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                    U. S. DEPARTMENT OF AGRICULTURE

                      FARMERS' BULLETIN No. 1346

                            CARPET BEETLES
                               AND THEIR
                                CONTROL

CARPET BEETLES, or so-called "buffalo moths," are common household
pests usually associated in their destructive work with clothes moths.
Ordinarily they are not so destructive as clothes moths, because they
reproduce only once a year, and then not so abundantly.

Experienced housewives throughout the North are familiar with the
stout, oval, reddish-brown, hairy grubs or larvæ of the common carpet
beetle, found beneath carpets or in clothing. In southern homes,
however, the longer, slender, golden-brown larva of the black carpet
beetle, with its tuft of golden bristles, is more common.

All carpet-beetle larvæ feed upon fabrics or upon various articles,
including upholstered furniture, containing wool, silk, hair, fur,
bristles, or feathers. They even feed upon dried animal matter.

Protection against carpet beetles can be secured in tight chests and
trunks by the use of the crystals of naphthalene, paradichlorobenzene,
or camphor, or by the fumigants carbon disulphid and carbon
tetrachloride Where infestation is general throughout a house
or is serious in closets, it may be advisable to fumigate with
hydrocyanic-acid gas, carbon disulphid, or sulphur, but none of these
fumigation methods should be employed except by a person well informed
regarding them. The foregoing remedies and others, such as cold
storage, red-cedar chests, heat, and the treatment of infested floor
cracks, are discussed in this bulletin.

Washington, D. C.

July, 1923

CARPET BEETLES AND THEIR CONTROL.

By E. A. Back, _Entomologist in Charge of Stored-Product Insect
Investigations, Bureau of Entomology_.

CONTENTS.

                                              Page.

  Carpet beetles or "buffalo moths"              1
    The common carpet beetle                     2
    The black carpet beetle                      4
    The varied carpet beetle                     6
    The furniture carpet beetle                  7
  Control measures                               9
    Naphthalene                                 10

                                              Page.

  Control measures--Continued.
    Paradichlorobenzene                         10
    Camphor                                     10
    Red-cedar chests                            11
    Cold storage                                11
    Fumigation                                  11
    Miscellaneous control measures              12

CARPET BEETLES OR "BUFFALO MOTHS."

THE so-called "buffalo moths" are not moths; they are beetles and
very distinct from the true clothes moths. In this country there are
six species,[1] at least, that attack museum materials and household
fabrics, but of these only four[2] have proved serious household pests
in America. All species are capable of subsisting upon dried animal
remains, and thrive upon them perhaps as well as upon the fine fabrics
of wool, hair, feathers, fur, and silk.

[1] _Anthrenus scrophulariae_ L., _A. museorum_ L., _A. fasciatus_
Hbst., _A. lepidus_ LeC, _A. verbasci_ L., and _Attagenus piceus_ Oliv.

[2] _Anthrenus scrophulariae_ L., _A. verbasci_ L., _A. fasciatus_
Hbst., and _Attagenus piceus_ Oliv.

Carpet beetles pass through life cycles, or generations, consisting
of egg, larva or grub, pupa, and adult or beetle. These stages
differ greatly in appearance. The beetles are broadly oval and about
three-sixteenths to one-fourth of an inch long; black, but with this
blackness often obscured by tiny red, orange, brown, yellow, or white
scales which form color designs characteristic of the species. These
scales, which are modified hairs, are easily rubbed off, revealing the
black color of the body beneath. The larvæ, or grubs (as the larvæ of
beetles are often called) are brownish or black and variously clothed
with stiff hairs, as shown in Figures 1 and 8, or with a long tuft of
hairs at the end of the body, as shown in Figure 5. Carpet beetles
pass through not more than two generations annually, and more often
only one, and there are records of certain individuals requiring much
longer, even three years, to complete their growth. The following
accounts are given of the four most important species.

THE COMMON CARPET BEETLE.[3]

[3] _Anthrenus scrophulariae_ L.

