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- DEPARTMENT OF THE INTERIOR.

« F. V. HAYDEN, U. 8. GEOLOGIST-IN-CHARGE.

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FHEOUNITED STATES

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ON THE NATURAL HISTORY OF THE ROCKY MOUNTAIN LOCUST,
AND ON THE HABITS OF THE YOUNG OR UNFLEDGED INSECTS
AS THEY OCCUR IN THE MORE FERTILE COUNTRY IN
WHICH THEY WILL HATCH THE PRESENT YEAR.

ENTOMOLOGICAL COMMISSION.

7

3 ‘iene Oe |
cP a SECOND EDITION. "
; WASHINGTON:

GOVERNMENT PRINTING OFFICE.
June, 1877.

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DEPARTMENT OF THE INTERIOR.
U. S. GEOLOGICAL AND GEOGRAPHICAL SURVEY OF THE TERRITORIES.
F..V. HAYDEN, U. S. GEOLOGIST-IN-CHARGE.

BULLETIN

Tae UNITED STATES

ENTOMOLOGICAL COMMISSION,

ON THE NATURAL HISTORY OF THE ROCKY {MOUNTAIN LOCUST,
AND ON THE HABITS OF THE YOUNG OR UNFLEDGED INSECTS
AS THEY OCCUR IN THE MORE FERTILE COUNTRY IN
WHICH THEY WILL HATCH THE PRESENT YEAR.

INT Oo: -2:

SECON DD) H DITION:

WASHINGTON:
GOVERNMENT PRINTING OFFICE.
June, 1877.

PREFACE.

The present Bulletin has been prepared in accordance with the pur-
pose of the Commission to issue Bulletins containing special information
that is of interest and sought for at the time of publication. In prepar-
ing this Bulletin, No. 2, we have made large use of Professor Riley’s
Entomological Reports to the State of Missouri, and this the more read-
ily that they are in limited circulation outside of that State, and because
the legislature has made no provision for the distribution of the last.

The map at the end will illustrate in a general way the country that
will most severely suffer, and the eastern limit of injury the present
year. :

©. V. RILEY,

A. 8S. PACKARD, JR.,

CYRUS THOMAS,
Commissioners.

ON THE NATURAL HISTORY OF THE ROCKY MOUNTAIN LOCUST,
AND ON THE HABITS OF THE YOUNG OR UNFLEDGED INSECTS
AS THEY OCCUR IN THE MORE FERTILE COUNTRY IN WHICH
THEY WILL HATCH THE PRESENT YEAR.

CHARACTERS OF THE SPECIES.

Though often confounded with other species, the Rocky Mountain
Locust may be recognized by the following characters: It measures on
an average about 14 inches from the head to the tip of the closed wings,
and the wings extend about one-third their length beyond the tip of the
abdomen. The color is variable, but the more common specimens are
yellowish-white beneath; glaucous or cabbage-blue across the breast

Fig. 1.

Rocky Mountain Locust. RED-LEGGED Locust.

and about the mouth parts; pale-bluish, often with shades of purple, on
the sides of the head and thorax and on the front of the face; olive-
brown on the top of the head and thorax; pale beneath, more or less
bluish above and marked with black, especially toward the base, on the
abdomen. The front wings have the ground-color pale grayish-yellow,
inclining to green, and their spots and.veius brown; the hind wings,
except a yellowish or brownish shade at apex and along the front edge
and a green tint at base, are transparent and colorless, with the veins
brown. The front and middle legs are yellowish. The hind legs have
the thighs striped with pale glaucous and reddish on the outside and
upper half of inside, with four broad black or dusky marks on the upper
edge, the terminal one extending beneath around the knee. The
shanks are coral-red, with black spines; the feet somewhat paler, with
black claws; antenne pale yellow; palpi tipped with black. In the
dead specimens.all these colors become more dingy and yellow. It very
. Closely resembles, and is often

