con-
siderable distance before being drawn to the ground, and in this
way, after a time, it manages to reach its nest. These Bembecids

Sphecius speciosus carrying a cicada to its home.

404

AN ECONOMIC ENTOMOLOGY.

are quite numerous, and the abdomen is conical in shape, con-
nected with the thorax by a very short and slender neck, or
pedicel, more resembling the true wasps than any other of the
species that we have been considering.

There are several other families with similar habits, differing in
appearance to some extent, and varying in the character of the
insects used in storing their nests. Among the families contain-
ing the smaller species we find those types that burrow in pithy
plants and prefer small insects for provisioning their nests : —
flies, plant-lice, and small spiders being the most usual supplies.

Taken as a whole, all the digger-wasps are useful insects, and
they require for food, in the course of a season, a very large num-
ber of specimens injurious to plant-life.

The "true wasps," or Vespidce, are distinguished from the
"diggers" by the fact that the fore-wings are folded longitudinally
when at rest, and this is a character easily seen and quite distinctive.
We have among them solitary and social forms, — the solitary
types so called because only the two normal sexes are present, and
because they do not live in colonies. There is a great variation
in habit, and we find species that bore in woody tissue, some
that inhabit pithy plants, some that burrow in the earth, and

others that make mud
nests. The mud nests
vary in form and are
often quite pretty, those
of Eumenes resembling
a jug or vase attached to
the twigs and stems of
plants. It is not always
possible to distinguish be-
tween the cells and nests
of the diggers and those
of the true wasps, and
practically it is a matter
of no importance, because
the habits of the insects are similar, — that is, they store their
cells with insects upon which their larvae feed. All solitary
wasps are beneficial, therefore, and should be encouraged by the
farmer.

c

Fralenial potter-wasp, Enmrnes fiatrrna. — a,
wasp ; b, its cell ; c, same broken open to show the
caterpillars stored in it.

I" ir.. 458.

I'lc. 4()i

Kig. 458, a, .arvF. ; *, c, pupa, from beneath and side; ,■,/.,<>■. slructiiral details, o(
Sfiheciits speciosus. FiR. 459, larva of Sfihrriiis sfircinsiis fccdins on cicada in its under-
ground burrow. Fig. 461, nest of l/espa inaailata, just started.

THE INSECT WORLD. 405

In the social wasps we find a step towards the organization
found in a beehive, sometimes well and sometimes very poorly
marked ; i)ut in all cases, besides typical males and females, there
is a worker caste, which, as in the ants and bees, is composed of
sexually undeveloped females. Briefly stated, the history of
these wasps is about as follows : Males and females appear in
fall ; the females are impregnated and live through the winter in
such shelter as they are able to find ; in the spring, with the ap-
proach of warm weather and the opening of the flowers, the
females revive, and at once begin reproducing their kind. They
start a small nest of only a few cells, and lay eggs in them as soon
as they are well started. In a few days the larvae hatch; the
female increases the size of the cells and adds to them, and to her
other duties is now added the care of the newly hatched young,
which must be fed and tended daily. In three or four weeks the
first larvie become full-grown, and the cells are then capped by
the mother. In this closed cavity the change to the pupa takes
place, and in due time an adult appears. This adult is a worker,
or undeveloped female, and at once begins to help the original
mother in the work of attending to the brood and increasing the
size of the nest. Until midsummer, at least, workers only are
produced ; but then, when the brood of workers is sufficient to
relieve the stem mother of all necessity for labor, eggs are laid
that produce sexually complete forms, — males and females, — which
generally issue during the first days of September. The old
female now dies, and when cold weather sets in the workers
and males also succumb, leaving only the impregnated new
females to live through the inclement season. Of course there
are many modifications of this general life history, and some colo-
nies become very much larger than others. In some instances
the cells seem to be used over and over again, and no more are
manufactured than is necessary to accommodate the brood. In
other instances it seems as if the cells are used only once, and
new ones are built for each individual larva. The locality in
which the nests are built also varies, although the general char-
acter of the comb, or cell, is nearly always the same. As a home,
some species, like the " yellow-jackets," select a little cavity un-
derground ; some, like the giant Vespa crabro, a hollow tree ;
some a favorable spot among the branches. Others build un-

4o6 AN ECONOMIC ENTOMOLOGY.

protected combs in the shelter of a projectuig ledge of rock, or
under the eaves of houses, or even under fence boards ; while yet
others build their globe-shaped structures openly upon bushes,
and these are usually termed " hornets." The material of which
the nest is composed is a sort of wood-pulp paper. The insect
scrapes a small bit of wood-fibre from an exposed surface, mixes
it with saliva, kneads it into shape, and then, by means of the
mandibles and forelegs, spreads it in a thin layer and attaches it
to the surface at which the nest is to be started. Layer after
layer of fibre is added in this way until the nest is completed.

The enormous structures made by
^''^'- 4^^- ^ the " white-faced' ' wasp, Vespa

maculata, are excellent examples of
what can be accomplished by num-
bers and persistence. As to feed-
ing habits, these social wasps are
usually predaceous, but they are
also fond of sweets, and may often
be found on flowers, gathering
White-faced uasp,;v.Av «;««,/,./«. ^^o^^y, or on ripe fruits, sucking

their juices. We also find them
occasionally in butcher-shops, and they have a fondness for
chewing into raw meat and lapping the blood. They feed their
larvae honey and other plant juices, and also the masticated frag-
ments of insects. That is to say, they prepare the animal food
by first chewing into a pulp before feeding it.

Two types of these wasps are common throughout the United
States, — the first rather slender, with a spindle-shaped abdomen,
and usually a more or less red-brown color, often marked with
yellow. These belong to the genus PoHstes, and they build their
paper combs openly, — that is, without any covering, and sus-
pended by a single, short, central stalk. The colonies rarely
become very large, but they are very numerous in most parts of
the country.

The true "wasps," or members of the genus Vespa, have the
abdomen cylindrical, squarely cut off where it joins the thorax,
and are very often contrastingly marked with white or yellow,
occasionally with red or brown on a black ground. These are
the "hornets" and "yellow-jackets," and their colonies some-

THE INSECT WORLD. 407

times become of enormous size, many hundreds of individuals
being found in a single nest in the latter part of the season.
Durability is not looked for by the insects, and the winter storms
and snows disintegrate the paper structures, so that in spring it
is rarely possible to find them, however abundant they may have
been during the summer previous.

Wasps are beneficial, as a whole, since they feed largely upon
other insects and never directly upon crops. They are a nui-

FiG. 463,

Nest of PoUstes i^allicola.

sance sometimes in the orchard, where they are apt to attack all
fruits that show the least trace of injury or decay, and they have
been accused, as, indeed, have the bees as well, of actually punct-
uring juicy specimens to get at the liquid contained in them.
Some of the species are undoubtedly useful in pollenizing fruit
flowers, but there are none of pre-eminent advantage in this di-
rection.

The last family in the order contains the bees, and these, as in
the wasps, may be either social or solitary. The solitary bees
are those in which male and female only are developed, and their
habits in nest-building resemble in many cases those of the
wasps. Thus, we have species that build in the ground, those
that make cells in the pith of plants, others that are true carpen-
ters and bore tunnels in solid wood, and, in short, we may find
bee homes in much the same situation that we find wasp domi-
ciles. Their cells may be distinguished, however, in all cases by

4o8 AN ECONOMIC ENTOMOLOGY.

the fact that they are stored with a mixture of pollen and honey,
or honey or pollen alone, instead of with insects, and it is this
habit of collecting pollen that makes the bees so highly useful to
the farmer, by their incidentally pollenizing the flowers from
which the material is gathered. There are several interesting
structural modifications in the bees to facilitate the work of gath-
ering both pollen and honey, and, incidentally, of accomplishing
pollination to the best advantage. Thus, the clothing, instead
of being composed of simple cylindrical processes, is com-
posed, in large part, at least, of bristly, plumose or twisted
hair, — that is to say, each hair is furnished with Httle spurs,
or long, slender branches, making it resemble a plume under
the microscope. Or it may be twisted like a screw, or fur-
nished with a knob at the tip. The result is, that as the insects
move over the flowers, the pollen grains adhere to the vestiture,
and this also accounts for the fact, probably noticed by every ob-
servant fruit-grower, that bees frequently bury themselves com-
pletely in the blossoms, or roll over every part of them. Such
insects are after pollen, not honey, and by so rolling about the
pollen grains are brought into contact with and adhere to the
surface of the insect. Incidentally, also, as soon as the bee flies
from one flower to another, and repeats this operation, a sufficient
number of pollen grains from the first flower adhere to the stigma
of the second and poUenize it ; while in flying from one tree to
another, cross-pollination is accomplished. The flowers visited
in this way by a single bee are very numerous. When a honey-
bee becomes more or less covered with pollen, it cleans itself by
means of specialized structures on the legs, which enable it to
literally comb out its entire body covering. The masses of pol-
len gathered in that way are then rolled into a lump and fastened
to the upper side of the posterior tibia, where lateral fringes of
long hair hold it in place and actually form a basket. These
combing arrangements are situated on the first joint of the hind
tarsi, which is broadened for that purpose in the social bees, and
is usually much longer than the other tarsal segments. Some
bees have pollen baskets not only on the tibia, but on the femur
and coxa as well, and occasionally the whole posterior portion of
the thorax and the space between the thorax and abdomen is
utilized to store the pollen masses. Sometimes the under side of

Ik.. ^04.

A iilatc- of bees.-,/, .\fr/is.\(>({,s /uiiiacu/alus .■ />, Aintiriia vunni : c . (.'irlioxvs S-driitala : d,
Haltctus ligatus: r, Sytilnilomia aliivriiliis;/, Ostiiiu i/is/ici.-g. Andirua riigrniic : //, Mrlis-
sodrs iiisiip/s: i, Mcsriuliilr mciidica : k. Xriinglossii /»niiiiia: I, Tachylcs mandibularis ; m.
Mrfrachil,- laliiiiaiius. All lallu-i more than twice tiatiiial size.

:^^gS^;^!^^';^^fkf<;x';v^4^

- _ -t 4- ^ — * «— <3 — ^ «: ^ ^—^ ^ ,,-- jT ijf

T~T^C ; »-g^

409

4IO

AN ECONOMIC ENTOMOLOGY.

the abdomen contains the pollen-gathering structure, — that is to
say, the segments of the abdomen are furnished with brushes of
long, twisted or knobbed hair, and all the pollen gathered by the

Fig. 468.

Fig. 469.

Modifications of the hind legs of different bees.— /I, Apis: a, wax cutter and outer
view of leg; b, inner aspect of wax cutter and leg ; c, compound hairs ; d, anterior leg,
showing antenna! scraper. £, Melipona : /, peculiar group of spines at apex of tibia;
g, inner aspect of wax cutters and first joint of tarsus. C, Bomdus : h, wax cutter; i,
inner view of same and first joint of tarsus ; all enlarged.

insect is stored among it, ready for transportation to the nest.
Pollen, however, forms only one portion of the food of the larva,
and it must be mixed with honey to form " bee bread" of a proper

composition. This honey is also
gathered from flowers, and the
mouth parts are modified to this
especial end.

We have two series of bees dis-
tinguished by the character of the
mouth parts, — the short-tongued
and the long-tongued, — both of
which may be either solitary or
social. The short-tongued bees
have the lower lip modified into a bladder-like structure, more
or less pointed at the tip, and set with regular rows of short hair
or flattened processes, an ideal tongue for gathering up the liquid
nectar and bringing it into the mouth. Many of these bees are
diggers, and build their nests in the ground, usually forming a
single vertical burrow from which lateral branches diverge into

Abdomen of Megachile fitted for
gathering pollen.

THE INSECT WORLD.

411

IG. 470.

small cells, each containing a supply of food sufficient for a
single larva. The mother bee constructs a cell, fills it with a
mixture of pollen and honey, and
lays an o^^^ in it. Then she closes
up the chamber, and her work as
to this particular larva is com-
pleted. When the q^^ hatches,
the larva finds a food supply im-
mediately at hand sufficient to
bring it to maturity. When it is
fully grown it changes to a pupa,
and eventually to an adult, which
then makes its way from the earth-
en home into the sunlight. The
mother bee having completed one
cell, at once begins the construc-
tion of another, and thus the
w^ork is continued until the supply
of eggs is exhausted. The open
face of sand- or clay-banks is a
favorite place for these insects, and
sometimes they build their nests
together in great numbers.

The long-tongued bees are so
called because the ligula or glossa
is extended into a flexible ribbon-
like structure, ringed but not seg-
mented, set with circles of long
hair, and frequently tipped with a
little button-like structure. This
enables the insect to reach the
honey in deep flowers like the
clovers, and in fact there are only
certain bumble-bees with a tongue
long enough to reach the nectaries
of the red clover flowers ; hence

they are entirely dependent upon these for pollination. Destroy
the bumble-bees, and no red clover-seed can be obtained. It is a
suggestive fact that in many localities where ruthless war is waged

vrv<^>^

Buiiowol in ii ita show 1111; lcIIs 111
...der v^f cc.j^l^t.v,.. , tl.e f.rot .a c», U.e
last aty, in which an egg has just been

laid.

412 AN ECONOMIC ENTOMOLOGY.

against bumble-bees, it is becoming increasingly difficult to obtain
clover-seed, and for this particular purpose those insects should
be carefully cherished. They are sometimes a nuisance when in
the course of mowing or reaping a nest is disturbed, but the
slight annoyance then caused scarcely warrants the complete de-
struction of the nest which so uniformly follows. The farmer
who destroys every nest of bumble-bees on his land destroys a
series of insects than which none are more useful to him, particu-
larly if he raises fruit or has any desire to obtain red clover-seed.
The long-tongued bees may be either social or solitary, and
there is no superficial character known to me by which the solitary
bees can be readily distinguished from the social forms, except by
the presence of the wax-producing organs in the latter. The
habits of the bees differ greatly: some are cuckoos, some have been
supposed to be parasitic, while the majority are undoubtedly
honest workers and provide decently for their families. Many of
them, as has been already stated, are carpenters, and some of them
are tailors or upholsterers as well,— that is to say, after having
bored out the wooden tunnel in which the family is to be raised,
the cells are constructed of leaf fragments. Rose leaves or those
of other plants of the family RosacecB are frequently noticed with
circular or semicircular pieces cut from the edges. This is done
by a bee of this tribe, usually a Megachile, and these little frag-
ments are used in constructing a somewhat thimble shaped cell.
When one of them is completed it is filled with pollen and honey
and an Qgg is laid in it ; then another is built on top of it, and so
on until the burrow is completely filled. As the undermost
specimen matures first, it bores to the surface through a hole at
the end, to avoid the necessity of working its way through all its
younger relatives above it. The largest of our carpenters is the
Xylocopa virginica, which is generally mistaken for a Bombiis,
being fully as large, as robust, and colored yellow^ and black,
with a metallic blue reflection on the abdomen ; but the head is
very much broader than in any bumble-bee, and equal to the
width of the thorax itself The eyes also are larger and white
or yellowish in color, distinguishing the insect at once from true
Bombus. This species makes galleries half an inch in diameter
in the solid wood, and raises a considerable family in the course
of the year. The partitions between the cells are made in this

Fig 471.

Mouth of bumble-bee. — The liexible tongue central, flanked by the long: palpi; the lateral

parts are the maxillae.

THE IXSECT WORLD.

413

case of little chips of wood cemented together. They are very
common and sometimes troublesome where they make their

galleries in the wood of piazzas and out-buildings of country
houses. Nothing will be gained by giving detailed descriptions
of these solitary bees, since their general habits are practically

414

AN ECONOMIC ENTOMOLOGY.

alike, and it need only be said that all are useful and none are
in any true sense of the word injurious.

The social bees are among the most interesting of all the
insects, yielding only to the ants in the perfection of their colo-
nial organization. The domesticated honey-bee. Apis mellijica,
may be accepted as the type of the highest development in this
family. Here we have in each hive a queen, or fully developed
female, who is often, under normal conditions, the mother of
every individual contained in it. She does not labor, is carefully
tended by workers who provide for all her wants, and her only
function is to supply a sufficient quantity of eggs for the brood-
cells. The comb made by the hive-bee is so universally known
that no time need be wasted in describing it ; nor is it important
to say just how the wax is produced, save to state that it is
excreted by special glands on the under side of the abdomen of
the workers in plate-like masses. These are gathered together,
kneaded by the jaws, and placed in position on the comb. These
waxen cells are used either as cradles for the young or for storing
the honey against such time as no food can be obtained ; for,
unlike the bees previously spoken of, the whole colony lives
through the winter, and requires a certain amount of food to
maintain it until work can be resumed the spring following. Of
these storing habits man has made use ; but there are a number
of wild species belonging to other genera than Apis that have
similar tendencies. The life in a hive proceeds something as
follows : the workers, who are the real rulers, determine about
how many young should be raised during the season, and build
the proper number of brood-cells, making three distinct sizes.
The smaller are intended for workers, which here, as elsewhere
in the Hyme7ioptera, are simply undeveloped females ; the
larger are to contain males or drones ; while a very few, irregular,
somewhat flask-shaped cells are plastered at the sides of the
combs, and are intended for new queens or perfect females. The
queen lays an o^g^ in each of the brood-cells, and never makes a
mistake in its character. She lays drone eggs in the drone cells,
and drones only are produced from them. In the worker cells
workers only are matured, while in the queen cells fully developed
females are raised. It is interesting to note that the insects have
the matter of sex under perfect control, and it is believed that

TIIK INSECT WORLD.

415

the eggs producing drones are not fertilized : this matter being
under direct volition of the female. The larvce are carefully fed
by the workers, and each variety receives a different kind of
"bread," especially prepared for it. The workers are fed on
what seems to be best adapted for them ; the drones receive
another kind ; while the future queens live on a specially prepared
product, or " royal food," supposed to be much richer in nitroge-
nous materials. When the larvae are full-grown, the cells are
capped and the pupae form in^^ide of them. In due time the
adults issue, either drones or workers. In the former case they
idle about, doing nothing, except to find food for themselves. In
the latter case they at once assume their full share of the duties
of the hive, gathering honey or pollen, or attending to whatever
else is to be done. Of course, by this continuous increase the
hive soon becomes overcrowded, and then the question arises, Is
the colony in condition to stand a swarm ? If the store combs
are tolerably well supplied, and everything is running smoothly,
the question is decided in the affirmative, and arrangements are
made to have a portion of the inhabitants leave it. Meanwhile
the queen larvae have continued to develop, and are now ready
to assume the adult form. When this period arrives, the ruler
of the hive becomes uneasy, and does her best to get at the
queen cells to kill her maturing rivals. If the workers have
decided that they need a s\varm, she is kept from doing mischief
and they simply block her way. When the new females have
issued, every effort is made to prevent a meeting between the
young and old, or even between the young queens, if there is
more than one. With the new queen or queens fully developed,
and a larger number of workers than can be readily accommo-
dated, the members of the hive become uneasy, cease work, and,
from the noise, appear to be holding a caucus, which finally
results in a considerable proportion leaving the hive under the
leadership of either the old or one of the new queens. This is a
" swarm," and it flies a longer or shorter distance before it settles
in a solid mass, usually surrounding the queen. If the swarm
is not hived at once, the bees sooner or later find a hollow tree
or other cavity, where they start a colony ; but if the insects are
under the care of a proper keeper, the indications are noted, and
.when the swarm leaves the hive it is induced to alight near by,

4i6 ^^ ECONOMIC ENTOMOLOGY.

either through a jet or spray of water directed upon it, or by-
beating tin pans or making some other noise. When the swarm
has settled, the bees can be shaken into a receptacle, and if the
queen is contained in the mass, as she usually is, they make
themselves at home readily in any hive to which they may be
transferred, especially if it contains a small supply of food or a
piece of comb, full or empty. Work is then started at once, and
the colony is soon in full swing. From a sound colony there may
be several swarms in the course of a season ; but if times have been
bad and the bees have not increased sufficiently to warrant it,
there is no swarming, and nothing is placed in the way of the old
queen to prevent her from killing her immature rivals, unless,
indeed, the bees decide that she is worn out and incapable of
supplying a sufficient quantity of eggs, in which case they permit
one or more young queens to come to maturity and let them
fight it out. The victress remains queen of the hive, and if it is
the young female, the inhabitants transfer their allegiance to her
without question, and serve her as faithfully as they did their
original ruler. If by any chance the bees lose their queen, and
have no royal larvae, they take worker eggs or very young
larvae, and by proper care and feeding make queens of them :
royalty in this case being a mere matter of diet.