The common carpet beetle was known as _the_ carpet beetle in the years
following its introduction into America when floors were more commonly
than, now covered entirely with carpets that were tacked down along the
edges, thus giving the larvæ an undisturbed shelter favorable to their
development. Originally a pest in Europe, where it is still common, it
was introduced into this country about 1874, probably at Boston and New
York simultaneously. No stage of this common carpet beetle is longer
than three-sixteenths to one-fourth of an inch. The general proportions
of larva, pupa, and adult are shown in Figure 1. The rich reddish brown
larvæ are clothed with stiff dark brown hairs which are longer around
the sides, and still longer at the ends, than upon the back.

[Illustration: Fig. 1.--The common carpet beetle: _a_, Larva, dorsal
view; _b_, pupa within larval skin; _c_, pupa, ventral view; _d_,
adult. All enlarged (Riley.)]

The larvæ feed upon carpets and woolens (Fig. 2), furs, feathers (Fig.
3), bristles, and silks. They remain secluded in dark places, hidden
beneath carpets or in the folds of garments. They eat irregular holes
in fabrics, but in carpets tacked to floors they are more likely to eat
slits following cracks. They never cause a webbing on the fabric.

[Illustration: Fig. 2.--Typical carpet beetle damage to woolen cloth.
For injury to feathers see Fig. 3.]

While most conspicuous in the Northern States, this carpet beetle is
frequently found in the latitude of Washington, D. C, and southward
Specimens have, recently been sent from Texas and Florida. In a
Washington storehouse the contents of a trunk closed for several years
were found badly damaged by the larvæ.

The following account[4] is just as applicable to-day as when written
many years ago.

[4] Howard, L. 0., in Bulletin 4, new series, Division of Entomology,
United States Department of Agriculture, pp. 58-59. 1896.

 The adult insect is a small, broad-oval beetle, about three-sixteenths
 of an inch long, black in color, but is covered with exceedingly
 minute scales, which give it a marbled black-and-white appearance.
 It also has a red stripe down the middle of the back, widening into
 projections at three intervals. When disturbed it "plays 'possum,"
 folding up its legs and antennæ and feigning death As a general thing
 the beetles begin to appear in the fall, and continue to issue, in
 heated houses, throughout the winter and following spring. Soon after
 issuing they pair, and the females lay their eggs in convenient spots.
 The eggs hatch, under favorable conditions, in a few days, and the
 larvæ, with plenty of food, develop quite rapidly. Their development
 is retarded by cold weather or lack of food, and they remain alive
 in the larval state, in such conditions and particularly in a dry
 atmosphere, for an almost indefinite period molting frequently and
 feeding upon their cast skins. Under normal conditions, however the
 skin is cast about six times, and there are, probably, in the North,
 not more than two annual generations. When the larva reaches full
 growth the yellowish pupa is formed within the last larval skin.
 Eventually this skin splits down the back and reveals the pupa,
 from which the beetle emerges later. The beetles are day fliers,
 and when not engaged in egg laying are attracted to the light. They
 fly to the windows, and may often be found upon the sills or panes.
 Where they can fly out through an open window they do so, and are
 strongly attracted to the flowers of certain plants, particularly
 the family Scrophulariaceæ but also to certain Composite, such as
 milfoil (_Achillea millefolium_). The flowers of Spiræa are also
 strongly attractive to the beetles. It is probable, however, that this
 migration from the house takes place, under ordinary circumstances
 after the eggs have been laid.

[Illustration: Fig. 3.--Feathers damaged by fabric pests. Injury
has been done here by clothes moths and carpet beetles. They reduce
feathers to a mat-like mass.]