confounded with the Red-legged

Fig. 4.
Locust (Caloptenus femur-rubrum, So
De Geer), a species common tothe ~~] cp
whole middle portion of the conti- rey
W =

nent-from the Atlantic to the
Rocky Mountains, which, though — Rev-zeccrp Locusr.—
Rocky Mounraww Lo- Capable of short flights, never Fig gee ee
Soot eee of commit thesame havoc. This last and top views, of tip.
hind and top views, of tip. is, on an average, smaller, darker, with shorter aud
less conspicuously spotted wings (seldom extending more than one-
_ sixth of -their length beyond the tip of the abdomen), and the last ab-
dominal joint of the male (Fig. 4) is bluntly cut off at the top, and not

tapering and notched as in the C. spretus (Fig. 3).

6 BULLETIN U. S. ENTOMOLOGICAL COMMISSION.

THE EGGS.

The question as to how best to treat the soil or to manage the eggs so
as to most easily destroy their vitality is a most important and practi-
cal one. Everything, therefore, that relates to the eggs—the manner of
deposition, the character of the mass, the method of hatching, &c., even
to the minutest details—becomes important and is worthy of careful
study. :

WHERE THE EGGS ARE LAID.

The eggs may be laid in almost any kind of soil, but by preference
they are laid in bare, sandy places, especially on high, dry ground,
which is tolerably compact and not loose. Itis generally stated that
they are not laid in meadows and pastures, and that hard road-tracks
are preferred ; in truth, however, meadows and pastures, where the grass
is closely grazed, are much used for ovipositing by the female, while on
well-traveled roads she seldom gets time to fulfill the act without being
disturbed. Thus a well-traveled road may present the appearance of
being perfectly honey-combed with holes, when an examination will
show that most of them are unfinished, and contain no eggs; whereas a
field covered with grass-stubble may show no signs of such holes and
yet abound with eggs. Furthermore, the insects are more readily no-
ticed at their work along roads and roadsides than in fields, a fact
which has also had something to do in forming the popular impression.
Newly broken or ploughed land is not liked ; it presents too loose a sur-
face. Moist or wet ground is generally avoided for the purpose under
consideration. During the operation the female is very intent on her
work and may be gently approached without becoming alarmed, though
when suddenly disturbed she makes great efforts to get away and ex-
tricates her abdomen in the course of a few seconds, the time depending
on the depth reached.

HOW THE EGGS ARE LAID.

The female, when about to lay her eggs, forces a hole in the ground
by means of the two pairs of horny valves which open and shut at the
tip of her abdomen, and which, from their peculiar structure, are admi-

Fig. 5. rably fitted for the purpose.

(See Fig. 6, where b, ¢ show

the structure of one of each
of the upper and lower
Mm valves). With the valves
ss closed she pushes the tips

the continued opening and
shutting of the valves, she
_ drills‘a hole until in a few

minutes (the time varying
===. with the nature of the soil)
== nearly the whole abdomen
= is buried. The abdomen
stretches to its utmost for

Rocky MounTAIn BOOE a a, a, ual in ciferent posi- this purpose, especially at
tions, ovipositing; b, egg-pod extracted from ground, with the j , 7
end broken open; ¢c, a few eges lying loose on the ground; d,e, the middle, and the hole is
show the earth partially remoy ed HOF aust ate an egg-mass generally a little curved,
already in place, and one being placed; jf, shows where such a. s
Tal cailaaecatenvered'aip: and always more or less ob

PHILOSOPHY OF THE EGG-MASS. 7

lique (Fig. 5, 4). Now with hind legs hoisted straight above the back,
and the shanks hugging more or less closely the thigh, she commences
ovipositing. If we could manage to watch a female Fig. 6.
during the arduous work of ovipositing we should find
that, when the holeis once drilled, there commences to
exude at the dorsal end of the abdomen, from a pair

of sponge-like exsertile organs (Fig. 7, h) that are nor-
mally retracted and hidden beneath the super-anal ({/ any
plate (Fig. 7, 7), near the eerci, a frothy, mucous Ve
matter which fills up the bottom of the hole. Then , | Rocky = Monta
with two pairs of valves brought close together, an ters of female, showing
egg would be seen to slide down the oviduct (j) bory valves.