As to the practical part of bee-keeping, and the details neces-
sary, there are many books especially written to give that infor-
mation, and it forms no part of the purpose of the present treatise.
The object here has been to give merely a sufficient insight into
the working of the hive to indicate the use that is made of the
pollen and its importance in the economy of bee life. It is the
necessity of having food for the larvae that keeps the insects
constantly at work and makes them so effective as poUenizers.
Visiting, as they must do, a great number of flowers to obtain
sufficient pollen for a load, they call at many trees, often far
apart and of different varieties, securing the cross-pollination so
necessary to many plants. They usually visit one kind of flower
only, and I have tested several specimens by microscopic investi-
gation, finding always one form of pollen only.

Bumble-bees have been already mentioned, and resemble in
their economy somewhat the hive-bee, save that here, as in the
wasps, the colony, excepting only the fully developed females,

THE INSECT WORLD.

417

dies each year. We see early in the spring, when the fruit-
trees are in bloom, many specimens droning about on the
flowers, but often also along road -sides, especially where there is
a declivity ; or in fields where there are a few rocks, or where
there are holes in the ground. There we often notice an indi-
vidual buzzing over one spot for several minutes at a time,
apparently subjecting it to the closest kind of examination. This
is indeed what the insect is doing : she is seeking a place to
start a home. This she finds in an abandoned mouse-hole, or
other cavity in the ground, and here begins her nest, lining it
with moss, with fragments of leaves or grass, or with whatever
may be most convenient. Then she gathers a mass of pollen,
upon which a number of eggs are laid. No comb is built ; but the
larvae, when they hatch, burrow into the pollen mass, to which the
mother adds constantly as necessity requires. When full-grown
each forms a smooth cavity, which it lines with a silken cocoon
and changes to a pupa. The cocoon is strengthened from the
outside by the mother, with wax, and in due time we have a little
brood of worker ' ' bumbles' ' resembling their parent in all except
size and the incomplete sexual development. Not until after mid-
summer does the queen, reinforced by the workers which she has
raised, lay eggs that produce males and females, and these are fed
upon food gathered by the workers. The old female dies when the
new brood of sexually complete individuals has hatched. The
latter mate, and the workers and males also die on the approach of
cold weather, leaving only the now impregnated females to survive.
Taken altogether, the order Hymenoptera contains insects that
are decidedly beneficial to the farmer. The first series only, to
which the "saw-flies" and the "borers" belong, are injurious,
and these may always be recognized by the fact that the abdomen
joins the thorax by its whole width, instead of being fastened
simply by a stalk or petiole. Of course, the ants are sometimes
troublesome and indirectly injurious, but, as a whole, the species
are so overwhelmingly beneficial that the order deserves to be
encouraged in every way possible. Bees, wasps, and hornets
are particularly desirable inhabitants of a locality, and in a quiet
way do much to destroy injurious insects, — as much, perhaps, as
the parasites which also belong to the order ; while the bees of all
kinds are simply indispensable to the fruit-grower as poUenizers.

27

PART III.

INSECTICIDES, PREVENTIVES, AND
MACHINERY.

CHAPTER I.

PREDACEOUS INSECTS, PARASITES, AND FUNGOUS DISEASES.

It has appeared throughout this book that, while we have a
great many insects that are feeders upon vegetation, there are
also a great number that are predaceous upon the herbivorous
forms, and yet many others that are parasites, living upon or
within others of the same class. It is a tempting proposition
that we may, perhaps, be able to array the forces of nature
against each other ; that we may keep predaceous forms, and set
them free at the proper season to feed upon those injurious to
farm crops. I say it is a tempting proposition, and it looks
feasible, but that it should be successful involves a great deal
more than is apparent at first glance. In the course of the ages
through which this world has existed there has been gradually
established, by the influence of surroundings, a certain ratio be-
tween all existing life, vegetable and animal. There is a struggle
among the plants themselves as to which shall keep the ground,
and upon the plants feed animals, including insects, which form
a factor in determining the relative abundance of the different
species. With the development of the plants their enemies also
have developed, and always in proportion to the amount of injury
that the plant can stand. That this must be so is evidenced by
the fact that the plants exist at all. One of nature's ways of pre-
venting the plant-feeding insects — for we will confine our re-
marks to insects from this point on — from obtaining control of
and exterminating the plants is to provide enemies of various
418

IXSECTICIDES, PREVENTIVES, AM) MACHINERY. 419

kinds for them. These enemies in turn must be checked, that
they may not exterminate the species they themselves feed upon.
Thus there has been established, gradually and naturally, an
elaborate system of checks and counterchecks, by means of
which a certain proportion is maintained year in and year out
between i)redaceous, parasitic, and plant feeding insects. Under
perfectly natural conditions this ratio does not change much from
year to year, and there is no preference on the part of nature for
one class as against any other. Any interference with this estab-
lished course is almost certain to be disadvantageous in some
directions, and man, in his dealings with natural conditions, has
persistently created for himself a series of troubles arising from
his own acts. By planting large areas of one crop, he has fa-
vored the increase of the insects feeding upon that crop. By cul-
tivating the land, keeping it cleared of rubbish, stones, sticks,
and the like, he has destroyed the shelter needed by predaceous
insects, and the result is that he has in two ways given those in-
sects, which he now calls injurious, an advantage. The conse-
quences, of course, are against him ; and so long as these condi-
tions continue, favoring one class at the expense of another, man
must suffer, unless he himself fulfils the functions previously as-
signed to the predaceous forms. True parasites have not been
so much influenced by his actions, and the species, perhaps,
suffer as much from them as they ever did ; but the natural
checks in operation against the parasites also continue, and
while, perhaps, they have increased somewhat in number, they
have not been able to make up for the loss of the predaceous in-
sects. Furthermore, the feeders upon vegetation suffered also
from the attacks of insectivorous animals, like toads, frogs, and
snakes among the reptiles, and many small animals and birds,
which now also find life insupportable among the artificial condi-
tions. The result is that there has been an actual increase in the
number of specimens of injurious insects, and their parasites bear
somewhat less than their original ratio to them, — that is, each
year a certain proportion or percentage of a brood is destroyed
by its parasites, and this percentage it is beyond our present
power to change to our advantage. In other words, the farmer
cannot, except in isolated instances, count upon parasites or
natural enemies of any kind to keep down injurious insects.

420 ^^ ECONOMIC ENTOMOLOGY.

Even though in each year a certain species may be, in the long
run, controlled by its parasite, this does not necessarily help the
farmer. Let us take, for instance, the cut-worms that are so
abundant each year. If we gather from an infested field two or
three hundred specimens, we find that anywhere from fifty to
seventy-five per cent, of them are parasitized. This looks like a
huge destruction ; but when we consider that the parasites do
not as a rule, affect the larvae until they have done all their
feeding, what benefit has the farmer derived? What difference
does it make whether the cut-worm that destroys his plants is
parasitized or not? At the end of the season we may note that
twenty-five per cent, only of the cut-worms develop into moths :
half of those may be males, and the remainder are females which
will each lay anywhere from three to five hundred and some-
times more than one thousand eggs ; amply sufiicient to pro-
duce in the next brood fully as many caterpillars as existed in
the beginning ! Let us further take the case of the cranberry
Teras\s an illustration. The first brood, early in the season,
has scarcely any parasites ; the second brood, in mid-summer,
is parasitized to the extent of nearly fifty per cent. ; while from
the third brood, in the fall, we get fully seventy-five per cent,
of parasites to twenty-five per cent, of moths. Yet, notwith-
standing this enormous increase of the parasites in the course
of the season, some combination of circumstances destroys so
many of them during the winter that in the spring following
the first brood is again almost free from attack ; and thus it
goes, year after year. The action of the parasite is only to keep
its host within a certain fairly well defined limit, and if that
limit is at a point where the host becomes injurious to the farmer,
he must himself take a hand in its destruction to derive any
benefit. I do not mean, in anything I say here, to lessen the
claims of parasitic and predaceous insects to our consideration.
They have an extremely important function in nature, and with-
out them there would be no possibility of an existing vegetation.
But, on the other hand, it is just as certain that unless there was
some check imposed upon the mukiplication of parasites, etc.,
they would in a short time destroy the insects that they feed
upon, and the destruction of their host would, logically, carry
with it their own destruction. Nature never works in that way :

INSECTICIDES, PREVENTIVES, AND MACHINERY. 421

lier effort is always to give all her creatures an equal chance to
exist.

Man has I'urther disturbed the natural conditions by introducing
into new countries insects that have become ada[)ted to the sur-
roundings in others. Sometimes an insect so introduced does
not find the new circumstances to its liking ; but, on the other
hand, it may find them very much better than those under which
it was originally developed. In such cases we get a multiplica-
tion out of all proportion to the normal habit of the species, and
there may be such a thing as the destruction of the plants that
they feed upon. Let us take, for instance, the elm-leaf beetle,
introduced into this country many years ago, and apparently
without natural enemies suitable for its control. The circum-
stances which it finds here are so much to its liking that, if
allowed to increase unchecked by the efforts of man, it may in
the course of time destroy all the European elms in the regions
infested by it !

The whole object is to show that, since man has introduced
artificial conditions, he must bear the burden of the change
caused by them ; and if this means that there are certain injurious
insects feeding upon the plants he wishes to grow for his own
benefit, he must replace by his own efforts those natural checks
which he has removed by the artificial conditions introduced.
Those efforts on his part consist in the adoption of measures to
prevent increase, or to destroy the injurious insects by means
of poisons or otherwise, and this subject will be considered in
another chapter.

A fascinating theory in connection with this subject is the pos-
sibility of importing parasites or predaceous forms from other
countries for the destruction of pests here. This leaves out of
consideration the fact that it would require a readjustment ol
matters to induce foreign parasites to feed upon American insects,
and it has never been proved that such a .thing is possible within
a reasonable period of time. The case of the Australian Vedalia,
imported to prey upon the fluted scale, Icerya purchasi, is fre-
quently cited as an example of what can be done, but always
without considering the fact that we had an imported insect to
deal with in the first place, which increased abnormally in our
country because of the fact that its enemies were not brought

422

AN ECONOMIC ENTOMOLOGY.

in with it. When this Australian insect enemy was introduced,
it found nothing that it recognized except the Icerya, and, in
consequence, devoted itself entirely to that species, totally sup-
pressing it in a short time. All that was done here was to re-
store the balance of nature, because the scale insect is a tolerably
rare species in Australia, owing to the number of its enemies.
Nothing can be argued from this case as to the possibility of in-
troducing foreign species to control strictly American pests with
which they are not acquainted. An effort was made in this
direction in Virginia, the object being to import European enemies
of bark-borers to check the invasion which seemed to threaten
the forests of that State. The utmost that can be said for the
experiment is that the imported insects have not quite died out,
and that occasionally one is seen out of many hundreds brought
in. But, on the other hand, the invasion which they were im-
ported to check has been disposed of by nature herself, an
unusually severe winter destroying the pests so completely that,
instead of being abnormally abundant, they have become almost
rarities. We can frequently do good where we have imported
insects, or insects occurring also in other countries, by finding
and introducing their parasites ; but it seems rather an Utopian
scheme to train predaceous insects of other countries to feed upon
our native species with which they are not acquainted.

The subject of fungous or contagious diseases of insects is an
interesting one, but which must be dismissed here with a brief
reference only. We know that insects often suffer from disease,
and that epidemics sometimes occur among them, destroying
myriads. Some of these diseases have been studied, and elab-
orate attempts have been made, chiefly in Kansas and Illinois,
to make use of them practically. The chinch-bug has been the
insect most experimented upon ; and while it has been demon-
strated that it is possible to cultivate the disease and to infect pre-
viously healthy bugs with it, it has also developed that the
disease demands certain definite conditions of climate and
atmosphere for its own propagation. Thus, dry, warm weather
is unfavorable for the growth of the disease, while it favors the
multiplication of the bugs ; but moist or wet weather, which re-
tards development in the bugs, favors the disease. Until we can
control climatic conditions, or otherwise secure the intelligent

INSECTICIDES, PREVENTIVES, AND MACHINERY. 423

co-operation of the weather, our results are Hkely to be uncertain.
Nevertheless, there may be great possibilities in this direction,
and in the minute organisms requiring a powerful microscope to
make them even visible we may yet find our most effective help
in checking- destruction by insects.

CHAPTER II.

FARM PRACTICE TO PREVENT INSECT ATTACK,

Throughout this work reference has been frequently made
to methods of ordinary farm practice for preventing insect attack.
It is desirable to look a little closely into this subject, and to
detail somewhat the methods that may be resorted to with good
effect. Prevention is always better than cure, and very frequently
serious injury may be averted by doing ordinary farm work at
just the right time, or in exercising care in the selection of fer-
tilizers or in the rotation of crops.

Far above everything else is cleanliness on the farm, and this
term is to be construed as strictly as possible. Cleanliness means
clean " culture ; the destruction of weeds ; the removal of crop
remnants as soon as the crop is done ; picking up and destroy-
ing dropped fruit in orchards ; removing, burning up, or other-
wise destroying all rubbish that cumbers the ground in winter ;
keeping buildings painted or whitewashed in good shape. Allow
no rubbish, weeds, or shrubbery to grow among the fences, and
in all other respects leave the farm as nearly bare as possible
of everything save what strictly belongs there. The object of all
this is to do away with possible hiding-places for insects during
the winter, and to prevent their reaching maturity during the
summer. A large proportion of insects live through the winter
in the adult stage, or in the partly grown condition, and a great
many of them hide under rubbish. Sometimes they get just a
short distance below the surface of the ground among the roots ;
sometimes they crawl into crevices of fences, of logs, or of boards,
— wherever, in fact, there is the least opening for them to get

424

A^V ECO.YOMIC ENTOMOLOGY.

into. A tree with rough bark, covered with moss, Hcheus or
other unnecessary growth, often harbors hundreds of specimens,
and one object of the farmer should be to destroy all hiding-
places that may be of service to the insects for winter-quarters.
Therefore, if possible, all fences should be whitewashed, as well
as all out-buildings. Insects do not like lime, and where a dozen
specimens may be found on a plain board fence, scarcely one
will venture on one that is limed. This kind of campaign is
especially effective against certain forms of plant-bugs, a large
proportion of which live through the winter in the half-grown or
adult condition. Offer them a bare soil wherever that is agricul-
turally feasible, and at all events never give them the opportunity
of hibernating in a weedy field — one that has been allowed to
grow up after harvest with the idea that it is to be turned under
in the spring. Such fields are veritable nurseries for insect pests.

It frequently happens that a farmer is through with a crop
before the plants stop growing, and occasionally they remain in
the field weeks after they have ceased to be of any practical use.
During all this time the insects peculiar to that crop are multi-
plying, coming to maturity undisturbed, and providing for their
increase during the ensuing year. For instance, with cabbages :
if, after the heads are taken out, the butts and outer leaves are left
in the ground, the cabbage-lice will there increase and prepare
for the winter. If the butts are taken out and fed up, or destroyed
in any other satisfactory manner, it will put an immediate stop
to their development ; and if the practice is continued systemati-
cally, and cruciferous weeds are also kept down on the farm,
cabbage-lice will soon become so reduced in number as to be
practically harmless. So, from melon vines only a portion of
the crop is often gathered, and they are then left to grow and
decay naturally upon the ground. The vines may be infested by
borers, or they may harbor squash-bugs, or melon-lice, or a
number of other pests. By removing and destroying as soon as
there is no further use for them, a period is at once put to the
increase of these insects. They will be compelled to look else-
where for food or will starve to death.

In corn-fields, leaving the roots and stumps in the ground
throughout the winter offers a premium for the increase of insects
that depredate upon this crop. Such pests as "corn-worms"

INSECTICIDES, PREVENTIVES, AND MACHINERV. 425

can be easily kept in check by fall ploughing and burning the
butts and roots, and a good effect will also be produced as against
the corn-root-louse and similar pests. Instances might easily be
multiplied without adding to the force of the suggestion that the
ground should be kept as free as possible from all growth that
might afford lodgement or shelter for insects.

Another important operation which can be made use of is
ploughing at the proper time, and, among other things, fall
ploughing, whenever possible, is to be recommended, especially
of sod land. Many different kinds of insects live in sod, among
them cut-worms and wire-worms, both well-known and important
pests. A great deal can be done in the direction of destroying
these creatures by ploughing the land late in fall. Under the
proper headings will be found the reasons why such an operation
proves beneficial in special cases ; but in general we can say that,
by disturbing the land after the insects have prepared for their
winter rest, they are exposed to their natural enemies when more
helpless than usual. A great many are then in the pupa state,
absolutely unable to help themselves, and breaking their cells at
that time means death to them. A very large percentage of
reduction in the number of injurious insects can be effected by
this practice alone. I am aware that fall ploughing is inadvisable
on some kinds of land, but it is directly beneficial on others. It
is a measure that must be used with judgment, and each farmer
should know enough about his own land to decide whether or not
fall ploughing is advisable. I distinctly recommend it wherever
it is possible. As a rule, where the ground is to remain bare,
the ploughing should be done as late in the season as possible,
that the insects may not be able to re-establish themselves ; for
instance, when the corn-root-louse is the object of the attack,
early ploughing allows the ants that shelter them to construct
new galleries and gather in their belongings to safe shelter, while
very late ploughing makes it impossible for the ants to work, so
that they and the lice both perish : the latter almost certainly^
The date of ploughing, other than in fall, is sometimes important ;
thus, against the root web- worms in fields after grass, if the sod
is turned very early, before the moths have appeared and laid
their eggs, the crop remains free. If delayed until the sod has
become stocked with eggs, the corn is almost certain to suffer.

426 AN ECONOMIC ENTOMOLOGY.

Sometimes, where land cannot safely be left bare during the
winter, it may be ploughed earlier, and some catch crop, simply
to cover the surface, can be put in, and it matters very little what
this is. It may be crimson clover, rye, wheat, — anything, in
fact, to get a covering, provided it is something radically different
from what was on the ground before the ploughing was done.
Corn-fields should be treated in this way after the crop has been
harvested, if late ploughing is undesirable, for it is always a mis-
take to leave them unturned until the spring following. It is
a good plan, just as soon as one crop is off, to put in some-
thing else, which, as already suggested, should be quite different
in general character ; and this brings up the question of rotation.
It is impossible to make any generally applicable statements on
this subject. No two regions of our country are entirely alike in
their practice, in the crops raised, or in the rotation adopted ;
but so far as possible a rotation should be selected which will
keep the ground covered all the time, the crops that follow each
other being unlike in their natural family, — that is, grass should
not follow wheat or rye, if it can be avoided ; nor should potatoes
be followed by egg-plants or tomatoes ; or cabbages by mus-
tard or radishes ; but in all instances crops as diverse as may be
should follow each other, and as rapidly as possible. Where
wire-worms are the chief sinners, crimson clover may sometimes
be usefully employed. Plant this in fall, and in spring it will be
in excellent condition to attract the adults to lay eggs. Turn it
under late in May or early in June, after cutting for hay or as a
green manure, and plant any suitable crop. The very young
larvae will be incapable of doing injury, and will fail to maintain
themselves under the new conditions. It must be remembered,
however, that this practice will favor cut-worm increase, and
measures must be held in readiness for these when the planted
crop makes its appearance.