In Europe the insect is not especially noted as a household pest,
probably owing to the fact that carpets are seldom tacked down. In
fact, the writer believes that only where carpets are extensively used
in this way are the conditions favorable for the great increase of this
insect. Carpets once tacked down are seldom taken up for a year, and in
the meantime the insect develops uninterruptedly. With the more general
use of polished floors, and rugs which are often taken up and beaten,
there is little doubt that the "buffalo bug" will eventually cease to
be a household insect of importance. The insect is known in Europe as
infesting museums, but has not acquired this habit to any great extent
in this country. It is known to have this habit in Cambridge, Mass.,
and Detroit, Mich., as well as in San Francisco, Calif., but not in
other localities. In each of these three cases it was imported from
Europe in insect collections.

THE BLACK CARPET BEETLE.[5]

[5] _Attagenus piceus_ Oliv.

The black carpet beetle derives its common name from the black,
unadorned color of the adult. Its larva is reddish or golden brown,
long and slender, with a characteristic tuft of long hairs at the end
of its body. It curls up and "plays 'possum" when disturbed. A glance
at Figure 5 will be sufficient for the identification of this unique
carpet-beetle larva.

[Illustration: Fig. 4.--Black carpet beetle: Dorsal view of adult
beetle. Greatly enlarged.]

Widespread in Europe and Asia, it first attracted attention in America
in 1854. Since then it has become widely distributed throughout the
United States, often being the most injurious of the carpet beetles,
especially in the more southern States. It is the carpet beetle most
commonly referred by housewives to the department for identification.
It feeds upon household fabrics of wool, feathers, fur, hair, and silk,
and also upon cereals and cereal products, seeds, and dried animal
remains, hence has many opportunities for existence in warehouses and
barns as well as in houses.

=The adult.=--The adult of the black carpet beetle is small, oval, and
black, as shown in Figure 4. The adults are present in abundance only
during the early summer. In a steam-heated building at Washington, D.
C, large numbers of adults were present late in April and during May,
but became rather scarce during the first part of June, although single
adults were found as late as early in July. The adult flies readily and
is often seen crawling on window panes and screens. It is during the
adult stage that the black carpet beetle spreads most easily from house
to house.

The female beetle lays small, white, fragile eggs upon fabrics, in
floor cracks, or in any sheltered spot near its food. The length of
life of the parent insect ranges from 3 to 35 days during April, May,
and June. Seldom are adults found later than July, except in very warm
storage houses.

=The egg.=--The fragile white eggs are very seldom seen, and hatch in
warm weather in about 6 to 10 days.

[Illustration: Fig. 5.--Black carpet beetle: Larval skin showing the
typical shape of the larva and the long tuft of bristles at the end of
the body. Greatly enlarged.]

=The larva.=--The golden brown larva, with short, stiff body hairs,
and its long tuft of hairs at the end of the body (Fig. 5), attains a
length of one-fourth of an inch, exclusive of the tuft of hair at the
end of the body. When first hatched it is almost microscopic in size,
but increases rapidly under favorable food and climatic conditions.
As it grows it sheds its skin from five to eleven times, and possibly
oftener. This is of interest, for frequently the cast skins are
mistaken for the insect itself, thus unnecessarily alarming the
housewife concerning the abundance of this carpet beetle. It required
approximately one year for larvæ to become fully grown when fed upon
casein. Larvæ hatching during early June and fed upon casein became
full grown and transformed to the adult stage during the following
April, May, and June. Larvæ fed upon woolen cloth and silk and flour
and meal were still only partially grown at the end of one year,
indicating that the black carpet beetle may require two years for its
development. In India it has been found that certain of these larvæ may
require from one to three years for growth.

[Illustration: Fig. 6.--Black carpet beetle: Ventral view of pupa.
Greatly enlarged.]

=The pupa.=--In the pupa stage the insect is white, clothed with fine
white hairs (Fig. 6), and helpless. The pupa stage continues from 6 to
16 days during early summer at Washington, D. C, and is seldom found at
any other season of the year.