along the ventral end of the abdomen, and, guided by a little finger-like
style,* (g) pass in between the horny valves (which are admirably con-
structed not only for drilling, but for holding and con- Fig. 7.
ducting the egg to its appropriate place) and issue at
their tips amid the mucous fluid already spoken of.
Then follows a period of convulsions, during which more
mucous material is elaborated, until the whole end of the
bodyis bathed in it, when another egg passes down and is
placed in position. These alternate processes continue
until the full complement of eggs are in place, the num-
ber ranging from 20 to 35, but averaging about 28. The
mucous matter binds all the eggs in a mass, and when
the last is laid the mother devotes some time to filling up
the somewhat narrower neck of the burrow with a com-
pact and cellulose mass of the same material, which,

: : c E OVIPOSITION OF
though light and easily penetrated, is more or less imper- Rocky Movunrary

vious to water, and forms a very excellent protection Locust.
(Fig. 8, d).

PHILOSOPHY OF THE EGG-MASS.

To the casual observer the eggs of our locust appear to be thrust in-
discriminately in the hole made for their reception. A more careful
study of the egg-mass or egg-pod will show, however, that the female
took great pains to arrange them, not only so as to economize as much
space as possible consistent with the form of each egg, but so as to best
facilitate the escape. of the young locust; forif any of the bottom eggs
were to hatch before the upper or anterior ones, their issue would, in
their efforts to escape, disturb and injure the other eggs, were there no

ree provision against such a possi-

ae bility. The eggs are, indeed,

most carefully placed side by
sidein fourrows, each row gen-
erally containingseven. They
oblique a little crosswise of the
cylinder (Fig. 8, a). The pos-
terior or narrow end, which is-
sues first from the oviduct, is
thickened,and generallyshows
ye two pale rings around the
Ece-Mass or Rocky Mountain Locust.—a, from theside, darker tip (Fig. 9,a). This is
within burrow; b, from beneath; c, fiom above—enlargeq. pushed close against the bot-
tom of the burrow, which, being cylindrical, does not permit the outer
or two side rows to be pushed quite so far down as the two inner rows,

* This is a simple process or extension of the sternite, and may be known as the
egg-guide, or gubernaculum ovi. , .

8 BULLETIN U. S. ENTOMOLOGICAL COMMISSION.

and for the very same reason the upper or head ends of the outer rows”
are necessarily bent to the same extent over the inner rows, the eggs
when laid being somewhat soft and plastic. There is, consequently, an
irregular channel along the top of the mass (Fig. 8, ¢c), which is filled
only with the same frothy matter which surrounds each egg and occu-
pies all the other space in the burrow not occupied by the eggs. The
whole plan is seen at once by a reference to the accompanying figure,
which represents, enlarged, a side view of the mass within the burrow
(a), and a bottom (b) and top (c) view of the same with the earth which |
adheres to it removed. i

HOW THE YOUNG LOCUST ESCAPES FROM THE EGG.

Carefully examined, the egg-shell is found to consist of two layers.
The outer layer, which is thin, semi-opaque, and gives the pale cream-
yellow color, is seen by aid of a high magnifying power to be densely,
minutely, aud shallowly pitted, or, to use still more exact language,
the whole surface is netted with minute and more or less irregular hex-
agonal ridges (Fig. 9, a, b). The inner layer (the chorion) is thicker, of
a deeper yellow, and perfectly smooth. It is also translucent, so that, as
the hatching period approaches, the form and members of the embryo
may be distinctly discerned through it. The outer covering is easily
ruptured, and is rendered all the more fragile by freezing; but the in-
ner covering is so tough, that a very strong pressure between one’s
thumb and finger is required to burst it. How, then, will the embryo, |
which fills it so compactly that there is scarcely room for motion, suc-
ceed in escaping from such a prison? The rigid shell of the bird’s egg
is easily cracked by the beak of its tenant; the hatching caterpillar, curled
within its egg-sheil, has room enough to move its jaws and eat its way
out; the egg-coverings of many insects are so delicate and frail, that