Another good plan is to have a considerable number of
chickens, and to train them to follow the plough. This can be
very easily done, and after a few are once trained, they will in
turn teach the entire flock, while the young learn readily from
the older. Chickens following a plough will pick up almost
every insect that is turned up, be it in the larval, pupal, or adult
condition, and they are especially effective in fields infested by

INSECTICIDES, PREVENTIVES, AND MACHINERY. 427

white grubs. Badly infested fields may even be ploughed more
than once, and in different directions, just to give the chickens
an opportunity of picking up the insects. I have seen flocks so
well trained that whenever the plough harness was put upon the
horse they gathered together, waiting until he was taken to the
field.

Turkeys are exceedingly useful where grasshoppers are to be
dealt with, because they are especially fond of these insects ; and
for the same purpose Guinea-fowls are also advisable. Here
again the practical farmer will find, with a little observation, just
about the range of usefulness of the various fowls, and will be
able to adapt his cultivation somewhat to their peculiarities.

In the matter of the fertilizers to be used we have also an oppor-
tunity for careful selection. We may say generally, that manure
and all vegetable matter in a decaying state favors the develop-
ment of insects. It affords both food and lodgement to many
species, and when it is put on in the fall or winter in a coarse
condition, it is a direct benefit to insects that hibernate, even
when ploughed under. On the other hand, the mineral fertil-
izers, especially those containing a considerable percentage of
salt, are unfavorable to insects of all descriptions, and to some
they are deadly. Experience has shown that plant-lice are sus-
ceptible to the action af the salty fertilizers, and that cut-worms
and wire-worms are affected by them to a considerable extent.
Among corn insects, injury from the root web-worms may be
entirely avoided by using the mineral fertilizers instead of barn-
yard manure, if fall or very early spring ploughing is not feasible.
So the time of application is important, as is the amount to be
applied. For instance, in land infested by wire-worms and to be
put into corn, the best time for the application is just after it has
been prepared and after the seed has been planted. Then all
the potash should be put on, in the form of kainit, in one appli-
cation, while as much as is desirable of the nitrogen should be
put on in the form of nitrate of soda. In this way the soil
becomes impregnated with a rather concentrated salty mixture
which is fatal to many of the insects. The same amount of fer-
tilizer distributed in several applications, or put on the ground in
fall, or when vegetation covers it, would be entirely ineffective.
Mineral fertilizers are advisable wherever their use is otherwise

428 A A' ECONOMIC ENTOMOLOGY.

profitable, and are always to be preferred to decomposing vege-
table matter, from the insect stand-point. The details of the
applications to be made are found where the insects themselves
are treated. Where barn-yard manure must be used, it is always
a good plan to mix it with air-slacked lime, land plaster, or kainit,
and this can be done as fast as it is made in the stable. It will
add to its value, will hold the ammonia, and will make the mixture
an undesirable one for insects to live in.

Grass land may be kept tolerably free from undesirable pests
infesting the roots by using as fertilizer a mixture of one hun-
dred bushels of lime and one ton of kainit slaked together. This
may be applied in the spring, and will act as a stimulant as well
as destroy many of the insects inhabiting the soil.

There are yet other ways in which we can head off insects ; for
instance, in the selection of the time of planting. It happens
frequently that insects make their appearance at a very definite
time, and in the ordinary course of nature have only a few days
within which they must lay their eggs and provide for the con-
tinuance of their kind. If they do not find the cultivated food-
plant, they are compelled to make use of some substitute wild
plant, on which they do not thrive as well ; or they may not be
able to oviposit at all, and a large proportion will perish without
being able to reproduce their kind.

When the life history of a seriously injurious insect is known,
it will often pay to adapt our farm practice so as to prevent injury.
For instance, experience has proved that the Hessian-fly appears,
ready to lay eggs for a late fall brood, during the early days of
September. By delaying planting until after the middle of that
month, or even later where the latitude makes this feasible, the
insects are compelled to lay their eggs in grasses other than
wheat, or in the volunteer grain that they find in fields or along
the roads.

Cranberry growers take advantage of their knowledge of the
life history of the Teras infesting that crop by keeping the bogs
covered with water until after the middle of May, thus compelling
the moths to lay their eggs on other plants belonging to the same
natural family.

In a similar way we can sometimes induce the insects to ovi-
posit in a trap crop planted especially to attract them and pro-

INSECTICIDES, PREVEXTIIES, AXD MACinXERY. ^zQ

tcct the staple. An example of this is the practice of certain
squash growers, w ho plant early summer squashes to attract the
borers, and Hubbards and marrowfats rather late, so as to be
unattractive to the moths as compared with the vigorous early
plants. The summer varieties may be taken out and destroyed,
with all their contents of borers, after an early crop has been
picked from them, and this will leave the later varieties free,
while it also accomplishes the destruction of an entire brood of
larva. So it has been found practicable in the South to protect
cabbages from the attacks of the harlequin cabbage-bug by
planting an early trap crop of mustard, to which the insects are
attracted, and from which they can be gathered by hand or
destroyed by spraying with pure kerosene.

An instance of the use of methods of cultivation we find in the
practice of blackberry growers, who, to prevent injury from the
red-necked canc-borer, cut off during the latter part of June all
the shoots then above ground, and either gather and destroy, or
merely allow them to wilt and die. The beetles have all disap-
peared at this time and all their eggs are in these shoots. The
new canes that come up after this trimming become sufficiently
mature and are in sufficient number to make next year's crop,
while they are free from any possible beetle attack.

There are many other wavs in which farm practice may prevent
injury from insects, and to the intelligent farmer these methods
will commend themselves much more than the indiscriminate use
of insecticides after damage has been caused. The prevention of
attack is always better than the destruction of the insects after
injury has been accomplished, and some of these methods have
the advantage of effecting a permanent reduction of the injurious
species. Further details are hardly in place here, but what has
been said will explain the reason for many of the recommenda-
tions made in the body of the work.

430 AN ECONOMIC ENTOMOLOGY,

CHAPTER III.

PREVENTIVES.

There are many insects seriously injurious to trees that are
difficult to reach with insecticides of any kind, and are with diffi-
culty destroyed in any way, and first among these are borers,
whatever the order to which they belong. It has been already
indicated under various headings what measures are available for
preventing and curing injury, but perhaps a grouping of what
may be termed preventive measures will be of some use. It is
the fruit grower that suffers most from boring insects, and while
small fruits are often attacked, the most serious and permanent
injury is done to trees. Peach-trees are girdled at or near the
surface of the ground by a Lepidopterous borer ; apple, pear,
quince, and similar trees are attacked on almost all parts of the
trunk, yet preferably near the base, by Coleopterous borers, and
almost all our fruit-trees are subject to the attack of bark-beetles.
Many of our shade-trees also suffer from boring insects of various
descriptions. It is often easier to keep these borers out than it
is to destroy them after they once get in, and to do that we must
resort to mechanical measures. The simplest as well as most
effective method is the use of a wire mosquito netting on apple,
quince, and similar trees. The parents of both the round and
flat-headed borers infesting these trees are quite large insects, un-
able to oviposit or lay their eggs through the meshes of an ordi-
nary mosquito netting, provided it be kept at least half an inch
from the bark at all points. In this way apple-orchards and those
subject to the same kind of injury may be effectively protected,
and trees once netted will need little attention, except an occasional
retying, for several years. The wire netting should, ot course,
be thoroughly painted in the first place, and should have suffi-
cient lap, when cut, to allow of considerable growth of the tree.
The top must be closed by being tied tightly to the trunk, or the
interval between the trunk and netting must be filled with cot-
ton or some similar material, that the insects cannot crawl under
it. In like manner the ground must be hilled around the wiring

INSECTICIDES, rRElEXTIVES, AND MACHINERY. 431

at the base, to prevent the entrance of insects at that point. If
it should happen that trees are already infested, the beetles that
come from the trunk will be unable to get away and should be
killed through the netting.

Wrapping with newspapers or tarred paper is another satis-
factory and tolerably effective measure. Newspapers will last a
season without being renewed ; tarred paper may last longer, but
will need retying. The tar adds nothing to the effectiveness of
the paper, but serves to protect it and make it more lasting. The
covering must be complete, so that the insects cannot get be-
neath it. Here also any insects already in the trunk of the tree
will be kept in and perish. This is applicable to all insects, what-
ever the size, and will prove effective in proportion to the care
used in fastening the paper in place.

Instead of these materials, the German raupenleim or the
American dendrolene may be applied. Both are crude petro-
leum products, and are in the nature of an impure vaseline, more
or less greasy, smooth, of a butter-like consistency at ordinary
temperatures, and absolutely resisting wash by rains. Applied
three-sixteenths of an inch thick or more to the surface of the tree
to be protected, they will last an entire season without" renewal.
The raupenleim hardens, after a time, into a crust, while the
dendrolene tends rather to become absorbed. No insect will
rest upon these materials long enough to lay an ^%%, and no larva
can bore through them to reach the trunk ; hence one thorough
application is an effective protection against borers of all kinds,
bark-beetles as well as others. As against the smaller species,
the materials answer to destroy the borers already in the tree by
preventing them from coming out through the bark. Applied
around the base of peach-trees, borers may be kept out, and, of
course, no scale insect can set where they are used. Like all
other mechanical protections, they are effective in proportion as
they form a complete covering to the bark, and probably in no
other way.

Either raupenleim or dendrolene, particularly the latter, is
effective in preventing injury by canker-worms or other insects
that crawl up the trunk to reach the leaves, whether in the moth
state to oviposit or in the caterpillar state to feed. A broad band
of dendrolene, put on early in the spring, will absolutely pre-

432 AX ECONOMIC ENTOMOLOGY.

vent injury by canker-worms, because it hinders the female from
reaching the branches to lay her eggs. In the same way, trees
cleared during the winter of the ^^^ masses of the vaporer moth
or of the sacs of the bag-worm may be kept cleared during the
year following by a band of these materials. It is said that
raupenleim, under the influence of cold nights, becomes too
hard to be effective, but this is not the case with dendrolene.

A word of caution must be added. Both of these materials
penetrate to some extent, the dendrolene more than the rau-
penleim, because it never becomes hard and never dries. On
thin-barked or very young trees, if it is left on continuously,
it will not only check the growth of the bark and kill the
outer layer, but may destroy the tree itself. This is especially
true of peach-trees, and on such the materials should not be
applied very heavily, and should be washed off after midsum-
mer with some potash wash. Both raupenleim and dendrolene
dissolve readily in benzine, turpentine, or kerosene, and they
combine easily with any caustic ; hence the bark can be cleared
without very much trouble after the danger season is over. On
old trees, where the outer layer of bark is no longer active, less
danger is to be apprehended. Where trees are banded against
the canker worm or similar insects, the easiest way would be to
first tack a band of heavy wrapping-paper close to the trunk and
apply the material to that. It should be smeared over the edges
of the paper to the bark, so as to prevent any insect from getting
under it, and when the danger season is over this band can be
cut away without trouble, leaving only a narrow ring of the
smear, which could do no harm. Where protection against
borers only is sought, all injury can be avoided by mixing
the dendrolene with dry earth or with land plaster, weight for
weight, which will not reduce its value as a covering, but will
diminish its penetrating qualities.

Lime is an exceedingly good preventive, applied in the form
of whitewash. Fruit-trees that have the trunks whitewashed
early in spring will be apt to remain measurably free from scale
attack, and if it is applied fresh, a great many of the scales already
upon the trunk will be killed. It is an advisable thing, when
Bordeaux mixture is applied, to use plenty of lime, especially
upon the trunks and branches of the trees, because no scale in-

INSECTICIDES, PKEVEXTIVES, AND MACHINERY. 433

sect can or will set on a lime-covered surface. Of course, lime
washes away readily, and must be renewed from time to time to be
thoroui;hly effective. Keeping it up until midsummer, however,
is usually sufficient, except against scales that have several broods.

Under the heading of "preventive measures," keeping the
trees clean, free from all sorts of abnormal growth and from loose
bark, liiay be counted. Winter washing the trunks with a strong
potash solution is always advisable. This cuts away anything in
the form of fungus, moss or lichen growths, and leaves the bark
fresh and glossy for the season following. It also destroys
many of the insects hibernating upon the trunk in any stage.

Finally, the most important of all preventive measures is good
farming. Keep crops of all kinds in the most vigorous possible
condition, with plenty of readily available plant food, and in
orchards allow no dead wood of any kind to remain over winter.
Dead or dying branches should be cut, carted out, and burnt
before the first warm spell of spring, and dying trees should meet
the same fate. There will then be nothing to encourage insects
either to come into the orchard or to remain there if accidentally
brought in. Good farming, it may again be said, is the very best
possible preventive of insect injury.

It is necessary to merely mention that printer's ink, birdlime,
and perhaps other substances have been recommended for band-
ing trees, or for the purposes for which raupenleim and den-
drolene have been recommended. Hydraulic cement or " water
lime" mixed with skim-milk, to form a thick paint, makes a
covering that will last an entire season.

To prevent climbing cut worms, canker-worms, or similar
creatures from ascending a tree, a band of cotton batting can be
satisfactorily used in many cases as follows : Make the band from
eight to twelve inches wide and long enough to go round the
trunk and lap two inches. Tie tightly at the bottom of the band,
smooth side, if any, to the trunk, and then turn down the band
from the top, like an inverted funnel. This prevents the inner
side of the funnel from matting when wet by rains, and under
ordinary circumstances forms a complet.'^ bar to the ascent of
insects. A band of this kind above a coating of some kind, to
prevent the bark from being eaten, ought to protect even very
voung orchards from climbing cut-worms.

2S

434 AN ECONOMIC ENTOMOLOGY.

CHAPTER IV.

INSECTICIDES.

Some of the principles governing the apphcation of insecticides
have been referred to and stated in previous parts of this work,
but it is deemed advisable to refer specifically to the different
kinds of materials, and to mention the range of the most useful
among those now upon the market. Broadly speaking, we may
say that insecticides are of two kinds, — those that kill by being
eaten, or stomach poisons, and those that kill by contact. Some
substances, such as hellebore and tobacco, belong to both cate-
gories,— that is to say, they are poisonous when eaten, and,
when properly applied, also kill by contact.

Oi the stomach poisons, none are in more general use or of
greater importance than the preparations of arsenic, and of these
three only need be considered here, — Paris green, or arsenite of
copper, London purple, or arsenite of lime, and "gypsine," or
arsenate of lead. All of these have very much the same range
of usefulness, and may be treated together. In each case the
active principle is arsenic, and the combination with the other
material is simply to put it into an insoluble form to prevent
injury to the plants ; for arsenic is quite as violent a poison to
plants as it is to animals. In Paris green the arsenic is in combi-
nation with copper, and in many cases we get, besides the in-
secticide effect, a direct influence upon fungi. An average good
sample contains about as follows :

Per Cent.

Moisture 74

Arsenious oxide (AsgOg) 68.82

Copper oxide (CuO) 30.59

100.15

A small quantity of the arsenic remains here in a soluble con-
dition, especially when the weather is warm ; hence we frequently
find that spraying on a hot day is much more likely to burn the
foliage than when done on a cool day, or late in the afternoon.

IXSECTICIDES, PKEVEXTIVES, AXD MACJILYEKY. 435

This is due entirely to the fact that the water appHed to the leaves
becomes rapidly warmed up by the sun before evaporating, and
meanwhile dissolves every particle of soluble arsenic, bringing it
into direct contact with the vegetable surface upon which it rests.
In London purple we have a decidedly smaller percentage of
arsenic, as will be seen by the following analysis :

Per Cent.

Moisture 3.27

Arsenious oxide (AsgOg) 41 -44

Lime (CaO) 24.32

Iron and alumina (FegOaT AI2O3) 3.37

Sulphuric acid (SO3) 31

Dye, by difference 27.29

100.00

More of the arsenic is soluble here, which explains why London
purple is more apt to burn foliage than Paris green. Both the
insecticides just mentioned can be made entirely harmless to
foliage by adding weight for weight of caustic lime when mixing.
That is to say, in preparing the poison for use, take one pound
of Paris green or of London purple and one pound of quick-
lime ; add water enough to slake the lime, and mix thoroughly
while hot, so as to incorporate lime and poison completely. This
will fix with the lime every particle of the soluble arsenic con-
tained in the mixture, and it can then be diluted with water and
applied at almost any reasonable strength without much danger
of injury to even the most tender foliage.

Paris green, containing the greatest percentage of arsenic, will
go furthest for insecticide purposes, and for most insects will be
effective when applied in liquid form at the rate of one pound in
two hundred gallons of water. Used against the plum curculio,
or against the codling-moth, one pound in one hundred and
seventy-five gallons is more effective. Used against the potato-
beetle, one pound in one hundred gallons is most satisfactory.
Used in a dry condition, the Paris green may be applied without
any danger of injury, provided the application be made in a very
fine dust. It can be mixed with plaster of Paris, flour, or air-
slaked lime, and, practically, one pound of Paris green in one
hundred pounds of lime or plaster makes a good mixture, effec-
tive for insects of almost all kinds and harmless to plants. There

436 AN ECOXOMIC EXTOMOLOGY.

are some instances when the dry apphcation is to "be preferred
to the spray, as in the cotton-field against the cotton-worm and
against potato-beetles. The essential points in powder applica-
tions, where the substance is to be used undiluted, is to have it
perfectly dry, and to put it on very thinly and evenly. Paris
green, to have the greatest effect, should be extremely fine ; the
finer the particles the more effective will be the application and
the greater the surface covered by an equal amount of poison.
Where used in water it remains in suspension better in propor-
tion as the material is in good mechanical shape ; the larger the
grains the more rapidly they sink to the bottom. In applying
Paris green it must always be remembered that there is no solu-
tion, but merely a mechanical mixture ; that the substance is
heavy and will sink to the bottom unless it be kept constantly
stirred.

London purple is a waste product, and its composition is not
in all cases quite the same, but under ordinary circumstances
does not vary much from the analysis given. It should always
be mixed with lime, as already described, before being used. It
is effective against most insects at the rate of one pound in one
hundred and eighty gallons of water. Against the plum curculio
or the codling-moth, one pound in one hundred and fifty gallons
of water is more effective ; while against the potato-beetle, one
pound in one hundred gallons is generally satisfactory. London
purple can also be used dry, but should never be used pure in this
way, because even a small degree of moisture may have the effect
of liberating some of the free arsenic and causing injury. It is
best combined with air-slaked or dry hydrate of lime, and is
then both effective and harmless. The material is very much
finer and lighter than Paris green, and remains in suspension in
water very much better ; therefore, less stirring is required ; but
all the other points that have been referred to under Paris green
apply here equally well.