=Seasonal history.=--Since the greater part of the life cycle is passed
in the larva stage, the facts previously mentioned indicate that the
black carpet beetle may have only one generation each year, although
it may require two or three years for the same development. From the
observation of the writer, made in houses, warehouses, and in the
laboratory at Washington, there seems little doubt that a very large
percentage of the insects have one generation each year. Farther north,
or under less favorable climatic and food conditions, a generation may
require two or even three years. At any rate, the adults are on the
wing during early summer and the eggs for new infestations are laid
then.

[Illustration: Fig. 7.--The varied carpet beetle: Dorsal view. Greatly
enlarged.]

THE VARIED CARPET BEETLE.[6]

[6] _Anthrenus verbasci_ L.

The varied carpet beetle is similar in shape to the common carpet
beetle,[7] but is a trifle smaller. It is called the "varied" carpet
beetle because the color pattern on the back of the beetle varies
considerably with the arrangement of the white, brownish, and yellowish
scales. Figure 7 presents a common arrangement of the scales. The
underside of the body is thickly clothed with white scales. This insect
is a European pest now well established in widely separated parts of
the United States. It has been found more often perhaps feeding upon
seeds in museums than upon clothing, though its larvæ do attack woolen
goods, feathers, hair, and silks.

[7] _Anthrenus scrophulariae_ L.

The larvæ are not unlike other carpet beetle larvæ of the genus
Anthrenus. In Figures 8 and 9 are shown the newly hatched and the
mature larvæ. When unmutilated, they posses on each side at the end of
the body three dense tufts of bristles and hairs. If suddenly alarmed,
the larvæ erect these tufts and spread the bristles and hairs out so as
to form beautiful round balls.

[Illustration: Fig. 8.--Varied carpet beetle: Dorsal view of newly
hatched larva. Greatly enlarged.]

During late spring and early summer, when the insect transforms to the
adult stage in greatest numbers, the adults are driven by instinct to
seek the bright sunshine and the pollen of certain flowers. In this
respect they are not unlike other species of carpet beetles, the adults
of which may be found also upon flowers. Some think that Viburnum or
Spiraea bushes planted near the house will lure carpet beetles from the
house. It is probably true, however, that the beetles, before leaving
the house, lay a large percentage of their eggs, so that the attraction
the sun and flowers have for them is of so little practical value to
the householder that it is not worth while to depend upon flowers to
lure the adults from the house.

The varied carpet beetle in the adult stage flies about in tremendous
numbers. During May, 1922, the writer could capture them by the
thousands upon at least 30 species of flowers found in public gardens
in Washington, D. C. Single white roses often attracted more than 100
beetles, while a single stalk of a common herbaceous Spiraea harbored
more than 1,000 specimens. The beetles often fly in large numbers
rather high above the ground. A gentleman[8] after painting a portion
of the tin roof of his house during early May returned 24 hours later
to complete the painting, only to find that during the interim an
average of two varied carpet beetles to the square inch had become
entangled in the fresh paint. The writer observed two adults fly into
his city apartment in Washington through an open window during early
March, 1922. These flights of adults are of extreme importance to the
householder, because they emphasize how readily carpet beetles may
spread from house to house during spring and early summer. Window
screens will exclude all except the smallest specimens if they fit
tightly, but the average removable screen does not fit tightly enough
to prevent adult carpet beetles from crawling into the house between
screen and window frame.

[8] H. S. Barber.

THE FURNITURE CARPET BEETLE.[9]

[9] _Anthrenus fasciatus_ Herbst.

The carpet beetle or dermestid[10] here discussed has had no common
name, but may be called the furniture carpet beetle (Fig. 10). It,
too, is a European pest introduced into this country. It has been
reported from Algeria, Spain, Greece, southern Russia Mesopotamia, and
the East Indies It was first recognized in America during 1911, from
specimens sent the American Museum of Natural History, New York City,
from an upholsterer in Augusta, Ga. The specimen were taken from the
curled hair of furniture upholstered 12 to 15 years previous to 1911.
Investigation indicated that the hair used in this furniture came from
Russia. The pest was not again noted in America until April, 1915,
when it was found seriously damaging an upholstered chair in the White
House. Since then, particularly during the last several years, many
pieces of furniture and mattresses in different sections have been
reported badly damaged.