the mere swelling of the embryo |

affords means of escape; those of |
others so constructed that a door —
flies open or a lid lifts by a spring |
whenever pressureis broughttobear;
in some, two halves open, as in the
Shell of a muscle; whilein a host of
\ others the embryo is furnished with a
‘Special structure called the egg-
| burster or egg-tooth (ruptor ovi), the
office of which is to cut or rupture
the shell, and thus afford means of
escape. But our young locust is
deprived of all such contrivances.
Nature accomplishes the same end
in many different ways. She is rich
in devices. The egg increases con-
siderably in size before hatching,
and the shell necessarily becomes
weaker as it stretches. At last, by
the muscular efforts of the nascent
aie locust and the swelling of its sey-
ae a Eas especialy about the head
‘ nit .,, 2nd mouth, the shell gives way, gen-

coulphtvo cf onter cuulle bata vamewerypieuy erally splitting along the eae
mas witien 1e, uae nnersbel Juctibetore hatching ventral part. All the eges ame
Bh Gry OMA WARE ANA TT given mass burst very much at one

ESCAPE OF YOUNG LOCUST FROM THE EGG. 9

and the same time, and in that event the lowermost individuals await
the escape of those in front of them, which first push their way out
through the neck of the burrow (Fig. 8, d) provided by the parent.
They all ‘escape one after the other through one small hole, which is
- searcely noticeable in the field.

Such is the usual mode of hatching; but when the young from the
lower eggs hatch first, or when the upper eggs perish and leave the
lower ones sound, as is not unfrequently the case, the exit is neverthe-
less easily made along the channel already described (Fig. 8, c).

By a series of undulating movements the nascent larva soon works
itself entirely out of the egg, when it easily makes its way along the
channel already described, without in the least interfering with the
other eggs, and finally forces a passage-way up through the mucous
filling in the neck of the burrow (Fig. 8, d). Once fully escaped from
the soil, it rests from its exertions, but for a short time only. Its task
is by no means complete; before it can feed or move with alacrity it
must molt a pellicle* which completely incases every part of the body.
This it does in the course of three or four minutes, or even less, by a
continuance of the same contracting and expanding movements which
freed it from the earth, and which now burst the skin on the back of
the head. The body is then gradually worked from its delicate cover-
ing until the last of the hind: legs is free, and the exuvium remains,
generally near the point where the animal issued from the ground, as a
little, white, crumpled pellet. Pale and colorless at first, the full-born
insect assumes its dark-gray coloring in the course of half an hour,

From this account of the hatching process, we can readily understand
why the female in ovipositing prefers compact or hard soil to that which
is loose. The harder and less yielding the walls of the burrow, the
easier will the young locust crowd its way out. ;

The covering which envelops the little animal when first it issues
from the egg, though quite delicate, undoubtedly affords protection in
the struggles of birth from the burrow, and it is an interesting fact that
while it is shed within afew minutes of the time when the animal
reaches the free air, it is seldom shed if, from one cause or other, there
is failure to escape from the soil, though the young locust may be strug-
gling for days to effect an escape.