Arsenate of lead, or "gypsine," stands on a different footing,
yet acts in the same way. This must be made, as used, of arse-
nate of soda four ounces and acetate of lead eleven ounces, or
in that proportion for a larger or smaller quantity. These sub-
stances dissolve readily, and the quantities given can be mixed
in one gallon of water for dilution, or can be placed in one

INSECTICIDES, PKEVEX'JHES, AND MACHINERY. 437

hundred gallons ready for use. This combination has the ad-
vantage of being harmless to foliage, whatever the strength in
which it is applied. The fifteen ounces of mixed arsenate and
acetate have been apjjlied to peach-trees in two gallons of water,
antl this — the most delicate and sensitive of all fruit-foliage —
was absolutely uninjured. The mixture is less poisonous than
either Paris green or London purple, containing, as it does, a
smaller percentage of arsenic in an absolutely insoluble form ;
but it is also much cheaper, and to obtain the same effects costs
just about the same, or a trifle less. As a rule, four ounces of
arsenate of soda and eleven ounces of acetate of lead will suffice
for one hundred gallons of water, and this mixture will be effec-
tive against most insects, including the elm-leaf-beetle in all its
stages, the various web-worms, canker-worms, and the codling-
moth. Where a rapid effect is necessary, the quantity can be
doubled. Where a great deal of the mixture is to be used, it
can be made in a concentrated form, and a proper proportion of
the stock added to each tank of water as used. Arsenate of
lead does not dry, but forms an almost pure white, pasty pre-
cipitate. It remains well in suspension, and needs but little
stirring. Its great advantage is its harmlessness to plant-life of
all kinds. It should not cost above eight cents per pound for
arsenate of soda and fourteen cents per pound for acetate of
lead, or about thirteen cents per fifteen ounces for the arsenate
of lead.

Pure white arsenic has been recommended, and is used with
satisfaction by some agriculturists. It is certainly the cheapest
as well as the most active of the poisons of this class. It is effec-
tive at the rate of one pound in from two hundred and fifty to
five hundred gallons of water, the latter strength corresponding
to Paris green at one pound in two hundred gallons, and the
former to one pound in one hundred gallons. It contains much
more soluble arsenious acid than either of the other mixtures, and
will burn foliage severely unless mixed with twice its own weight
of quick-lime. If that be done, however, an insoluble arsenite
of lime is obtained which is exceeding effective and can be used
as safely as any of the other mixtures.

There is sometimes a little difficulty in making a water mixture
stick to very smooth, or spread over very hairy leaves, and in

438 AN ECONOMIC ENTOMOLOGY.

such cases the addition of one pound of soap to every forty or
fifty gallons of water will aid matters considerably. The mixture
will spread much more completely, and will adhere even to very
smooth or feathery foliage if a fine spray nozzle is employed.
One quart of molasses or, better, glucose in every fifty gallons
of water will also greatly increase the adhesive and lasting quali-
ties of any mixture employed.

These arsenical poisons act only through the stomach, and no
insects are able to resist them entirely, although some bear a
considerable amount without showing immediate effects. When-
ever they are available, it will pay to use them to the exclusion
of other materials. There is no other stomach poison that com-
pares with them. And here it may be advisable to say a few words
concerning a great many ' ' harmless' ' insecticides placed upon
the market.

As a matter of fact almost all the commercial insecticides other
than pastes or soaps contain arsenic in some form or shape, and
this is in most instances the killing agent. It is also quite true
that under ordinary circumstances the preparations are ' ' harm-
less" to man, because in so diluted a form. As these poisons
are used upon plants, the proportion is so small that danger to
life is not to be anticipated, except as a result of the grossest
carelessness ; hence, strictly speaking, the mixtures are ' ' harm-
less," though containing arsenic. The purchaser, however, usu-
ally pays at least three prices, and, in addition, freight charges
upon a mass of inert diluting matter.

There is another way of using the arsenites which should be
briefly referred to here, — i.e., in a poisoned bran mixture, to
attract cut-worms and some other insects to a deadly feast. Mix
one pound of Paris green, or half as much white arsenic, with
fifty pounds of bran, making the combination as perfect as pos-
sible ; then add water enough to moisten thoroughly, so that the
mixture can be ladled out with a spoon without dripping. A
little sugar or molasses in the water makes the mass rather more
adhesive and lasting, but apparently no more attractive to the
insects. How this mixture should be used will be found stated
in those cases where its employment is indicated.

Bichloride of mercury, or "corrosive sublimate," is an ex-
tremely violent poison, of which some use has been made, but

IXSECTIC/DES, PREVENTIVES, AND MACHINERY. 439

generally with only small satisfaction. It is a deadly poison
and effective against insects, but, unfortunately, is just as injurious
to plants, and the limit of effectiveness as between plants and
insects is so narrow as to render its use undesirable in most cases.
It is valuable only in those few instances where it is desirable to
poison a prepared food or bait, and its use is not advised, except
in special cases where particular directions are given.

The Bordeaux mixture, though primarily a fungicide, has
excellent insecticide qualities in certain cases, and, among others,
it seems to be almost a specific against flea-beetles. This is an
important feature, and renders its use doubly valuable on pota-
toes, egg-plants, tomatoes, and other crops susceptible to flea-
beetle attack. Either Paris green, London purple, or white
arsenic may be added to the Bordeaux mixture where a com-
bined insecticide and fungicide is desired, but Paris green is the
best. London purple only can be added to the ammoniacal
carbonate of copper, since the ammonia in the fungicide acts as
a solvent to the arsenic in Paris green. Either of the fungicides
may be treated as replacing water, in determining the amount of
the insecticide to be used.

The formula for the Bordeaux mixture is as follow's :

Sulphate of copper 6 pounds.

Quick-lime 4 pounds.

Water 22 gallons.

Dissolve the copper sulphate in one gallon of hot waiter, and
in another vessel slake the lime with a gallon of water ; add the
milk of lime slowly to the copper solution, stirring constantly,
and strain through a sieve or coarse gunny sack ; finally, add
twenty gallons of water, and the mixture is ready for use. This
gives the standard full-strength mixture, and half strength or
other proportionate strengths are produced by simply adding
more water.

The ammoniacal solution of copper carbonate, or "cupram,"
is made as follows :

Carbonate of copper 5 ounces.

Ammonia water (twenty-six per cent, strength) . 3 quarts.
Water 30 gallons.

440 AN ECONOMIC ENTOMOLOGY.

Wet up the copper carbonate in a quart of water, add to it the
ammonia, and when completely dissolved and diluted with the
water the compound is ready for use.

Holding a sort of intermediate position between stomach and
contact poisons are powdered white hellebore and tobacco, both
of which may be used pure in the form of either a finely ground
powder or a decoction. Hellebore has a very narrow range of
effectiveness, and is particularly useful only against saw-fly larvae
like the " currant-worm." If used dry, it can be dusted on pure
or mixed with twice its own weight of land plaster or cheap
flour, and will kill by being eaten or by coming into contact with
the insects. If a spray is preferred, it is generally effective within
its range at the rate of one ounce in two quarts of water, and
sometimes, in the case of young saw-fly larvae, one ounce in one
gallon of water will be sufficient. The material should be steeped
in one pint of boiling hot water, and the cold water added grad-
ually. The sediment can be sprayed on with the liquid, or it
can be thrown away and only the extract used. The decoction,
at the rate of two ounces in one gallon of water, has been highly
recommended against the cabbage-maggot, but the reports are
too contradictory to make it advisable to rely upon it for that
purpose.

Tobacco has a very much wider range of usefulness ; few in-
sects care to eat of it, and a plant thoroughly sprayed with a decoc-
tion is safe from the attacks of flea-beetles and a great variety of
other insects. It is as effective against the saw-fly larvae as is
hellebore, and may be applied in much the same way. It may,
in many instances, be applied at the base of plants to keep off
borers and root-feeders generally : for instance, against the cab-
bage-maggot, a handful of tobacco dust at the base of each plant
will usually serve as a tolerably complete protection. It is as a
contact poison that it has the greatest advantages, and it may be
used effectively against plant-lice, either in a dry powder or in
decoction. If used as a powder, it is very important that it
should be as finely ground as possible. All contact poisons kill
through the stigmata, or spiracles. The fine dust makes its way
through the breathing pores into the trachea, and sets up an irri-
tation which results in the death of the insect. The coarse par-
ticles are sifted out by the protective structures with which most

LVSECT/C/DES, PREVENTIVES, AND MACHINERY. 441

insects arc sui)i)lied, but very fine j)articles often make their way
tliroug^i them. It is important, therefore, if tobacco is to be
used dry, that it be in as fine a condition as it is possible to ob-
tain. This ai)pHes even where it is used on the surface of the
ground around cabbage plants. As a decoction its range of
usefulness is greater. It is fatal to a large number of caterpillars
of the smaller moths, both as a contact and as a stomach poison,
and cranberry growers in Massachusetts use great quantities of it,
at the rate of one pound to one gallon of water, against ' ' vine-
worms" and "fire-worms." Stems and other refuse are just as
good as leaf tobacco for this purpose, and the usual method is to
boil down the coarsely chopped stems until a deep brown extract
is obtained. This is also effective against plant-lice. Ground
tobacco may be applied on the surface around trees infested with
root-lice, and the result will be beneficial, especially in light soil.
As against the peach-root lice, tobacco has been employed by
first trenching around the base of a moderately large tree at a
distance of two feet from the trunk, and applying the tobacco
dust in the trench. To obtain the greatest effect there should be
an early application of water, either in the form of rain or arti-
ficially, to dissolve the nicotine and carry it into direct contact
with the root-feeding lice. As tobacco is also a fertilizer, quite
rich in potash, the benefit to the plants is doubled where the
material is applied to the soil. As a stomach poison tobacco is
not often to be recommended, but as a contact poison it is fre-
quently the most cleanly, and is a favorite remedy in the green-
house. Besides the methods already indicated, it may also be used
in the form of smoke ; burning or steaming it, and sending the
impregnated vapor into the conservatory or hot-house. Tobacco-
smoke is quickly fatal to all insects that breathe it, but plants ex-
posed to it for any great length of time are also likely to suffer.
No specific directions as to the quantity of tobacco to be used
can be given, and it will require practical experience to acquire
the knowledge for each case. Good effects can be obtained in
greenhouses by simply placing tobacco-stems on the benches, or,
if the plants are potted, the pots may be set in a bedding of
stems, or the stems may be kept upon the pipes heating the
house, and this will give a sufficient impregnation to the air to
discourage many insects, while there is no danger to plants.

442 AN ECONOMIC ENTOMOLOGY.

This is especially effective in houses that are kept very warm and
moist.

Standing on much the same plane is pyrethrum, or " Persian
insect powder," or "buhach," which is a Californian product.
This is an exceedingly powerful contact poison, usually sold in
the form of a finely ground, yellowish powder, with a not un-
pleasant and somewhat pungent smell. Applied pure on most
insects of moderate size, and especially on larvae, it quickly
causes convulsions, and in most cases rapid death. It may be
mixed with two or three times its own bulk of cheap flour, and if
the mixture is kept in tight jars for twenty-four hours, all parts
of it will be equally effective. It is especially adapted for use
against plant-lice on a small scale, but is somewhat too expensive
for use in the field, or on a large scale. In small conservatories
nothing is better for general use, except against scale insects.
Where the dry powder is undesirable for any reason, use a de-
coction of an ounce in a gallon of water, first extracting with a
quart of boiling water and then adding cold water. Most naked
larvse are rapidly affected by this material ; and while it is espe-
cially a contact poison, yet it is also fatal when eaten, except
in the case of large or adult insects.

Among the contact poisons none ranks higher than kerosene,
either pure or made into an emulsion with soap. Pure kerosene
is fatal to almost all insects ; it is extremely penetrating, and
works its way through the spiracles into the body cavity and
through the trachea into all parts of it. This results in the prompt
choking of the insect. Pure kerosene is more or less injurious to
vegetation, although plants vary greatly in their resistance, and
it is therefore advisable to mix it with water, which can be ac-
complished by first emulsifying with either soap or milk. Prac-
tically, milk is rarely used at the present time, as the soap
formula is less expensive and, in general, more effective. The
following is the method of preparing the emulsion :

Hard soap, shaved fine one-half pound.

Water i gallon.

Kerosene 2 gallons.

Dissolve the soap in boiling water, warm the kerosene and add
the boiling hot suds to it ; then churn with a force-pump for a

/NSECriCIDES, PREVENTIVES, AND MACHINERY. 443

few minutes, and we get first a milky appearance, which yields
rapidly to a cream, and this to a soft butter-like mass. When
cold, this will adhere to glass without oiliness, and the emulsion
thus made, containing sixty-six per cent, of kerosene, may be
readily mixed with water to any extent. It is also quite stable,
and will remain unchanged for a considerable time. It is worthy
of note that the emulsion is much more easily made with soft
water, and if the water is very hard a permanent emulsion is
difficult to procure. It is always advisable, therefore, to use
rain-water, or to soften the hard water by adding soda or borax.
Diluted from nine to twelve times, this emulsion is very effective
against plant-lice, against many scale insects, and against a great
number of others already referred to in previous chapters. Ex-
cept in its pure condition, or in an almost undiluted emulsion,
scale insects are not killed with certainty by kerosene, nor are
insect eggs often affected ; yet the material has an extremely wide
range, and is among the most useful of our contact insecticides.

Another kerosene mixture is known as the " Cook emulsion,"
made as follows :

Soft. soap I quart.

Water 2 quarts.

Kerosene i pint.

Dissolve the soap in boiling water and add, boiling hot, to the
kerosene ; then churn as for the previous formula, and dilute
with an equal bulk of water before using. This is effective in
many cases as a mere soap-wash, and amounts to hardly more
than the addition of a little kerosene to strong soapsuds. The
formula is not recommended, except where the water is very
hard and no rain-water is available.

A combination of kerosene and pyrethrum has been made as
follows : Percolate through one pound of pyrethrum one gallon
of kerosene, or in that proportion, and use the extract in place
of the pure kerosene :

Hard soap i pound.

Kerosene extract of pyrethrum i gallon.

Water i gallon.

Emulsify as before.

444 ^^ ECONOMIC ENTOMOLOGY.

A modification, somewhat more easily prepared, is —

Kerosene i gallon.

Hard soap i pound.

Pyrethrum powder i pound.

Water i gallon.

Dissolve the soap in boiling water ; then add the pyrethrum, and
stir, while continuing to boil, five minutes ; then add the kerosene
and emulsify as before.

This mixture has been found effective with dilutions of from
four hundred to five hundred parts of water, but I have never
been able to secure equally satisfactory results. Indeed, in my
experience the pyrethrum adds little to the effectiveness of the
emulsion. • Yet I would not discourage experiments with the
mixture, which may work better in other hands.

Kerosene has also been used against scale insects on fruit-
trees in winter by spraying the pure material and in about ten
minutes setting fire to it. The kerosene burns off completely,
taking with it scales, moss, and fungous growths generally. This
use of it can be made on calm days only, as even a slow current
of air is apt to blow the flame from one side, making the applica-
tion ineffective.

Gasoline, a much lighter oil, is useful as a contact insecticide
in a limited number of cases. It can be applied to textiles in-
fested with ' ' moths, " or to carpets infested with ' ' carpet-beetles. ' '
It is very penetrating, kills everything it touches, and evaporates
rapidly without influencing unfavorably any but the poorest fab-
rics. The material is very inflammable, however, and this should
be kept constantly in mind when using it.

Soaps of various descriptions are useful contact insecticides,
and act through the stigmata, or breathing pores, by clogging
them and choking the insect to death. It is essential, to obtain
a good effect from a soap mixture, that the application be ex-
tremely thorough, so that each insect receives a complete coat-
ing. There is a great variety of insecticide soaps on the mar-
ket, but they all act in much the same way. In any good soap
the suds are capable of being thinned out to an almost impercep-
tible film, as we find in making soap-bubbles, and this, forming
over the spiracles, resists the entrance of air. We cover the in-

INSECTICIDES, PREVENriVES, AND MACHINERY. 445

sects with a fine coating of soap, which, in drying, closes up the
breathing pores, resulting in their death. It is thus that all
soaps act when used against j)lant-licc, larvai, or adult insects,
and it is readily seen that extreme thoroughness of application is
desirable.

After trying a large proportion of the soaps on the market, I
have found nothing more effective for general use than good
whale-oil soap : the term "whale oil" including any kind of fish
oil that can be obtained cheap. The soap may be made by the
farmer himself, according to the formulas given on every package
of lye ; but, practically, the material is sold so cheaply that, un-
less labor counts for nothing, it is as economical to buy as it is to
make it. Whale-oil soap contains a considerable amount of
caustic, and where a very thick suds is applied, we have not
only the effect of the oil, but the prolonged effect of the caustic
contained in it. It is, therefore, especially useful for destroying
scale insects, against which caustics alone exercise a satisfactory
effect. In whale-oil soap the caustic softens or lifts the scales,
while the oil in the soap chokes the insect to death. To kill
scales on trees it should be applied during the winter, when the
vegetation is dormant, at the rate of two pounds in one gallon
of water. To destroy plant-lice and most other insects feeding
upon leaves, an extreme application is one pound in four gallons
of water, which is as much as most plants will safely stand, and
which is also effective against most of the insects upon which it
can be used. Most plant-lice yield readily to one pound in six
gallons of water. In applying this material, thoroughness is es-
sential, and it is the disregard of this necessary feature that often
leads to failure.

It sometimes happens that a really good fish-oil soap is not
obtainable at a moderate price, and where it is desirable that a
satisfactory effect be obtained against resistant scales like the
San Jose, the following formula will make an effective material :

Concentrated lye .... 3>^ pounds.

Water 8 gallons.

Fish oil I gallon.

Dissolve the lye in boiling water, and to the boiling solution
add the oil ; continue to boil for two and one-half hours, and then

446 AN ECONOMIC ENTOMOLOGY.

allow it to cool. This makes an exceedingly caustic soap, which
is entirely reliable within its range of usefulness.

Carbolic acid is also valuable as an insecticide, and can be used
in the form of an emulsion prepared as follows : one pound of
hard soap, shaved fine, dissolved in one gallon of boiling water,
into which one pint of crude carbolic acid is then poured, and
the whole mass made into an emulsion with a force-pump, used
as in the case of the kerosene. This emulsion remains more or
less stable for a long time, and can be diluted with thirty parts
of water for effective use against certain classes of insects. It has
been recommended for cabbage-maggots, and at the strength
given will not injure the plants, while it seems to be fatal to the
young larvae. It is probably effective on soft-bodied insects in
general, but it undoubtedly derives a considerable proportion of
its effect from the presence of the large quantity of soap in the
emulsion.

Where lime is to be used as a repellent, the addition of one
pint of crude carbolic acid to one hundred pounds of the dry
hydrate will increase its efficiency, and few insects will touch
plants so protected. Among these few insects, however, we
find the rose-chafer.

The addition of carbolic acid to the whale-oil soap mixture is also
advantageous in certain cases. One ounce of crude carbolic acid
in each gallon of whale-oil soap mixture increases its effectiveness
as against plant-lice very considerably. One pound of whale-oil
soap in eight gallons of water, with four ounces of carbolic acid
added, will double the effectiveness of the mixture ; but as the
same result can be obtained with the soap alone in four gallons
of water, it becomes a mere question of cost and simplicity.

The whale-oil soap is often used in the form of a wash to pre-
vent the entrance of borers into fruit-trees, and in such cases the
addition of an ounce of the acid in a gallon of soapsuds seems to
add to its efficiency. It is claimed that trees treated with such
a mixture are much less attacked than those treated with the
soap alone. A little lime is sometimes added to a liquid of this
kind to make it more permanent.