[10] So called because, like the other carpet beetles, it belongs to
the family Dermestidae.

[Illustration: Fig. 9.--The varied carpet beetle: Dorsal view of
well-grown larva. Greatly enlarged.]

In all instances the furniture was upholstered with curled hair and
moss, and in some cases the hair had been completely devoured by the
larvæ, in association with smaller numbers of the common carpet beetle,
the black carpet beetle, and the webbing clothes moth. (Figs. 11 and
12.)

[Illustration: Fig. 10.--The furniture carpet beetle: _a_, Well-grown
larva; _b_, larval skin; _c_, pupa within larval skin; _d_, two
beetles.]

This beetle is now well established in this country and is a most
serious furniture pest. The adults eat holes through heavy leather
and linen coverings, while the larvæ reduce the hair used in the
upholstering to a mass of cast larval skins and ground-up hair.
The hair then has the appearance of black gritty dirt which can be
scraped up by the handful, if not by the pailful. When the larvæ
become abundant in a piece of furniture they may drop to the floor
and there feed upon rugs and other fabrics made of wool, hair, fur,
or feathers. The larva; or grubs are seldom seen unless searched for,
but the adults, because of their habit of flight during March to June
(in Washington), leave the furniture and crawl about the furnishings
and windows, and while hardly one-fourth of an inch long, are made
conspicuous by the brown, white, and yellow scales that cover their
bodies.

[Illustration: Fig. 11.--Upholstered furniture sometimes harbors
thousands of clothes moths and carpet beetles without showing evidence
of their feeding until they have become very abundant. From this couch
thousands of adult carpet beetles were found emerging, and spreading
about the house. Only reupholstering or fumigation will rid such a
piece of furniture of pests.]

For a general impression of the appearance of the furniture carpet
beetle see Figure 10. The adult may live several weeks. The female
has been known to lay as many as 36 eggs in one day. Fortunately this
species does not seem to be very prolific, since no adult has been
known to lay more than 85 eggs. The eggs are small, white, easily
crushed by brushing, and are laid in the nap of clothing. In furniture
coverings of mohair, plush, and similar materials the eggs are tucked
down in the pile, as shown in Figure 13. The eggs hatch during warm
summer weather in from 12 to 15 days. The larvæ require the rest of the
year for growth and do not transform to the adult until the following
spring. The larvæ, however, do not all grow equally well, and some
specimens may require only one year for development, while others may
remain for considerable periods somewhat dormant, even in the presence
of much food, and will not transform to the adult until much later,
sometimes as long as one year after others, hatching on the same day,
have matured.

[Illustration: Fig. 12.--Leather covering at end of couch shown in
Figure 11, loosened to expose the work of the furniture carpet beetle.
Note that this pest, working with fewer numbers of clothes moths and
black carpet beetles, has eaten nearly all the curled hair stuffing,
leaving behind the moss used with the hair, countless larval skins, and
handfuls of a fine, gritty, dirtlike substance which is nothing more
nor less than the frass of the insect. Thousands of carpet beetles can
mature in such furniture without the knowledge of the casual observer.
It is only when the stuffing is eaten away and the pests leave the
furniture and crawl about the house that suspicion is centered upon
furniture as the possible source of an unending supply of clothes moths
and carpet beetles that appear here and there about the house.]

CONTROL MEASURES.