While yet enveloped in this pellicle, the animal possesses great fore-
ing and pushing power, and if the soil be not too compact, will frequently
force a direct passage through the same to the surface, as indicated at
the dotted lines, Fig. 8,e. But it can make little or no headway, except
through the appropriate channel (d), where the soil is at all compressed.
While crowding its way out, the antenne and four front legs are held
in much the same position as within the egg, the hind legs being gen-
erally stretched. But the members bend in every conceivable way, and
where several are endeavoring to work through any particular passage,
the amount of squeezing and crowding they will endure is something
remarkable. Yet if by chance the protecting pellicle is worked off
before issuing from the ground, the animal loses all power of further
forcing its way out. The instinctive’ tendency to push upward is also
remarkable. In glass tubes, in which the eggs have been placed in
order to watch the method of hatching, the young always turned their
heads and pushed toward the bottom whenever the tubes were turned
mouth downward; while in tin boxes, where the eggs were placed at
different depths in the ground, the young never descended, even when

* This pellicle (the amnion) is common to most insects, but so far as we have observed
it is shed after leaving the chorion principally by the orthoptera and neuroptera.

10 BULLETIN U. S. ENTOMOLOGICAL COMMISSION.

they were unable to ascend on account of the compactness of the soil
above.

TIME OF HATCHING.

The date at which the eggs hatch varies with the earliness or lateness
of the spring, and is moreover quite irregular, some hatching in the same
locality when the first-hatched locusts are getting wings. As a general
rule, however, the bulk of the eggs hatch out in the different latitudes
about as follows:

In Texas, from the middle to last of March.

In the southern portion of Missouri and Kansas, about the second
week in April.

In northern parts of Missouri and Kansas and southern sections of
Iowa and Nebraska, the latter part of April and first of May.

In Minnesota and Dakota, the usual time of hatching ranges from
early in May in the southern portions to the third week in the northern
extremity.

In short, the bulk of the insects hatch, in ordinary seasons, about the
middle of March in latitude 35° and continue to hatch most numerously
about four days later with each degree of latitude north, until along
the forty-ninth parallel the same scenes are repeated that occured in
Southern Texas seven or eight weeks before.

In Montana and Manitoba, from the middle of May to the first of
June.

TRANSFORMATIONS.

When first hatched the little locust is quite pale, but soons becomes
mottled with gray and brown. Except in having a shorter, narrower
Fig. 10. prothorax, sloping roof-fashion to a me-
dian ridge, and in lacking wings, the
young locust scarcely differs in structure
from its parent; and the perfect, winged
formis gradually assumed through a series
ot five molts, during the first four of
which the wing-pads become larger, and
during the last, from the pupa (Fig. 10, ¢)
to the perfect state, the thorax becomes
flattened, the wings are acquired and the
Hey Eee Ale eae insect ceases to grow and is ready to pro-
pupa. create. The time required from hatching
till the wings are obtained averages from six weeks to two months.

In order to illustrate the interesting process of molting we will trace
an individual through the last molt—from the pupa to the winged
insect—as it is the most difficult, and on account of the larger size of
the animal, most easily watched. The other molts are very similar,
except that the wing-pads increase but moderately in size with each.
When about to acquire wings the pupa crawls up some post, weed,
grass-Stalk, or other object, and clutches such object securely with the
hind feet, which are drawn up under the body. In doing so the favorite
position is with the head downward, though this is by no means essen-
tial. Remaining motionless in this position for several hours, with
antenne drawn down over the face, and the whole aspect betokening
helplessness, the thorax, especially between the wing-pads, is noticed
to swell. Presently the skin along this swollen portion splits right
along the middle of the head and thorax, starting by a transverse-

|
\

TRANSFORMATIONS OF THE LOCUST. a0

curved suture between the eyes, and ending at the base of the abdomen.
Let us now imagine that we are watching one from the moment of this

Rocky Mountain Locust.—Process of acquiring wings; a, pupa with skin just split on the back ;
b, the imago extruding; c, the imago nearly out; d, the imago with wings expanded; e, the imago
with all parts perfect.