Lime alone is useful as an insecticide in some instances. It
has been found effective by some and absolutely useless by
others, the difference in result being often due to a difference

INSECTICIDES, PKEVEXTIVES, AND MACIIIXEKY. 447

in the method of appHcation. As a rule, lime may be said to be
effective in proportion as it is caustic, and it is then useful against
soft-bodied insects. The best way to prepare it is to add just
water enough to stone or shell lime to dry-slake thoroughly, then
sift and apply the powder as soon as possible. This is more
caustic than air-slaked lime, and will burn a hole through the
soft body of most larvae. I have seen it applied on the slugs of
the potato-beetle in the morning while they were a little moist,
resulting before noon in their complete destruction. So it may
be applied to cabbages, and will in the same way destroy the
larvae of the cabbage-butterfly. Lime is one of the best mate-
rials for use on the larvae of the asparagus-beetle, and is also
effective against the slimy or moist saw-fly larvae, including the
"currant-worm." To obtain the best effects the lime should
be dry and caustic, while the insects upon which it is applied
should be damp or slimy. Wherever a particle of lime sticks
it will burn a hole into the insect. Few insects care to feed
upon limed vegetation, and many will not even rest upon a sur-
face covered by it ; therefore, lime may be sometimes used as
a repellent. Even the rose-chafer, when only moderately abun-
dant, will generally avoid lime-dusted foliage. Whitewashing
the trunks of trees will prevent the fixing of scale insects upon
them, and will discourage borers from laying eggs on or boring
into them. A free use of lime in every direction on the farm
is advised. Against the striped melon-beetles use one pint of
turpentine in one bushel of lime, applying freely to all parts of
the plant, and particularly around the base. This will keep them
off in most cases.

In some of the Pacific States resin washes are much used
against scale insects, apparently with excellent success. They
have not been as satisfactory when used in the East ; perhaps
due to the fact that the insects make thicker scales, or are more
completely dormant in the winter. The wash which has given
best satisfaction for summer use is made according to the follow-
ing formula :

Resin 20 pounds.

Caustic soda (seventy per cent, strength) ... 5 pounds.

Fish oil 3 pints.

Water sufficient to make 100 gallons.

448 AN ECONOMIC ENTOMOLOGY.

This mixture does not injure the trees or the foliage, and is
effective against young scales. It kills all that are moving about
in the larval condition, and also destroys recently fixed indi-
viduals; but it is ineffective against mature scales and the in-
sects under them. It acts by forming a thin varnish over the
scales, thus sealing up and choking them. In the mealy-bugs
and cottony scales it mats up and seals the eggs so completely
that the larvae find themselves unable to emerge. A stronger
wash, used in winter, is made according to the following formula :

Resin 30 pounds.

Caustic soda (seventy per cent, strength) . 9 pounds.

Fish oil 4^-2 pints.

Water sufficient to make 100 gallons.

To make this mixture, boil all the ingredients together with
twenty gallons of water until thoroughly dissolved, adding hot
water from time to time, but not, after the boiling begins, enough
to stop it. Three hours will be required for a complete mixture
of the materials, hot water to make fifty gallons being gradually
added and the mixture thoroughly stirred ; after this the balance
of one hundred gallons can be added in cold water. This is
really a soap varnish, deriving its effect from the caustic and
fish oil, while the resin forms an impenetrable covering. The
stronger mixture, or "winter wash," cannot be used in summer
without seriously injuring the foliage.

Another wash frequently used on the Pacific coast, and found
very effective against the San Jos6 scale and other insects, is a
lime, salt, and sulphur mixture, made as follows :

Unslaked lime 50 pounds.

Sulphur 25 pounds.

Stock salt 18 pounds.

Water sufficient to make 100 gallons.

This wash will do great damage to the trees if applied during
the growing season, and should be used only in winter. All the
sulphur and half the lime are placed in a kettle and twenty-five
gallons of water added, after which the contents of the kettle
are boiled briskly for an hour and a half, or until all the sulphur
is thoroughly dissolved. The solution, which at first is yellow

INSECTICIDES, PREVENTIVES, AND MACHINERY. 449

from the sulphur, will turn very dark brown, assuming more or
less of a reddish tint, and will finally change from a thick batter
to a thoroughly liquid condition, the product being ordinary
sulphide of lime. All the salt is added to the remaining lime
and the latter slaked, after which the slaked lime and salt are
added to the sulphide of lime already obtained, boiled an hour
longer, the whole being then diluted with water to make one
hundred gallons. This should be strained before application, as
it does not form a perfectly liquid solution, on account of the
considerable quantity of undissolved lime, which will soon settle
to the bottom unless the solution is constantly stirred while being
sprayed. A special nozzle with a rubber orifice is used for spray-
ing this mixture in California.

A modification, favored in Oregon, is, —

Unslaked lime 100 pounds.

Sulphur 100 pounds.

Blue vitriol 8 pounds.

Place all the sulphur and eighty pounds of lime in a kettle
with one hundred gallons of water and boil slowly until the sul-
phur is thoroughly dissolved. Dissolve the blue vitriol in hot
water, add to the remainder of the slaked lime, and mix the
whole together. This wall keep any length of time. When
ready to spray, use one gallon of the mixture in two and one-
half gallons of hot water and apply lukewarm. It may be used
as a summer wash by diluting one gallon with eight or ten gallons
of water.

These, though used successfully on the Pacific coast, have not
proved as satisfactory in the East. They have been thoroughly
tested by the agents of the Division of Entomology of the United
States Department of Agriculture, who do not recommend them
on the Atlantic coast. On the other hand, it should be said that
the kerosene emulsion seems to be much less effective on the
Pacific coast than it is in the East, and it is not unlikely that
distinct sets of remedies must be used under different climatic
conditions, these to be ascertained by direct experiments in the
various localities. Progressive farmers will make it a point to
get the bulletins of the Experiment Stations in their own States,
to learn from them those facts which apply particularly in their

29

45 o AN ECONOMIC ENTOMOLOGY.

own localities. The resin washes will not act well where frequent
rains and much dew dissolve the varnish formed by them over
the scales.

Caustic potash and caustic soda, dissolved in water, are very-
useful winter washes for fruit-trees. They can be used at the rate
of one pound in one or two gallons of water, and will destroy all
fungus growth and most of the common scale insects, leaving
the bark pure, fresh, and glossy for the following season. Inci-
dentally, all insects hiding under loose bark, or bark scales, are
also destroyed, as are many insect eggs. The application should
be confined to the trunk and larger branches, as there is danger
to green bark in so strong a wash, and no foliage or active plant-
tissue should ever be so treated.

Water alone, either very hot or very cold, is sometimes a use-
ful insecticide. Boiling water is quickly fatal to most insects
and to vegetation as well. At 125° it is effective against the rose-
chafer, killing it instantly, and at 140° it is still safe on grape
foliage. At 160° it kills all vegetation on which I tried it. It
has been applied with some satisfaction against cabbage-worms
without injuring the plants, and perhaps we may say that water
at a temperature of 125° is fatal to most insects and harmless to
most plants. But while this seems a very convenient and cheap
material, there are really grave practical difficulties in the way of its
general use. Even boiling water applied in a spray becomes too
cold twelve inches from the nozzle to be of any effect ; and so
rapidly do the small particles lose heat, that at a distance of three
feet it is reduced to atmospheric temperature. Its usefulness is
limited, therefore, to cases where it can be applied at short range
by a sprinkler, — c.g, on cabbage-plants ; and here the arsenites
are cheaper and more certainly effective.

Very cold or ice-water is effective against plant-lice under
some circumstances, and I have known of trees and bushes com-
pletely cleared by one application. But our knowledge of the
effects of cold on insects and plants is yet too small to make
practical recommendations possible.

Under some circumstances vapors can be made useful. Bi-
sulphide of carbon volatilizes readily at ordinary temperatures ;
the vapor is deadly to insects of all kinds, and is especially useful
against species infesting stored products, like grain and other

INSECTICIDES, PREVENTIVES, AND MACHINERY. 451

seeds. Where used in bins or closed receptacles, to kill insects
infesting their contents, one drachm should be counted for each
cubic foot of space, and a drachm may be roughly measured as a
teaspoonful. It may be placed in an open vessel on top of the
grain or other material, as the vapor, being heavier than the air,
will descend to the bottom. It is also useful in many cases
against plant-lice, and the range of the material has been already
given in the various cases for which it is recommended. It is
exceedingly inflammable and explosive, and in no building where
the material is used should a light be allowed or a fire of any
kind. Lighted pipes or cigars must be avoided, and even a
spark may cause an explosion. With ordinary precautions, how-
ever, the material is a useful one, since entire buildings can be
treated at once.

Hydrocyanic acid gas is another vapor exceedingly destructive
to all life, but much more fatal to animals than to plants. It may
be used for fumigating nursery stock or for destroying scale and
other insects on trees. The vapor is produced as follows : in a
glazed earthenware vessel place in the proportion of three fluid
ounces of water and one ounce of ordinary sulphuric acid ; then
add one ounce of fused potassium cyanide of ninety-nine per cent,
strength. This will generate a very light and extremely poison-
ous gas which is fatal to animal life of all kinds. The quantity
above given suffices for one hundred and fifty cubic feet, and for
a larger or smaller space a proportionate amount should be used.
Trees to be treated with this gas must be covered by a tight tent
of some kind, and for this purpose an eight-ounce duck, soaked
with boiled linseed oil, may be used. Where shrubs or small
trees are to be fumigated, a covered frame may be used and
placed over the plants by hand ; but where large trees require
attention, it will be necessary to have machinery mounted on
wagons. In the chapter on insecticide machinery, one of these
tents will be found figured. This hydrocyanic acid gas seems to
be less fatal to plants and more effective against insects at night
and in cool weather, and treatment at such periods is recom-
mended ; or the tent may be painted black. It should never be
used in hot weather during the middle of the day. This is
another case where an insecticide seems to be more effective on
the Pacific coast than in the East ; but it has not been sufficiently

452 AN ECONOMIC EiVTOMOLOGY.

tested in the Atlantic States to make it possible to either encour-
age or discourage its use. It has the advantage of being very-
thorough where it is at all effective, but the outfit required for
large trees is expensive.

Sulphur is an insecticide of comparatively limited range, but it
seems in some cases to prevent injury and has almost a specific
effect upon many of the mites which become troublesome in hot-
houses. It is sometimes applied by dusting the flour of sulphur
directly upon the plants, but is more usually applied in a watery
mixture. Many nurserymen place a considerable quantity of
crushed or powdered sulphur in a barrel and fill it with water,
stirring at intervals, and allowing it to remain for days or even
weeks, using from it and adding water as necessary. By boiling
with lime, the sulphur can be entirely dissolved, and a more
effective mixture will be obtained. In orange groves sulphur is
largely used against the rust mite, and is effective by simply
spreading it over the surface of the ground. It seems to cause a
slow fumigation of the trees sufficient to destroy the mites. Cu-
riously enough, this remedy seems less satisfactory on the
Pacific coast than it has been found in the East.

Gas-tar is sometimes recommended for certain purposes as an
insecticide, and more frequently as a repellent ; but it is rarely
of any practical value. It never serves to repel from any sur-
face which it does not cover and mechanically protect, — -that is to
say, its odor will not prevent insects from attacking plants near
it. It has been suggested that by placing it around the base of
plants like squashes, the borers can be prevented from entering
the plant ; but the moths will simply lay their eggs a little way
from it, and the caterpillars, when hatched, bore into the stem at
any point not actually touched by the tar itself Another
method that has been recommended is to put a quantity of tar
into a barrel and fill up with water ; then stir occasionally until
the water becomes impregnated with whatever it can dissolve
out. This, it has been said, is useful against plant-lice ; but I
have never found any beneficial effects from it, and deem it of
altogether too uncertain a value to be recommended.

Naphthaline has been used as an insecticide, but is of compara-
tively little value in the field, where its cost will prevent its gen-
eral use. The vapor given off by it is offensive and even poi-

IXSECTICWES, PREVENTIVES, AND MACHINERY. 453

sonous to many kinds of insects, so it may be used to protect
against their attacks in stored products. It has been said that a
sprinkhng of naphthahnc crystals on the surface of grain recep-
tacles will keep out all sorts of pests, and no doubt there is
more or less basis for this claim. Naphthaline is used to keep
museum pests out of boxes and cases containing specimens.
Packed with clothing, woollens, or fabrics of any kind in a toler-
ably tight box or closet, it will protect them from the attacks of
' ' moths. ' '

Quassia, in the form of a decoction, has been recommended
for insects of various kinds, noticeably plant-lice ; but, in my own
experience, the results obtained have been so unsatisfactory that it
would hardly pay to recommend it, when the soaps are so much
more effective as well as less expensive.

It remains to say a few words on the subject of patented insect-
icides, or mixtures sold under fancy names. As a general rule,
such should be avoided. Many of them are more or less merito-
rious, but in most instances they are paid for altogether too
highly. In some cases the name has covered a mere mixture of
Paris green and land plaster, charged for at many times its true
value, and then advertised, besides, as being harmless. The
range of the insecticides already mentioned will serve almost
every purpose required by the farmer, and before using any pat-
ented preparation, he should make an effort to ascertain just
what material he is applying to his plants. It is also advisable to
warn against the plausible schemes for preventing injury to trees
and other plants by " inoculation," — that is to say, placing
some substance into the body of the tree, with the idea that it
will be carried into the circulation to repel insects that might be
tempted to feed upon the foliage. All such preparations hereto-
fore used have been frauds, and no benefit has ever resulted from
any of them. In the same category belong those mixtures into
which seed potatoes or other seeds are to be dipped or rolled to
prevent the attacks of potato-beetles or other leaf-feeding insects.

454 AN ECONOMIC ENTOMOLOGY.

CHAPTER V.

MACHINERY.

Having determined the character of an injurious insect and
the remedy to be applied, it remains to decide the method in
which the appHcation is to be made, — i.e., whether the poison is
to be used dry or in a watery mixture ; and this necessitates
some information concerning pumps, nozzles, bellows, and the
like. There is no better indication of the progress of economic
entomology than the large number of firms now engaged in
manufacturing and supplying machinery for the application of
insecticides. Every agricultural journal contains advertisements
of such firms, and almost all of them issue illustrated catalogues
describing their wares. It will be for the farmer, with the knowl-
edge of his own requirements and necessities, to decide just what
kind of an outfit he needs, and all that can be done here is to
give a few suggestions as to the principles underlying the appli-
cation of insecticides.

Whether we apply dry powders or watery mixtures, the prime
essential in all cases is thoroughness. Where poisons are to
kill by contact, it is easily realized that contact is essential, — that
is to say, that the insect must be actually touched by the poison
to be at all effective. I have shown that such poisons kill in most
instances by either entering the body through the spiracles or
clogging them ; hence, also, the entire insect must be covered
by the poison, if it is to be entirely effective. Where stomach
poisons are to be used, it is equally essential that all parts of the
plant be covered, so that, no matter how little the insect eats, it
will yet obtain a poisonous dose. The amount of actual poison
required to kill most insects is very small, but in order that they
may obtain even this small quantity, the entire food-plant must
be covered. The essential feature of a perfect machine for ap-
plying insecticides is, therefore, that it shall quickly, thor-
oughly, and economically distribute whatever poison is used.
In some cases the application of dry poisons is desirable, though
the method is often a wasteful one, besides involving a greater

INSECTICIDES, PREVENTIVES, AND MACHINERY. 455

or less amount of expense for the diluting substance. Yet, when
such an application is advantageous, we find that there are very
few machines on the market for making it. The most elaborate
and practical machine is the Leggett " Champion Powder-Gun,"
which, by means of a fan-blower, distributes dry insecticides in a
very fine dust. With this machine, pure Paris green or London
purple can be applied so thoroughly that all parts of a plant
may be covered ; and as extension tubes and bent tips are fur-
nished, small trees or high bushes can be conveniently reached.
This is, I think, the best of the machines on the market for dis-
tributing dry powders of all kinds. It is manufactured by Leg-
gett & Brother, New York City, at a price of about $7.50.

There is a variety of smaller bellows made by other manu-
facturers, but they are scarcely practical for use on a large scale.
Those sent out from the Hammond Slug-Shot Works are as
satisfactory and as low in price as any, and the ' ' Woodason
Bellows," sold by most seedsmen and dealers in insecticides, are
also effective on a small scale. In this short list the machinery
for the application of dry powders is practically exhausted. There
have been many other machines produced and patented, and in
the reports of the United States Entomological Commission there
are numerous cuts and figures of expensive dusting arrangements,
none of which are in use at the present day. On the other
hand, the tendency is all towards simplicity. A great many
farmers who apply dry powders use the most rudimentary kinds
of dusters, — perforated tin pans or the like. The cotton growers
of the South have originated for their purpose a simple and very
effective method of applying dry Paris green, and perhaps this
will prove practical in other cases as well. It consists of a flex-
ible, tough pole, to each end of which a coarse cloth sack, filled
with pure Paris green or London purple, is tied. The stick is
rested across the back of a mule, which is slowly driven between
the rows of cotton, and the rider, striking continually with a
short stick on the flexible pole bearing the bags, jars them suffi-
ciently to dust out a very fine powdering of the poison. Practi-
cally, this is the most satisfactory method of applying the arse-
nites on cotton-plants that has been discovered, and it is now in
almost universal use where poisons are applied against the cotton-
worm. The method is extremely simple, and modifications of it

456 AN ECONOMIC ENTOMOLOGY.

adapted to his special use will occur to any intelligent farmer.
Applied through a sack, the dusting is exceedingly fine, while it is
at the same time thorough, at least so far as the upper side of the
leaves is concerned.

It is in spraying machinery that the greatest advance has been
made, and for a good spraying outfit there are two essentials, — a
pump and a nozzle. The tank containing the spraying mixture
may be almost anything, — a barrel, a tub, a box wagon, an elab-
orate tank cart, or even a pail. What his receptacle shall be,
each farmer may decide for himself. The pump may also be of
any type or pattern, provided that at least the working parts are
of brass, because otherwise the corrosive poisons are apt to destroy
it. For orchard work, or where large trees are to be sprayed,
the pump should give a pressure of one hundred pounds or more,
without requiring too much exertion. It should be double-acting
to give a continuous stream, and should have an air-chamber of
good size. The piston, or plunger, should not have too great a
diameter, because the greater the diameter the greater the amount
of force required to obtain a desired pressure. It must be re-
membered that in ordinary spraying operations the object is not
to throw the greatest possible amount of water in the least pos-
sible time, but to obtain the greatest amount of pressure with the
least expenditure of force. Force is to be looked for rather than
quantity of discharge. There are many pumps upon the market
fulfilling all the conditions above enumerated, and at various
prices.

Having selected the pump and mounted it upon any sort of
tank, the next question is as to the nozzle to be used. What we
want is the finest possible spray and the greatest possible amount
of force, and these two requirements are more or less antagonistic.
A very fine spray cannot be sent a great distance, and a jet
capable of being sent into the top of a high tree is a wasteful
method of application. There are, therefore, several types of
nozzles adapted for somewhat different classes of work. By all
odds the best, and the one having the greatest range of useful-
ness, is the Vermorel modification of the "cyclone" or eddy-
chamber nozzle. This consists, essentially, of a circular chamber
into which the water enters from one side under pressure, receiv-
ing thus a rotary motion. The point of exit is a single hole in

Fig. 473.