splitting, and when it presents the appearance of Fig. 11, a. As soon
as the skin is split, the soft and white fore-body and head swell and
gradually extrude more and more by a series of muscular contortions ;
the new head slowly emerges from the old skin, which, with its empty
eyes, is worked back beneath; the new feelers and legs are being
drawn from their casings, and the future wings from their sheaths. At
the end of six or seven minutes our locust—no longer pupa and not
yet imago—looks as in Fig. 11, b, the four front pupa-legs being
generally detached and the insect hanging by the hooks of the hind
feet, which were anchored while yet it had that command over them
which it has now lost. The ‘receding skin is transparent and loosened,
especially from the extremities. In six or seven minutes more of
arduous labor—of swelling and contracting—with an occasional brief
respite, the antenne and the four front legs are freed, and the fulled
and crimped wings extricated. The soft front legs rapidly stiffen, and, |
holding to its support as well as may be with these, the nascent locust
employs whatever muscular force it is capable of to draw out the end
of the abdomen, and its long hind legs (Fig. 11, c). This in a few more
minutes it finally does, and with gait as unsteady as that of a new-
dropped colt, it turns round and clambers up the side of the shrunken,
cast-off skin, and there rests while the wings expand and every part of
the body hardens and gains strength—the crooked limbs straightening
and the wings unfolding and expanding like the petals of some pale
flower. The front wings are at first rolled longitudinally to a point,
and as they expand and unroll, the hind wings, which are tucked and
gathered along the veins, at first curl over them.’ In ten or fifteen min-
utes from the time of extrication these wings are fully expanded and
hang down like dampened rags (Fig. 11, d). From this point on, the
broad hind wings begin to fold up like fans beneath the narrower front
ones, and in another ten minutes they have assumed the normal atti-
tude of rest. Meanwhile the pale colors which always belong to the
insect while molting have been gradually giving way to the natu-
ral tints, and at this stage our new-fledged locust presents an aspect
fresh and bright (Fig. 11, e). If now we examine the cast-off skin we
shall find every part entire with the exception of the rupture which
originally took piace on the back; and it would puzzle one who had not

12 BULLETIN U. 8S. ENTOMOLOGICAL COMMISSION.

witnessed the operation to divine how. the now stiff hind shanks of the
mature insect had been extricated from thé bent skeleton left behind.
They are in fact drawn over the bent knee-joint, so that during the process
they have been bent double throughout their length. They were as
supple at the time as an oil-soaked string, and for some time after ex-
trication they show the effects of this severe bending by their curved
appearance.

The molting, from the bursting of the pupa-skin to the full adjust-
ment of the wings and straightening of the legs of the perfect insect,
occupies less than three-quarters of an hour, and sometimes but half an
hour. It takes place most frequently during the warmer hours of the
morning, and within an hour after the wings are once in position the
parts have become sufficiently dry and stiffened to enable the insect to
move about with ease, and in another hour, with appetite sharpened by
long fast, it joins its voracious comrades and tries its new jaws. ’ The
molting period, especially the last, is a very critical one, and during the
helplessness that belongs to it the unfortunate locust falls a prey to many
enemies which otherwise would not molest it, and not unfrequently to
the voracity of the more active individuals of its own species.

_ As already stated, there are five molts exclusive of that which takes

place upon leaving the egg. In the first stage—that following the
egg—the wing-pads are not visible; in the second (after the first molt)
they project but little beyond the meso- and meta-thorax, differ but little
in size, and are directed downward, lying separately close to the body;
in the third stage (after second molt) they are directed upward, the hind
covering and hiding more or less the front pair, and the joints bear-
ing them retreating more beneath the prothorax; in the fourth stage
(aiter third molt) they are enlarged as seen in the pupa, and with the
fourth molt tbe fifth or perfect stage is attained.

HABITS OF THE YOUNG OR UNFLEDGED LOCUSTS.