Our coniiiioii liumhlc-bees.— n, Xylncnpa vir_s:inica ; h, Rombus ferviihn ; r, B. consiniilis ; d, B.
virginicus ; r, B. antrricanoyum (queen) ; /', B . fmiidiis : .?-, A", amrn'canoruiii (worker), to show
pollen mass on hind tibia; h, /'. vagans ; i, Apalltus rlatus. All somewhat nH>re than natural
size.

INSECTICIDES, PREVENTIVES, AND MACHINERY.

457

the centre of a flat cap over the chamber. The water emerging
from this opening under high pressure has a whiding motion
which produces a cone-shaped spray of exceeding fineness, de-
pending upon the amount of pressure and the size of the opening.
With a good pressure and an opening one-sixteenth of an inch in
diameter, a fine mist-like spray can be sent a distance of ten feet,
and this fulfils as nearly as possible the requirements of an ideal
spray. In order that it may reach the tops of ordinary orchard
trees, it is necessary that the nozzle should be elevated, and a va-

FiG. 474.

V\^V.i.i!',VA'.^/V

Vermorel nozzle ami a section to show the working parts.

riety of means are adopted to attain that end. In some cases,
where extensive orchards of large trees are treated, the spraying
is done from a tank cart, and sometimes from a little scaffolding
built on it. More frequently, on moderate-sized trees, the hose
is tied to a bamboo pole from ten to fifteen feet in length, and
with this all such trees are easily reached. Instead of a bamboo
pole with the hose attached, some farmers use a gas-pipe of
proper diameter, to the end of which the nozzle is screwed.
This is somewhat lighter, and the slender pipe is more easily
managed. But all these are details which the agriculturist can
arrange for himself. A surprising amount of spray can be ob-
tained from a nozzle of this kind with a very small actual expen-
diture of liquid ; but where a great deal of spraying is done, two
or three nozzles grouped at the end of a larger discharge pipe are
sometimes used. The nozzles are so fixed that the spray is sent
in all directions, and a very large area is covered by the poison

458

AN ECONOMIC ENTOMOLOGY.

in a very short time. A moderate-sized tree can be sprayed with
a group of Vermorel nozzles in from one to three minutes. A
good pump will easily supply two lines of hose, and most of
those now made for orchard spraying are supplied with two dis-
charge openings. A three-quarter hose is all that is necessary,
even when a compound nozzle is used. The Vermorel nozzle
is supplied with a ' ' degorger, ' ' or apparatus for cleaning out
the spray opening in case it becomes clogged ; but it is not
easily clogged, and is, in fact, one of the most satisfactory from
that stand-point. With a screen at the bottom of the suction
pipe the meshes of which are not larger in diameter than the dis-
charge opening in the nozzle, clogging should be practically im-
possible.

Fig. 475.

The Nixon nozzle. — i, complete ; 2, 3, the two parts, separated.

The Nixon nozzle is a satisfactory bit of apparatus, working
on an entirely different principle from the cyclone. Here we
have a barrel-shaped cylinder of varying length, at the base of
which the water enters through a small opening in a solid jet, di-
rected against a wire screen at the tip of the cylinder. With a
good force behind it, a fine spray is sent from such a nozzle from

INSECTICIDES, PREVENTIVES, AND MACHINERY. 459

ten to fifteen foct. This nozzle has proved very satisfactory in
orchard work, but has the disadvantage of clogging very much
more readily than the cyclone, and of not clearing easily when
it does clog. With a proper netting at the end of the suction
pipe, the tendency to clog can be reduced to a minimum, and
with a little practice in actual field work, the nozzle has proved
satisfactory .

The McGowen nozzle is of yet a different type, and throws a
fan-shaped spray the quantity of which can
be varied by adjusting a spring which regu-
lates the size of the opening. The nozzle
has the advantage of being self-clearing, —
that is to say, any obstruction which may
lodge at the opening creates a pressure
sufficient to overcome the strength of the
spring, and the vent broadens sufficiently
to allow the escape of anything that can
get into the barrel of the nozzle. As soon
as the obstruction is removed, the spring
restores the opening as originally set. The
peculiarities of this nozzle are that the spray
can be thrown a much greater distance than
with any of the types previously mentioned,
and that the amount of liquid to be dis-
charged can be regulated. It has certain
advantages, therefore, in an orchard where
large trees are to be treated, but it does
not throw as fine a spray over so great a
surface as the Vermorel.

For spraying very large trees many
growers have found a cheap graduating
nozzle effecti\e. This is a cylinder with
a large flared opening, through which a
conical pin may be forced, even to its com-
plete closure. When the pin is completely
retracted, which is done by turning the
barrel of the nozzle, a solid jet is thrown,
and any intermediate grade between this and a tolerably fine
spray may be readily obtained. For spraying shade-trees nothing

The McGoweii nozzle
and a section through its
tip to show working parts.

460

AN ECONOMIC ENTOMOLOGY.

Fig. 477.

is more satisfactory than this, because it gives the greatest range
in distance and in quantity of discharge. Even if the spray is

coarser than with the other nozzles,
the work is more rapid. Practically,
it will not be necessary to go beyond
the nozzles already described to ob-
tain satisfaction.

The Vermorel modification of the
cyclone nozzle is manufactured by
almost all makers of insecticide
machinery, and can be obtained
anywhere. The graduating nozzle
may be purchased in almost any
hardware store, or wherever lawn
sprinklers and garden hose supplies
are sold. The Nixon nozzle is
patented, and obtainable from the
Nixon Nozzle and Machine Com-
pany, Dayton, Ohio, or from their
agents. The McGowen nozzle is
also patented, and obtained only
from J.J. McGowen, Ithaca, New York. There are many other
nozzles on the market, all of which have certain advantages,
from which the farmer must himself select those most useful to
him. So there are special nozzles for certain purposes, as that
for spraying the lime, salt, and sulphur mixture used on the
Pacific coast. All these are advertised by dealers in spraying
machinery, so that the intending purchaser can secure full in-
formation.

For spraying certain field crops on a large scale — e.g., pota-
toes—there is a tendency to use geared machines, — that is to say,
tanks mounted upon a cart, and the pump geared to the axle, so
that in simply driving through the field it will be operated. Then,
by means of an extension rod fitted with nozzles, from four to
six rows of potatoes or other plants can be sprayed at one time.
Several manufacturers make machines of this character, and a
great many of them are in use, giving satisfaction, as a rule.
They have the advantage of covering a great area in a very short
time, and reducing the cost of spraying to a minimum, doing the

A graduating nozzle.

INSECTICIDES, PREVENTIVES, AND MACHINERY. 461

work evenly and with little chance of missing. Where a large
acreage of potatoes is grown, one of these machines is almost in-
dispensable, and with it the potato-beetle can be kept in check
very readily. Of course these machines may also be used for
applying fungicides on the same plants. Geared machines should
never be used in spraying orchards ; or, if they are, the gearing
should be thrown off and the pump operated by hand. It is
practically impossible to spray orchard trees thoroughly by
simply driving between the rows and directing the spray from the
wagon to the trees as they are passed. If this is done, slipshod
work is apt to result which will not be effective, so that both
labor and money will be wasted and the spraying might as well
be omitted.

Of a somewhat distinctive type is the Bean spray pump, which
forms a spray by air-pressure, and is, indeed, practically an
atomizer. It is somewhat complicated, and has not found favor
in the East, though considered a satisfactory machine on the
Pacific coast. It is an apparatus not likely to clog, and the spray
produced by it leaves little to be desired. I have not seen it in
actual service, hence cannot say how well founded is the charge
of difficulty of manipulation.

' ' Knapsack pumps' ' have come into very general use of recent
years, and quite a variety are now manufactured, — all built upon
one general plan. There is a copper tank, holding usually in
the neighborhood of five gallons, and a double-acting pump con-
cealed within the tank itself, and operated by a lever that passes
either under the left arm or over the left shoulder. These knap-
sack pumps may be used for a very great range of work. As a
rule, they have a short discharge hose and a brass rod or " lance"
terminating in a Vermorel nozzle. The lance varies in length,
but its extreme is about thirty-six inches, so that low plants may
be easily reached while the worker is standing upright. In the
apparatus furnished by Boekel & Co., of Philadelphia, the nozzle
is adjustable in such a way that the spray may be sent in any
direction. If the under side of low plants is to be reached, the
nozzle is simply set so as to spray upward, and in fact it can be
adjusted so as to do almost any kind of work required in the
field and vineyard. For the grower of small fruits, including
grapes, a knapsack pump is almost indispensable. Bush fruits

^62 AN ECONOMIC ENTOMOLOGY.

like currants, gooseberries, blackberries, and raspberries can be
most satisfactorily reached by a machine of this kind, because it
can be easily operated wherever the operator himself can go.

There are many good, simple pumps now on sale, some of them
single-acting, — little more than a syringe, in fact ; others double-
acting, and throwing a fairly good jet for considerable distances.
These are usually termed "bucket pumps," and are satisfactory
in some cases, but are rarely advisable where work is to be done
on anything like a large scale. A good bucket pump is very
desirable, however, where kerosene emulsion is to be made, and
it will easily pay for itself, by facilitating the preparation of this
material, if it is to be used in quantity. With a good bucket
pump three gallons of emulsion may be made in five minutes
after the soapsuds have been heated to the boiling-point.

This is hardly the place to recommend makers of insecticide
machinery or machines of special types. The farmer, before
purchasing, should look through the advertisements in his farm
papers, and write for catalogues to those advertising spraying
machines. From these catalogues he should be able to select
a proper outfit for his special purpose, keeping in mind the
recommendations that have been made in this chapter. There
is, however, one warning that must be given : the cheapest outfit
is not always the one that costs the least money ! Durability
should be looked to as well as effectiveness and simplicity of
structure, so that if there is anything out of order it can be
readily repaired by the farmer himself. Strength is desirable in
all the parts, and the structure of the valves and the character of
the packing should be looked to. Cheap pumps, as a rule, have
unreliable valves and ordinary cotton packing. The best pumps
have brass valves and metal packing, so that, except in cases of
accident or extreme carelessness, repacking is not required for
years, if at all. In fact, a pump should be selected just as care-
fully as any other piece of machinery, and when a proper outfit
is purchased, it should be studied until it is thoroughly under-
stood. It will then be possible to use it with satisfaction, and the
results are apt to be good.

There is now upon the market a machine to avoid making
an emulsion where kerosene is to be used, by providing for a
mechanical mixture of kerosene and water in the proper propor-

INSECTICIDES, PREVENTIVES, AND MACHINERY. 463

tions in the act of spraying-. At the present writing this machine
is not sufficiently perfected to warrant me in recommending it,
but no doubt practical machines will be constructed, in the near
future, carrying kerosene in one tank and water in another, with
a pump so arranged that the materials will combine in a mechani-
cal mixture that can be satisfactorily applied to plants.

Fig. 479.

An " emulsion" knapsack sprayer for combining kerosene and water.

For applying insecticides underground, which is sometimes
desirable in using bisulphide of carbon against the cabbage-root-
maggot and other subterranean species, there is only one satis-
factory piece of machinery, — the McGowen injector. This is best
explained by Fig. 481, illustrating its use on cabbages. The fol-
lowing directions may be observed, and will at the same time
indicate the method in which the machine may be used for other
purposes.

The method of inserting the injector is shown in Fig. 481.
The hole should always begin at a distance of three or four inches

Fig. 481.

Fig. 480.

Fig. 478.

f

Fig 480, the McGoNSMi mp . t'ji in section, showing its working parts. Fig. 481, illus-
trating method ol using McGowen injector. Fig. 478, a knapsack sprayer.
464

INSECTICIDES, PREVENTIVES, AND MACHINERY. 465

from the plant, and run horizontally downward to a point a little
below the roots. To accomplish this the injector must be inserted
at an angle, as shown in the figure. Force it down until the
point is a little below the roots, then let out the charge of liquid.
In operating the injector, first pull the piston up as far as it will go.
This loads the measuring chamber between the vahes. Then
push down the piston until it stops, and the instrument is ready
to be pushed into the ground. Push it into the ground as far as
desired. Hold it there while you pull up the piston. By this
operation you let the charge out of the lower chamber into the
ground, and at the same time the measuring ciiamber is again
filled. Hold the injector in the ground a few seconds after the
piston has been pulled up, in order that all the liquid in the
charge may have a chance to run out. Then pull the injector
out of the ground, and quickly, with the foot, fill the hole with
earth and step on it to pack it down. Press down the piston,
and you are ready to treat the next plant. Never push the
injector into the ground unless the piston is clear down, because,
if the lower end is not thus closed, it will immediately fill with
soil, which is not easily removed. Study the drawings in Fig.
480, in connection with these directions, and you will under-
stand the reason for each step. We would advise that the reser-
voir be fi«-st filled with water and the injector operated above the
ground until each step is thoroughly understood. There is
nothing complicated about the instrument or the way it is to be
operated. It can be easily taken apart and cleaned, if necessary ;
the only caution to be observed in replacing the parts is to have
the flanges of the leather in the upper valve turned upward.
The injector is made by John J. McGowen, Ithaca, New York.

Under this head we may refer to the "hopper-dozers" which
have been recommended against certain Hemiptera and Orthop-
tera. These are simply shallow pans of thin sheet-iron, of con-
venient length for the special use intended, mounted on runners
so high as to bring the bottom of the pan to the top of the vege-
tation to be treated. The runners can easily be made adjustable in
height by any clever mechanic. The front of the pan is turned
up enough to prevent its cutting or otherwise injuring vegetation,
and the sides are also turned up at least two inches and the cor-
ners made sufficiently close to hold water, if necessary. Along

466 AN ECONOMIC ENTOMOLOGY.

the hinder edge is stretched a canvas-covered, upright frame, at
least twelve inches high, which prevents grasshoppers from jump-
ing over the machine. The ' ' dozer' ' may be drawn by man or
by horse-power, and when in use the bottom is covered with crude
petroleum, or with water on which is floated a film of kerosene.
The canvas-covered frame is also moistened with kerosene. As
the apparatus is drawn through the fields the insects jump up
before, and usually, in trying to leap over, fall into it. Even if
they jump out again immediately, they are doomed, because

Fig. 482.

" Hopper-dozer" for man-power.

once wet with kerosene they die in a few minutes. These
machines are useful only on comparatively level ground, but they
often destroy great numbers of injurious insects when properly
handled.

Finally, we may say a few words concerning fumigating appa-
ratus. No two outfits are quite alike, and the work to be done
must in every case determine the character of the machinery.
The essentials are a gas-tight tent, and a means of placing it over
the plants to be fumigated. The method of producing the gas
is elsewhere described. For the tent, eight-ounce duck, saturated
with boiled linseed oil, is recommended, and it should be made
to close so tightly that little gas can escape through the lap. As
for the machinery to place it over the tree, that must be in all
cases determined by the circumstances ; but Fig. 483 will give an
idea of the way things are done in California. The outfit is an
expensive one, and will pay only when an entire neighborhood
can be supplied by it.

Fk;. 4S;v

The Wullnkill niiuiLialur.

INDEX.

Abdomen, how made up, 26.
Acanthia Icctularia, 155.
Achatodes zcce, 299.
Acrididre, defined, 85.

life history, 89.
Acridium species, 89.
Acronycta americana, 289.
Actias luna, 282.
Aculeata, defined, 390.
Adaha bipuncta, 174.
Adephaga, defined, 165.
AgalHa sanguinolenta, 147.
Agaristidre, 264.
Agricuhural ants, 398.
Agrilus ruficolhs, 186.

sinuatus, 187.
Air-sacs or bladders, 36.

-tubes, extensile, 37.
Alaus oculatus, 183.
Alder-blight, 133.
Aletia argillacea, 301.
Aleyrodes citri, 122.
AleyrodidtE, 121.
Allorhina, species, 203.
Alulet, 365.

Alypia octo-maculata, 263.
Ambulatoria, 81.
American blight, 133.
Amm. solution of copper carbonate, 439.
Amphicerus bicaudatus, 195.
Anabrus simplex, 97.
Anal glands and secretions, 30.
Anasa tristis, 160.
Anatis 15-punctata, 174.
Andrena species, 411.
Angoumois grain moth, 326.
Anisopteryx species, 307.
Anisota senatoria, 278.
Anomala lucicola, 202.

Anomis species, 300.
Antenn;\;, function of, 20.

general characters, 19.
Anthocoridas, 156.
Anthomyiids, 360.
Anthonomus 4-gibbus, 232.

signatus, 231.
Anthrax, species of, 345.
Anthrenus scrophularioe, 179.
Ant-lions, 76.
Ants, described, 390.

and plant-lice, 127, 394.
Apanteles species, 383.
Aphaniptera, 328.
Aphelinus mytilaspidis, 385.
Aphididse, 123.
Aphidius species, 384.
Aphis-lions, 74.

mali, 134.

parasites, 383.

persicae-niger, 134.
Aphodius, 198.
Apis mellifica, 414.
Apple, Anthonomus on, 232.

blight-louse, 133.

case-bearer, 324.

codling moth on, 322.

flat-head borer in, 186.

leaf-crumpler, 313.

long-horned twig-borers, 209.

-louse, 134.

-maggot, 366.

oyster-shell scale on, 115.

round-head borer in, 209.

tree-hoppers on, 138.

twig-borer, 195.

yellow-neck caterpillar, 275.
Aquatic forms, how they breathe, 36.
Aramigus fuUeri, 228.

467

468

INDEX.

Arbor-vitse, bag-worm on, 273.
Arctiidse, 266.
Argynnis species, 244.
Arista of flies, 330.
Armored scales, 114.
Army-worm, 294.
Arsenate of lead and its use, 436.
Arsenic as an insecticide, 437.
Arsenites and their use, 434, 438.
Ascalaphus species, 76.
Asilidoe, 344.
Asopia costalis, 312.
Asparagus beetle, 211.
Aspidiotus perniciosus, 118.
Atomaria species, 177.
Atropos species, 69.
Attacus species, 279,
Auditory sense of insects, 43.
Automeris io, 283.

Bag-worms, 273.
Balancers of flies, 327.
Balaninus species, 234.
Bandings of printers' ink, etc., 433.
Bark-beetles, 237.

-slippers, 207.
Beak of bug mouth, 16.
Bean lady-bird, 175.

-weevils, 223.
Bean spray pump, 461.
Bed-bug, 155.
Beech blight, 133.
Bees, 407.

long- and short-tongued,4io.
Bee-flies, 345.

-louse, 370.

-moth, 316.

mouth, 19.
Beet-leaf magots, 365.
Beetles, chapter on, 164.

classification of, 165,
Bell moths, 319.
Bellows, 455.

Belostoma americana, 150.
Bembecia marginata, 260.
BembecidfE, 403.
BibionidcC, 340.
Bichloride of mercury, 438.
Bill-bugs in corn, 236.

Bipectinated antennae, 21.
Bisulphide of carbon, 450.

against hen-lice, 71.
against Termites, 67.
Biting lice, described, 70.
Bittacus, 77.

Black beetles, their habits, 82.
Blackberry cane-borer, 186.

crown-borer, 260.

pithy gall, 378.

root-borers, 206.

saw-fly borer, 375.
Black flies, 340.
Blattidse, described, 81.
Blennocampa pygmsea, 374.
Blissus leucopterus, 158.
Blister beetles, 225.
Blood of insects, 33.
Blow-fly, 257.
Blues and coppers, 245.
Body-louse, life history, 105.
Boll-worm, 303.
Bombardier beetles, 168.
Bombyliidae, 345.
Bombylius species, 345.
Book-lice, 68.
Borax, against roaches, 82.
Bordeau.x mixture and its uses, 439.
Boreal lady-bird, 175.
Borers, remedies for, 188.
Boreas, j^.
Bostrychus, 193.
Bots on cattle, 352.
Bot-flies, 351.
Brachinus, 168.
Brachystola magna, 91.
Braconidae, 382.
Brain in insects, 39.
Bran and Paris green, 438.
Braula cEeca, 370.
Breast-bone of gall-gnats, 336.
Breathing of insects, 33.
Bristle-tails, 53.
Bristled antennee, 22.
Bruchidag, 223.
Brush-footed butterflies, 242.
Bucket-pumps, 462.
Buffalo gnat, 340.

grasshopper, 91.

INDEX.

469

Buffalo moth, 179.

tree-hoppers, 138.
Bugs, defined, 100.
Buhach, 442.
Bumble-bees, 411.

life history, 416.
Buprestidas, 185.
Buprestis, 185.
Butterflies, chapter on, 240.

classified, 241.

mouth of, 16.
By turns unicolor, 180.

Cabbage butterflies, 246.

harlequin bug on, 162.

-lice, 134.

-maggot, 361.

Plusia, 302.

thrips, 102.

-worms, parasites on, 385.
Cacoecia fervidana, 321.

rosaceana, 321.
Caddice-flies. 77.
Cadelles, 182.

Caecal tubes or pouches, 30.
Calandra, species of, 237.
Calliphora vomitoria, 357.
Camel crickets, 97.
Canker-worms, 307.
Capsidas, 156.
Carabidoe, 166.

Carbolic acid and its uses, 446.
Carbon disulphide and its uses, 450.
Carnivorous beetles, 165.
Carolina locust, 88.
Carpenter ants, 391.

bees, 412.
Carpet beetle, 179.
Carpocapsa pomonella, 322.
Carpophilus hemipterus, 181.
Carrion beetles, 171.
Cassida bivittata, 222.
Cassidae, 222.
Catch crops, use of, 426.
Caterpillar hunters, 168.
Catocala species, 306.
Caustics, how they kill, 39.
Caustic potash and soda washes, 450.
Cecidoniyia destructor, 336.

Cecidomyia leguminicola, 338.
Cecidomyida;, 336.
Cecropia moth, 280.
Cephalo-thorax, defined, 34.
Cephus pygmceus, 376.
CerambycidiK, 205.
Ceraphron triticum, 388.
Ceratocampidae, 278.
Ceratomia amyntor, 257.
Ceratopogon species, 334.
Ceratopsyllus serraticeps, 329.
Ceresa bubalus, 139.
Cerci, defined, 26.
Cercopidae, defined, 146.
Ceroplastes, 112.
Chretocnema confinis, 219.
Chalcidida;, 384.
Chalcophora, 185.
Chauliodes pectinicornis, 72.
Chauliognathus, 191.
Chermesinas, defined, 128.
Cherry-louse, 134.
Chestnut weevils, 234.
Chicken-fleas, 329.

-lice, 71.
Chickens versus insects, 426.
Chilo species, 317.
Chilocorus bivulnerus, 174.
Chinch-bug, life history, 158.
Chinese silkworm, 286.
Chionaspis furfurus, 119.
Chironomidce, 333.
Chitine, peculiarities of 14, 38.
Chortophaga viridifasciata, 88.
Chrysalis, defined, 50.
Chrysanthemum fly, 348.
Chrysididoe, 390.
Chrysobothris, 186.
Chrysomelidas, 205, 210.
Chrysopa, 74.

Chrysophanus, species of, 245.
Chylific ventricle, 30.
Cicada, defined, 139.

septendecim, 140.
Cicindelidse, 166.
Cigarette beetle, 193.
Ciliated antennae, 22.
Cimbex americana, 374.
Circulation in insects, 33.

47°

INDEX.

Citheronia regalis, 278.
Classification in general, 52.
Clavate antennas, 21.
Clavicornia, defined, 165.
Cleanliness, to check insects, 423.
Clear-wing moths, 259.
Cleridae, 192.
Clerus apivorus, 192.
Click-beetles, 182.
Climbing cut-worms, 292.
Clisiocampa americana, 284.
Clothes moths, 324.
Clothilla. 69.
Clothing of bees, 408.
Clover hay-worm, 312.

leaf-beetle, 229.

seed-midge, 338.

stem-borer, 176.
Coccidse, defined, 106.
Coccinella 9-notata, 174.
Coccinellidae, 172.
Cochineal insect, 106.
Cockchafer, 201.
Cockscomb gall on elm, 132.
Cocoon, described, 50.
Codling moth, 322.
Coleoptera, defined, 54, 55.

chapter on, 164.

classification of, 165.
Colias philodice, 250.
Colon, described, 30.
Colopha ulmicola, 132.
Colorado potato-beetle, 213.
Commercial fertilizers as insecticides,

427.
Complemental sexes of Termites, 66,
Complete metamorphosis, 50.
Compound eyes, 42.
Cone-nosed grasshoppers, 96,
Conocephalus, 96.
Conopidre, 351.
Conorhinus sanguisuga, 152.
Conotrachelus cratsegi, 234.

nenuphar, 232.
Contact poisons, how they act, 38.
Cook emulsion, 443.
Coppers and blues, 245.
Copris Carolina, 198.
Coptocycla aurichalcea, 223.

Coreidae, defined, 160.
Corimelasnidae, defined, 163.
Corn bill-bugs, 236.

-root Diabrotica, 215.

-root-louse, 134.

-root web-worm, 317.

-worm, 303.
Cornicles, defined, 126.
Corisa, habits of, 150.
Coriscus, 153.
Corrodentia, 68.
Corrosive sublimate, 438.
Corticaria, 177.
Corydalus cornutus, 72.
Corynetes rufipes, 193.
Cossidae, 286.
Cotalpa lanigera, 202.
Cotton boll-worm, 303.

r^-bug on, 157.

-.stj|liner, 157.

-worm?, 300.
Cottony cushion scale, 108.

maple scale, no.
Cow-lice, how destroyed, 71.
Coxa, defined, 26.
Coxal cavity, defined, 26.
Crab-louse, 105.
Crambids, 316.
Crambus species, 317.
Cranberry fire-worm, 320.

fruit-worm, 313.

span-worm, 309.

Teras, reflowing for, 428.
Crane-flies, 330.
Cremastogaster lineolata, 392.
Crepidodera, 219.
Crickets, 97.
Crioceris asparagi, 211.

i2-punctatus, 211.
Crop, described, 30.

of lepidoptera, 31.
Crop remnants should be removed, 424,
Croton bugs, 82.
Cruciferous weeds, lice on, 134.
Cryptophagus, 177.
Cuckoo-bees, 390.
Cucumber caterpillar borer, 311.

flea-beetle, 219.

striped beetle, 214.

INDEX.

471

Cucujidae, 176.

Culicidoe, 332.

Cupram, use and formula, 439.

Curculio, defined, 228.

Currant borer, 263.

4-lined plant bug on, 156.

long-horned borer in, 208.

worm, 372.
Cursoria, defined, 81.
Cuterebera emasculator, 352.
Cut-worms, life history, 290.

remedies for, 293.
Cyclone nozzle, 456.
Cydnidce, defined, 162.
Cyllene pictus, 208.

robinia;, 208.
Cymatophora pampinaria, 309.
Cynipidoe, defined, 376.
Cyrtophyllum concavum, 94.

Dagger moths, 289.

Danais archippus, 242.

Darkling beetles, 224.

Dascyllidae, 182.

Datana ininistra, 276.

Day-flies, 59.

Death-watch, 69.

Delta moths, 306.

Deltoids, 306.

Dendrolene and raupenleim, 431.

Dermaptera, 79.

Dermestes lardarius. 178.

vulpinus, 178.
Dermestidae, 178.
Devil's darning-needles, 60.
Diabrotica longicornis, 215.

i2-punctata, 215.

vittata, 214.
Diapheromera femorata, 86.
Diaspinae, defined, 114.
Diaspis rosce, 119.
Diastrophus nebulosus, 378.
Diatroea saccharalis, 318.
Dicerca, 185.

Dictyophorus reticulatus, 91.
Digestive system, described, 28-30.
Digger wasps, 399, 403.
Diplosis pyrivora, 339.

tritici, 338,

Diptera, chapter on, 327.

defined, 54, 55.
Diseases of insects, 418.
Dissosteira Carolina, 85.

longipennis, 85.
Dobson, 72.
Dog-flea, 328.
Dorsal surface, 25.
Dorsum, is upper surface, 25.
Doryphora lo-lineata, 213.
Dragon-flies, 60.
Drasteria crassiuscula, 305.

erechtea, 305.
Drone-fly, 348.
Drosophila species, 367.
Dryocampa rubicunda, 279.
Dry powders, how applied, 4S4,

how they kill, 39.
Dynastes, 203.
Dysdercus suturellus, 157.
Dytiscidce, 169.

Ears of insects, 43.
Earwigs, life history, etc., 79.
Economic entomology, development of,

9-
Ectobia germanica, 82.
Edema albifrons, 277.
Eggs, number laid by insects, 45.

of mantidas, 84.

of roaches, 81.

stage described, 48.
Eight-spotted forester, 263.
Elaphidion species, 207.
Elateridas, 182.
Electric-light bugs, 151.
Elm, cockscomb gall on, 132.

leaf-beetle, 217.

4-horned sphinx on, 257,
Elytra, 164.
Emasculating bot, 352.
Empretia stimulea, 271.
Enemies of insects, 45.
Ephemeroptera, described, 59.
Ephestia kiihniella, 315.
Epidapus scabei, 335.
Epicauta cinerea, 227.

pennsylvanica, 227.

vittata, 225.

472

INDEX.

Epidemics among insects, 45.
Epilachne borealis, 175.

corrupta, 175.
Epipharynx, function of, 15, 43.
Epitrix, 219.
Eriocampa cerasi, 372.
Eristalis tenax,348, 350.
Erotylidae, 175.
Erythroneura vitis, 148.
Euchromia ipomaese, 264.
Eucleidae, 271.
Eumenes, nests of, 404.
Euphoria inda, 204.
Euplexoptera, 79.
Eupogonius, 209.
Eurycreon ran talis, 311.
Eyes, compound, 22.

of insects, 41.

Fall army-worm, 297.

plowing, effect of, 425.

web-worm, 266.
Family, defined, 52.
Farm practice to prevent iasect attack,

423-
Feather-wing moths, 318.
Feeding habits, how determined, 14.
Feelers are antennas, 19.
Femur, defined, 26.
Fenesica tarquinius, 246.
Fertilizers as insecticides, 427.
Fidia viticida, 211.
Filicornia, defined, 165.
Filiform antennae, 21.
Fire-flies, described, 190
Fish-moth, 53, 56.

-oil soap, use and formula, 445.
Flat-head borers, 185.
Flax-seed stage of Hessian fly, 336.
Flea-beetles, 219.
Fleas, described, 328.
Flesh-flies, 356.
Flies, chapter on, 327.
Flower-beetles, 192.

-flies, 347.
Fly, experiments with, 41.
Foraging ants, 399.
Forficulidoe, defined, 79.
Formicidce, 391.

Fossores, 399.
Four-lined plant-bug, 156.
Fowls, affected by lice, 71.
Frog-hoppers, 146.
Fruit bark-beetle, 238.
Fulgoridae, defined, 146.
Fuller's rose-beetle, 228.
Fumigating apparatus, 465.
Funicle of antenna, 22.
Fungus diseases of insects, 418, 422.
gnats. 334.

Galeruca xanthomelaena, 217.
Gall-flies, 376.

-gnats, 336.

-lice, described, 132.
Galls, ink from, 378.
Galleria melonella, 316.
Ganglia, described, 39.
Garden web-worm, 311.
Gas-tar as an insecticide, 452.
Gasoline as an insecticide, 444.
Gasirophilus equi, 351.
Geared machines, 460.
Gelechia cereallella, 326.
Geniculate antennce, 22.
Genus, defined, 52.
Geometridce, 307.
Geotrypes, 198.
Gills, of aquatic insects, 37.
Gizzard, described, 30.
Glow-worms, 190.
Gnats, 334, 340.
Goat-moths, 286.
Goldsmith beetle, 202.
Gouty gall on blackberry, 186.
Graduating nozzle, 459.
Grain-weevils, 237.
Grape, American Procris on, 264.

chafers on, 202.

8-spotted forester on, 263.

flea-beetle, 219.

leaf-hopper, 148.

phylloxera, 128.

plume-moth, 318.

Pyrophila on, 299.

-root-worm, 206, 212.

-slug, 373.
Grapta comma, 244.

nXDEX.

473

Grass, leaf-hoppers in, 147.

thrips on, 102.
Grasshoppers, life-history, etc., 89.

long-horned, 93.

short-horned, 85.
Green-striped locust, 88.
Ground-beetles, described, 166.
Grouse locusts, life-history, 92.
Gryllidae, defined, 97.
Gryllotalpa, 98.
Gryllus, species, 99.
Gypsy moth, 270.
Gyrinidns, 170.

Hasmatobia scrrata, 358.
Hair-streaks, 245.
Halisidota, species, 268.
Halteres, of flies, 327.
Haltica chalybea, 219.
Ham-beetle, 193.
Hammer-head borers, 185.
Harlequin cabbage-bug, 162.
Harrisina americana, 264.
Harvest-flies, 139.
Haustellate mouth-structures, 16.
Hawk-moths, 254.
Head and its appendages, 14.

-louse, 103.
Hearing of insects, 43.
Heart, described, 32.
Heliothini, 303.
Heliothis armiger, 303.
Hellebore and its use, 440.
Hellgrammites, 72.
Hemerobiidce, described, 72.
Hemerobius, 74.
Hemiptera, chapter on, 100.

defined, 53, 55.
Hen-lice, 71.
Hermaphrodites, 46.
Hesperidae, 254.
Hessian fly, 336.

effect of late planting, 428.
Heterocera, 241, 254.
Heteromera, defined, 165, 224.
Heteroptera, defined, .S3, 100.

treated, 150.
Hickory horned devil, 278.

phylloxera on, 130.

Hippiscus discoideus, 88.
Hippoboscidae, 369.
Hippodamia, 174.
Hispidai, 221.
Histeridae, 180.
Hive-bee, 414.
Hog-caterpillars, 257.

-louse, 104.
Homoptera, defined, 53, 100, 106.
Honey-ants, 396.

-bee, 414.

-dew, 126.

-tubes of plant-lice, 126.
Hop, Grapta on, 244.

-louse, life history, 125.

snout-moth, 306.
Hopper-dozers, 92, 464.
Horn-fly, 358.

-tails, 371, 374.
Hornets, 406.
Horse-bot, 351.

-flies, 342.
House-fly, 356.

Household pests, 56, 82, 155, 356, 396.
Humming-bird hawk-moths, 257.
Hybernia tiliaria, 308.
Hydrate of lime, dry, 447.
Hydrobatidas, defined, 151.
Hydrocyanic acid gas, 451.
Hydrophilidas, 170.
Hymenoptera, chapter on, 370.

defined, 54, 55.
Hypena humuli, 306.
Hyperchiria io, 283.
Hyper-parasites, 388.
Hyphantria cunea, 266.
Hypoderma lineata, 352.
Hypopharynx, structure and function,
16, 43-

Icerya, Vedalia against, 421.

purchasi, 108.
Ichneumon flies, 381.
Ichneumonidce, 381.
Ileum, described, 30.
Indian Cetonia, 204.
Incomplete metamorphosis, 50.
Injectors, 433.
Inoculation of trees, 453.

474

INDEX.

Insect powder, 442.

Insecticides, chapter on, 418, 434.

Insects, defined, 11, 12, 54.

Insidious flower-bugs, 156.

Introduced insects, 421.

Introductory, 9.

lo moth, 284.

Ipomaga, larvae on, 264.

Ips fasciatus, 181.

Isabella moth, 266.

Isomera, defined, 165.

Isoptera, 64.

Isosoma species, 386.

Jassidag, defined, 147.
Jigger-fleas. 329.
Joint-worms, 386.
Jug-handle grubs, 254.
Jumping plant-lice, 137.
June-bugs, 200.

Kainit, against root-lice, 131.
Katydids, described, 94.
Kermes, described, no.
Kerosene as an insecticide, 442.

how it kills, 38.
Knapsack pumps, 461.

Labium, structure and function, 16.
Labrum, structure and function, 15.
Lace-wing flies, their habits, etc., 74.
Lachnosterna, 201.
Lady-birds, described, 172.
Loetilia coccidivora, 315.
Lamellate attennag, 21.
Lamellicornia, defined, 165, 196.
Lampyridae, igo.
Lancets of fly mouth, 18.
Languriamozardi, 176.
Lantern-flies, described, 146.
Laphria, species, 344.
Laphygma frugiperda, 297.
Larder-beetles, 178.
Larridse, 403.

Larvae distinguished from worms, 11.
Larval stage, 48.
Lasioderma serricorne, 193.
Lasius species, 394.
Lawns, ants on, 395.

Leaf-beetles, described, 210.

-chafers, 199.

-hoppers, described, 146.
life-history, 147.

-roller caterpillars, 319.
Leather-beetle, 178.
Lebia grandis, 168.
Lecanium, defined, 112.
Leggett Champion Powder-gun, 455,
Legs, where located, 25.

structure of, 25.
Lema trilineata, 211.
Leopard-moth, 287.
Lepidoptera, chapter on, 240.

defined, 54, 55.
Lettuce, root-lice on, 127.
Leucania albilinea, 296.

unipuncta, 294.
Lice, biting, their habits, etc., 70.

on domestic animals, 71, 105.

sucking, 104.
Life-history, defined, 50.

economic importance of, 50.
Ligyrus rugiceps, 203.
Limacodidae, 271.
Lime as an insecticide, 432, 446.

as a preventive, 432.

salt, and sulphur wash, 448.

-tree moth, 308.
Limnophilus rhombicus, 78.
Litargus, 177.
Lixus concavus, 230.
Locomotion, organs of, 25.
Locust borer, 287.

leaf-beetle, 222.
Locustidae, defined, 93.
Locusts or cicadas, 140.
Locusts, destructive species, 90.

remedial measures, 92.
London purple, analysis of, 435.
Long-horned beetles, 205.
Loopers, 307.

Losses caused by insects, 9.
Louse-flies, 369.
Lo.xostege similalis, 311.
Lubber grasshoppers, 91.
Lucanidae, 196.
Lucanus species, 197.
Lucillia macellaria, 357.

INDEX.

475

Luna-moth, 282.
Lyctena, species of, 245.
Lycaenidae, 242.
Lygasida;, defined, 158.
LymantriidtC defined, 268.

Machinery, chapter on, 418, 454.

Macrobasis nnicolor, 227.

Macrodactylus subspinosus, 199.

Malachiida;, igr.

Mallophagidce, 70.

Malpighian tubules, 30.

Mandibles, structure and function, 15.

Mandibulate mouth, 15.

Mantidae, described, 83.

Mantis religiosa, 84.

Mantispidae, 76.

Manure, favors insects, 428.

podurids breed in, 57.
Maple-borer, 208.

clear-wing borer, 262.

scale, life-history, no.
March-files, 340.
Margaronia nitidalis, 311.
Mask of dragon-fly larva, 62.
May-beetles, 200.

-flies, their habits, etc., 59.
Maxillae, structure and function, 15.
McGowen nozzle, 459.

injector, 463.
Meadow-grasshoppers, 96.
Meal-worms, 224.
Mealy-bugs, described, 106.

remedies for, 108.
Measuring-worms, 307.
Mecoptera, 77.