The habits of the young insects as they occur in the country south of
the forty-fourth parallel are as follows: Although possessed of remark-
ably active powers from the moment they leave the egg, yet so long as
provision suffices for them on their hatching-grounds the young remain
almost stationary and create but little apprehension. As soon, how-
ever, as the supply of food in these situations is exhausted, they com-

mence to migrate, frequently in a body a mile wide, devouring as they —

advance all the grass, grain, and garden-truck in their path. The mi-
erating propensity is not developed until after the first mult. Up to
that time they are content to huddle in warm places, and live, for the
most part, on weeds, and especially on the common Dog-fennel or May-
weed (Maruta) where it is present.

The young locusts display gregarious instincts from the start, and
congregate in immense numbers in warm and sunny places. They thus
often blacken the sides of houses or the sides of hills. They remain thus
huddled together during cold, damp weather. When not traveling, and
when food is abundant, or during bad, rainy weather, they are fond of
congregating on fences, buildings, trees, or anything removed from the
moist ground. ‘They also prefer to get into such positions to undergo
their different molts.

Their power for injury increases with their growth. At first devour-
ing the vegetation in particular fields and patches in the vicinity of
their birth-places, they gradually widen the area of their devastation,
until at last they devour every green thing over extensive districts.

HABITS OF THE YOUNG LOCUSTS. 13;

Whenever they have thus devastated a country they are forced to feed
upon one another, and perish in immense numbers from debility and
starvation. Whenever timber is accessible they collect in it, and after
cleaning out the underbrush, feed upon the dead leaves and bark. A
few succeed in climbing up into the rougher-barked trees, where
they feed upon the foliage, and it is amusing to see with what avidity
the famished individuals below scramble for any fallen leaf that the
more fortunate mounted ones may chance to sever. This increase in
destructiveness continues until the bulk of the locusts have undergone
their larval molts and attained the pupa state. The pupa, being brighter
colored, with more orange than the larva, the insects now look, as they
congregate, like swarms of bees. From this time on they begin to
decrease in numbers, though retaining their ravenous propensitics.
They die rapidly from disease and from the attacks of natural enemies,
while a large number fall a prey, while in the helpless condition of molt
ing, to the cannibalistic proclivities of their own kind. Those that
acquire wings rise in the air during the warmer parts of the day, and
wend their way as far as the wind will permit toward their native home
in the Northwest. They mostly carry with them the germs of disease
or are parasitized, and wherever they settle do comparatively little
damage.

DIRECTIONS IN WHICH THE YOUNG LOCUSTS TRAVEL.

The young insects move, as a rule, during the warmer hours of the
day only, feeding, if hungry, by the way, but generally marching in a
given direction until toward evening. They travel in schools or armies,
in no particular direction, but purely in search of food—the same school
often pursuing a different course one day to that pursued the day pre-
vious. On this point the experience of 1875 is conclusive, though the
bulk of the testimony as to their actions, when hatching out in States
to the north and west, is to the effect that the prevailing direction taken
is south or southeast, while in South Texas it is just opposite, or north.
A person traveling along a road may often see them marching in one
direction to tbe left and in the opposite direction to the right.

RATE AT WHICH THE YOUNG 'TRAVEL.

When about half grown they seldom move at a greater rate than three
yards a minute, even when at their greatest speed over a tolerably
smooth and level road, aud not halting to feed. They walk three-fourths
this distance and hop the rest. Two consecutive hops are seldom taken,
and any individual one may be run down and fatigued by obliging it to
hop ten or twelve times without a rest.

THEY REACH BUT A FEW MILES EAST OF WHERE THEY
HATCH.

At the rate at which they travel, as just described, they could not ex-
tend many miles, even if they continued to travel in one direction from
the time of batching until maturity. They travel only during the hotter
portionsof the day, six hours onan average; and theirunfiedged existence
terminates in from six to eight, say seven, weeks. It is very easy to eal-
culate from these facts that if they continued in one direction from the
time they hatch until they acquire wings, they could not extend thirty
miles. In reality, however, they do not travel every day, and where
food is abundant they scarcely travel at all. Moreover, as just shown,
they do not commence traveling till after the first molt, and they do not
go continually in a particularly eastern direction, but in all directions.

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