Mediterranean flour-moth, 315.
Megachile species, 412.
Megathymus yuccae, 254.
Megatoma, 179.
Megilla, 174.
Melanophila, 185.
Melanoplus atlanis, 90.

femur- rubrum, 90.

spretus, 90.
Melitara dentata, 313.

prodenialis, 313.
Melittia ceto, 259.
Meloidae, 225.

Melon-louse, /ife history, 126.
Melophagus ovinus, 369.
Membracidae, defined, 138.
Mosothorax, 23.
Mesograpta polita, 350.
Metathorax, 23.
Metamorphosis, defined, 48.
Microcentrum retinervis, 94.

laurifolium, 94, 95.
Microgaster, 383.
Micro-lepidoptera, 310.
Micropyle, defined, 47.
Midaidae, 344.
Midges, 334, 336.
Migration in plant-lice, 126.
Milk-weed butterfly, 242.
Mineola indiginella, 313.

vaccinii, 313.
Mole-crickets, 98.
Monilicornia, defined, 165.
Moniliform antennae, 22.
Monomorium pharaonis, 396.
Monophadnus rubi, 374.
Monostegia rosae, 374.
Mormon cricket, habits of, 97.
Mosquitoes, 332.
Mosquito-hawks, 61.
Moths, chapter on, 240.
Moulting of insects, 48.
Moults, number of, 49.
Mourning-cloak butterfly, 244.
Mouth of bees and wasps, 19.

importance of, 14, 16.

indicates remedies, 16.

of flies, 18.

types of, 14.
Mud-daubers, 402.
Multicellular gall, 378.
Murgantia histrionica, 162.
Muscidae, 353, 356.
Muscles, structure and character, 28.
Mushroom-gnat, 334.
Mutillidae, 400.
Mycetophilidae, 334.
Myrmecocystus melliger, 396.
Myrmeleonidae, described, 75.
Myrmicidae, 396.
Mytilaspis pomorum, 115.
Myzus cerasi, 134.

476

INDEX.

Nabidae, defined, 153.

Nabis fusca, 154.

Naphthaline against book-lice, 69.

and its uses, 452.
Natural checks to insect increase, 418.
Necrophorus, 171.
Negro-bug, 163.
Nematus ribesii, 372.
Nervous centre in flies, 41.

system of insects, 39.
Neuroptera, defined, 53, 54.

chapter on, 58.

described, 72.
Neuters in ants, 391.
Newspaper barriers against borers, 431.
Nisoniades, species of, 254.
Nitidulidae, 181.
Nits of lice, 105.
Nixon nozzles, 458.
Noctuidae, 288.
Notodontidoe, 275.
Notolophus leucostigma, 268.
Nozzles, types of, 456.
Nut-weevils, 234.
Nymph, defined, 49.
NymphalidfE, 242.

Oak, Edema albifrons on, 277.

galls, 377.

leaf-rollers, 321.

orange-striped worm on, 278.

pruners, 207.
Ocelli, described, 41.

location of, 22.
Ocneria dispar, 270.
Odonata, described, 60.
Odontota dorsalis, 222.
CEcanthus species, 100.
Qidemasia concinna, 277.
CEdipodinpe, described, 87.
OEsophagus, described, 30,
CEstridse, 351.
Qistrus ovis, 352.
Olfactory organs, described, 44.
Olfersia, species, 369.
Oncideres species, 210.
Onion maggot, 363.

thrips, 102.
Ophion species, 382.

Orange, Aleyrodes on, 122.

cottony- cushion scale, 108.

-dog, 253.

mealy-bugs on, 106.

oyster-shell scales on, 116.

red-bug on, 157.

Termite attack on, 67.
Orange-striped oak-worm, 278.
Orbicular spot, 289.
Orchelimum species, 96.
Orcus, 174.

Orders of insects, 52, 54.
Orgyia leucostigma, 268.
Ortalids, 365.
Orthoptera, chapter on, 79.

defined, 53, 54.
Orthosoma brunneum, 206.
Ovaries, described, 46.
Oviduct, described, 46.
Oviposition of Acridiidag, 89.

Chrysopa, 74

dragon-flies, 62.

field-crickets, 99.

grasshoppers, 89.

katydids, 96.

locusts, 94.

tree-crickets, 100.
Ovipositor, described, 46.

in crickets, 97.

of parasites, 379.
Owlet moths, 288.
Ox-louse, 104.
Ox-warble, 352.

Oxyptilus periscelidactylus, 318.
Oyster-shell bark-lice, 115.

Pain in insects, 40.
Pale-striped flea-beetle, 221.
Paleacrita species, 308.
Palm-weevil, 236.
Palpi, structure and function, 16.
Pamphila, species of, 254.
Panorpidas, described, -]•].
Paper-making wasps, 406.
Papilio asterias, 250.

cresphontes, 253.

philenor, 251.

turnus, 252.
Papilionidae, 246.

INDEX.

477

Papilioninae, 250.
Parasites on plants, 377.
Parasitic hymenoptera, 379.

insects, chapter on, 418.
Parasitica, defined, loi, 103.
Paria aterrima, 212.
Paris green, analysis of, 434.
Paroxya, 90.

Parthenogenesis in plant-lice, 123.
Passalus cornutus, 197.
Pea-weevils, 223.
Peach-borer, 261.

-louse, 134.
Peacock-flies, 365.
Pear-midge, 339.

-psylla, life history, 137.

sinuate borer in, 187.

-slug, 372.
Pectinated antennae, 21.
Peddlers, 222.
Pediculus species, 103.
Pelecinus polyturator, 389.
Pelidnota punctata, 202.
Peloposus species, 402.
Pemphigus, described, 132.
Penis of insects, 47.
Pentatomidse, defined, 162.
Pentilia misella, 174.
Pepsis species, 401.
Perception, sense of, 45.
Periodical cicada, 140.
Periplaneta orientalis, 82.
Perlidae, described, 64.
Pernicious scale, 118.
Persian insect powder, 442.
Pezotettix, 91.
Phasmidae, described, 84.
Philampelus achemon, 258.

pandorus, 258.
Phorbia brassicae, 361.

ceparum, 363.
Phosphorus against roaches, 82.
Photinus pyralis, 190.
Phthirius inguinalis, 105.
Phycitinae, 312.
Phyllodromia germanica, 82.
Phyllcscus flaviventris, 373.
Phyllotreta vittata, 221.
Phylloxera, life history, 128.

Phymata, habits of, 154.
Phyniatodes amcenus, 207.

variabilis, 207.

varius, 207.
Physopoda, 101.
Phytonomus punctatus, 229.
Phytophaga, described, 205.
Phytophagous beetles, defined, 165.
Pickle-moth, 311.
Pierinae, 246.
Pieris protodice, 248.

rapae, 246.
Pigeon tremex, 375.
I'impla conquisitor, 381.
Piophila casei, 368.
Pissodes strobi, 230.
Plagionotus speciosus, 208.
Plant-lice, defined, 123.

life history, 124.

on roots, 127.

remedies against, 135.
Planting, date of, important, 428.
Platyptera, described, 64.
Platysamia cecropia, 280.
Plecoptera, described, 63.
Pleurum or side, 25.
Ploughing, to reduce insect injury,

425-
Plum curculio, 232.
Plume-moths, 318.
Plumose antennae, 21.
Plusia brassicae, 302.

species, 302.
Podurids, 56.

Poecilocapsus lincatus, 156.
Poisers, of flies, 327.
Polistes species, 406.
Pollen basket, 408.
Pollination, due to bees, 408.
Polyphemus moth, 282.
Pomace-flies, 367.
Pompilidas, 400.
Potash as a winter wash, 450.
Potato-beetle, old-fashioned, 225.
striped, 213.
three-lined, 211.

flea-beetle, 219.

stalk-borer, 234.

scab-gnat, 335.

478

INDEX.

Potato-sphinx, 256.
Poultry-lice, 71.
Powder bellows, 455.
Praying Mantis, habits of, 84.
Predaceous bugs, 152.

insects, chapter on, 418.
Preventives, chapter on, 418, 430.
Printers-ink bands, 433.
Prionidus cristatus, 152.
Prionoxystus robiniae, 287.
Prionus laticollis, 206.
ProctotrypidDg, 387.
Prolegs, defined, 12.
Prominents, 275.
Prothorax, 23.
Protoparce Carolina, 256.

celeus, 256.
Psenocorus supernotatus, 208.
Pseudo-neuroptera, defined, 53, 54, 58.
Pseudo-trachea of fly, 20.
PsocidEe, described, 68.
Psocus lineatus, 69.
Psychidse, 273.
Psychomorpha epimenis, 264.
Psylla pyricola, 137.
Psyllidje, defined, 137.
Pteromalus puparum, 385.
Pterophoridse, 318.
Ptinidce, 193.
Pubescent antennas, 22.
Pulvilli, defined, 26.
Pulvinaria innumerabilis, no.
Pumps, for spraying, 456, 462.
Punkies, 334.
Pupa, defined, 49.
Pupipara, 369.
Pyralididte, 310.
Pyralis farinalis, 312.
Pyrausta species, 311.
Pyraustidos, 310.

Pyrethro-kerosene emulsion, 443.
Pyrethrum and its uses, 442.
Pyrophila pyramidoides, 299.
Pyrrharctia Isabella, 266.

Quassia as an insecticide, 453.
Queen bees, 415.
Quince-borer, 209.
-curculio, 234.

Radish-maggot, 362.
Raphidia, 72.
Raptoria, defined, 81.
Raspberry, Byturus, 180.

-slug, 374.
Rat-tailed larvae, 350.

how they breathe, 37.
Raupenleim and dendrolene, 431.
Receptaculum seminis, 46.
Rectum, described, 30.
Red-bug on cotton, 157.

-humped prominent, 277.

-legged locust, go.

-necked cane-borer, 186.
Reduviidce, defined, 151.
Reflowing cranberry bogs, 428.
Regal walnut-moth, 278.
Reniform spot, 289.
Reproduction among insects, 45.
Resin washes, use and formulas, 447.
Respiration in insects, 33.

in dragon-fly larvae, 51.

in water-beetles, 36.

economic bearing of, 33, 38.
Retina, described, 41.
Rhipiceridse, 182.
Rhizobiinse, described, 127.
Rhizobius, 174.
Rhopalocera, defined, 241.
Rhopobota vacciniana, 320.
Rhubarb, weevil on, 230.
Rhynchophora, 165, 228.
Rhynchophorus palmarum, 236.
Roaches, life history, 81.
Robber-flies, 344.
Rocky Mountain locust, 90.
Root-lice, remedies for, 130.

-maggots, 360.

web-worms, 317.
Rose-beetle, Fuller's, 228.

-bug, 199.

-chafer, 199.

leaf-hopper, 148.

leaf-rollers, 321.

-scale, 119.

-slug, 374.
Rosy Dryocampa, 279.
Rostrum, defined, 17.
Rotation, use of, 426.

INDEX.

479

Round-headed borers. 205.
Rove-beetles, 172.

Saliva and its uses, 31.
Salivary glands, 30, 31.
Saltatoria, defined, 81.
San Jose scale, 118.
Sand-crickets, 97.

-flies, 334.
Sannina exitiosa, 261.
Sap-beetles, 181.
Saperda Candida, 209.
Sarcophaga carnaria, 355.
Sarcopsylla, species of, 329.
Saw-flics, 371.
Scale insects, 106.

remedies for, 108, 120.
Scape of antenna, 22.
Scavenger beetles, 172, 197.
Scaraba^idse, 197.
Scenopinidas, 347.
Scenopinus fenestralis, 347.
Schistocerca americana, 89.

peregrinum, 89.
Schizoneura, described, 133.

lanigera, 133.
Sciara species, 334.
Sclcrites, defined, 23.
Scoliidae, 400.
Scolytidae, 237.
Scolytus rugulosus, 238.
Scorpion flies, their habits, etc., tj.
Screw-worm fly, 357.
Scudderia species, 94.
Scurfy scale, described, 119.
Scutellerida;, defined, 163.
Scymnus species, 174.
Segments in insects, 311.
Semi-loopers, 300.
Seminal receptacle, 46.
Sensation in insects, 40.
Sericaria mori, 286.
Serrate antennae, 21.
Serricornia, defined, 165.
Sesia acerni, 262.

tipuliformis, 263.
Sesiidae, 259.

Seventeen-year locust, 140.
Sex in insects, 46.

Shecp-bot, 352.

-tick, 369.
Sialidae, described, 72.
Silk-worm, 286.
Silpha species, 171.
SilphidcB, 171.
Silvanus surinamensis, 176.
Silver-fish, 56.
Simuliidoe, 341.
Sinoxylon, 193.
Sinuate pear-borer, 187.
Sitodrepa panicea, 193.
Skippers, 254.

in cheese, 368.
Slugs, beetle larvae, 211.

saw-fly larvae, 372.
Smell, sense of, 43.

organs of, in antennae, 20,
Snake-doctors, 60.
Snapping beetles, 182.
Snout-beetles, described, 228.

what are, 165.
Soap mixtures, how they kill, 38.
Soaps as insecticides, 444.
Social bees, 414.

life among Termites, 64.

wasps, 405.
Soft scales, described, no.
Soldier beetles, 191.

flies, 343.
Solitary bees, 407.
Spanish flies, 225.
Span-worms, 307.
Species, defined, 52.
Sphecidae, defined, 402.
Sphecius speciosus, 403.
Sphenophorus, species of 236.
Sphex ichneumonea, 403.
Sphingidae, 254.
Sphinx Carolina, 256.

celeus, 256.
Spilosoma virginica, 266.
Spiracles, described, 33.

how protected, 34.
Spittle insects, 146.
Spraying machinery, 456.
Spring-beetles, 182.

-tails, 53, 56.
Spotted vine-chafer, 202.

48o

INDEX.

Squash-borer, 259.

-bug, 160.

lady-bird, 175.
Stable-fly, 358.
Stag-beetles, 196.
Stagmomantis Carolina, 84.
Staphylinidas, 172.
Stem-mother in plant-lice, 123.
Stenopalmatus, 97.
Sternum or breast, 25.
Stinging Hymenoptera, 390.
Stomach poisons, how they act, 32.
Stomoxys calcitrans, 358.
Stone-flies, 63.

Stored produce. Termites in, 67.
Strategus, 203.
Stratiomyidae, 343.
Strawberry-root borers, 212.

weevil, 231.
Stridulating organs, 93.
Striped cucumber-beetle, 214.
Structure in general, 11.
Subterranean forms, breathing, 36.
Sucking lice, 103.

mouth, 17,
Sugar-cane beetle, 203.

borers, 317.

Termite injury to, 67.
Sulphur as an insecticide, 452.
Sutures, defined, 23.
Swallow-tail butterflies, 250.
Swarming of bees, what is, 415.
Sweet-potato flea-beetle, 219.
tortoise-beetles, 222.
Syrphidae, 347.
Systena blanda, 221.

Tabanidae, 342.
Tachina flies, 354.

vivida, 354.
Tactile organs, what are, 44.
Tarantula hawk, 401.
Tarred paper against borers, 431.
Tarsus, defined, 26.
Taste in insects, 43.
Tegmina, defined, 79.
Telea polyphemus. 281.
Telephorus, 191.
Tendon, described, 28.

Tenebrionidae, 224.

Tenebrioides, 182.

Tent-caterpillars, 284.

Tenthredinidae, 371.

Teras and its parasites, 420.
minuta, 319.

Termes flavipes, 65, 67.

Termites, their habits, etc., 64.

Testes, described, 47.

Tettiginse, described, 91.

Thalessa species, 379.

Thecla, species of, 245.

Thick-head flies, 351.

Thorax, structure and function, 23.

Three-lined potato-beetle, 211.

Thripidae, defined, loi.

Thrips, life history, 102.
remedies for, 102.

Thyridopteryx ephemeraeformis, 273,

Thysanoptera, defined, loi.

Thysanura, defined, 53, 54.
chapter on, 55.

Tibia, defined, 26.
Tiger-beetles, described, 166.
Time of planting, important, 428.
Tingitidae, defined, 154.
Tinea pellionella, 325.
Tineina, defined, 323.
Tiphia inornata, 400.
Tipulidae, 330.
Tobacco and its uses, 440.
against root-lice, 131.
beetle, 193.
sphinx, 256.
thrips on, 102.
Tomato fruit-worm, 303.
Tortoise beetles, 222.
Tortricids, 319.
Touch in insects, 44.
Tracheae, described, 34.
Tracheal gills, 37.
Tracheates, defined, 34.
Transformations, how observed, 50.
Trap crops, 428.
Tree-crickets, 100.
-hoppers, 138.
Tremex columba, 375.
Tribolium species, 225.
Trichobaris 3-notata, 234.

INDEX.

481

Trichogramma prctiosa, 386.
Trichoptera, defined, 77.
Triphleps insidiosus, 156.
Triungulin of meloid larva, 227.
Trochanter, defined, 26.

in parasites, 379.
Trogoderma, 179.
Trogositidoe, 182.
Trogus exesorius, 381.
lYox, 199.

Trypeta ponionella, 366.
Tryxalinae, described, 87.
Tubulifera, 390.
Tumble-bugs, 198.
Turkey-gnat, 340.
Turkeys versus grasshoppers, 427.
Tussock moths, 268.
Twig-girdlers, 207, 210.
Two-striped tortoise beetle, 222.

Under-sprayers, 461.
Uroceridae, 371, 374.

Vagina, described, 46.
Valves of the heart, 32.
Vanessa antiopa, 24^.
Vaporer moths, 268.
Vapors as insecticides, 450.
Vedalia cardinalis, 173.

versus Icerya, 421.
Velvet ants, 400.
Venation, defined, 25.
Vermipsylla, species of, 329.
Vermorel nozzle, 456.
Vespa species, 405, 406.
Vespidse, 404.
Vestiture of bees, 408.
Viviparous plant-lice, 123.

scale insects, 114.
Vision of insects, 41, 42.

Walking-leaves, life history, 85.

-sticks, life history, 85.
Washing trees in winter, 433.
Wasps arc beneficial, 407.
Water as an insecticide, 450.

-beetles, 169.

Water-boatman, 150.

-scavengers, 170.

-striders, 151.
Wavy-striped flea-beetle, 221.
Waxy scales, 108, 112.
Web-worms, 266, 311, 317.
Weevils, defined, 228.
Whale-oil soap, 445.
Wheat-head army-worm, 296.

Hessian fly in, 336.

-midge, 338.

saw-fly borer, 376.

stalk-borer, 299.
Wheel-bug, described, 152.
White ants, life history, 64.

ermine moth, 266.

-faced wasp, 406.

-grubs, 196.

-pine weevil, 230.
Whitewash, usefulness of, 422.
Whirligig beetles, 169.
Willow saw-fly, 374.
Window flies, 371.
Winglet, defined, 366.
Wings, number and location, 12.

structure of, 25.
Wings of the heart, 33.
Winter washing of fruit-trees, 433.
Wire netting against borers, 430.
Wire-worms, crane-fly larvae, 331
described, 182.
remedies for, 184.
Woolly apple-louse, 133.

bears, 265.

plant-lice, 133.
Worker-ants, 391.
Wrigglers, 332.

Xiphidium species, 96.
Xylina antennata, 300.

species, 300.
Xylocopa virginica, 412.
Xyloryctes, 203.

Yellow-jackets, 405.

-necked caterpillar, 275.

Zeuzera pyrina, 287.

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