The measures to be used for the control of carpet beetles depend upon
the place in the house where the pest is causing injury. If carpet
beetles are troublesome in trunks, chests, or closets that are not
opened often, a good grade of flake naphthalene, paradichlorobenzene
or camphor will give good results. If the trouble is in closets in
daily use, beneath carpets or rugs, or in piano felts or upholstered
furniture, these substances are of practically no value, and one must
fumigate the house as a whole or in part with either hydrocyanic-acid
gas, carbon disulphid, or carbon tetrachlorid, or use the still older,
more tedious, and less effective means of control consisting in
frequent search for and the killing of the individual larvæ and adults,
and the treatment of floor cracks and similar hiding places with
kerosene, gasoline, or benzine. The following materials and methods may
be employed with satisfactory results:

[Illustration: Fig. 13.--Eggs of the furniture carpet beetle laid in
the pile of a plush mohair covering of a chair. Considerably enlarged:
the eggs are smaller than the head of a common pin and white In color.]

NAPHTHALENE.

Naphthalene in the form of flakes (preferably) or moth balls is
effective when used at the rate of one-half to 1 pound to each 10 to 13
cubic feet of space. It is always better to use a larger rather than
a smaller quantity of these crystals Great care should be exercised
to keep tightly closed the trunks or chests of clothing with which
the naphthalene is stored. Naphthalene in chests opened frequently or
those carelessly left open for hours at a time, or in chests with large
cracks or warped covers, is not to be depended upon. Naphthalene should
be of good grade. It is best to purchase it put up in unbroken tin cans
of 1 pound or more capacity. Remember that naphthalene kills all stages
of the carpet beetles by means of the fumes given off during the slow
evaporation of its crystals and it is essential that these fumes be
closely confined. Naphthalene in bureau drawers, in closets frequently
used, scattered upon closet shelves, or beneath carpets is not to be
depended upon for absolute protection.

PARADICHLOROBENZENE.

Paradichlorobenzene crystals are similar in general appearance to
those of naphthalene. The fumes given off by the slow evaporation of
the crystals in a tightly closed container will kill all stages of the
carpet beetle, if about 1 pound of crystals is used for each 10 cubic
feet of space.

CAMPHOR.

Camphor is not as quickly effective against all stages of carpet
beetles as are naphthalene and paradichlorobenzene. Its action is
slower. Use from one-half to 1 pound for each trunk of about 10 cubic
feet capacity.

RED-CEDAR CHESTS.

Chests made of red cedar, popularly known as Virginia[11] or Tennessee
red cedar, if well constructed, will kill the very young larvæ of
carpet beetles. They will not kill the beetles, the older larvæ, or
the pupae, nor will they prevent the eggs from hatching. The writer
has known larvæ of the black carpet beetle[12] to remain apparently
unaffected in a red-cedar chest from June of one year to May of the
following year, and then to transform normally to the adult stage. The
older larvæ of carpet beetles can be removed from clothing before it
is stored in chests by thorough brushing. It is valuable to know that
red-cedar chests will kill the very young larvæ. It should always be
remembered that articles such as balls of yarn, floor skins backed
with woolen cloth, pillows stuffed with hair or feathers, and similar
objects in the interior of which the older carpet-beetle larvæ can hide
should not be placed in cedar chests until fumigated to kill the larvæ
hidden where they can not be reached by brushing.

[11] _Juniperus virginiana._

[12] _Attagenus piceus._

COLD STORAGE.

One of the safest methods of preventing loss through carpet-beetle
attack is to store susceptible articles with a reliable cold-storage
firm maintaining rooms for such purposes at a temperature of 50° F. or
lower.

FUMIGATION.

Carpet beetles, as well as all other household pests, can be eliminated
as disturbing factors by fumigation within as short a time as three
or four hours (if necessary). Fumigation with formaldehyde candles,
although excellent for killing disease germs, is worthless for insect
control, and the public is warned accordingly. Sulphur fumes will kill
many carpet beetles, but very few persons succeed in killing all carpet
beetles with sulphur fumes. Sulphur should be burned at the rate of 13½
ounces per 1,000 cubic feet of space. It is likely to bleach wall paper
and fine fabrics and tarnish metals, and should never be used unless
one is aware of these possible bad results.

=Hydrocyanic-acid gas.=--Hydrocyanic-acid gas is the best gas known and
in present use for the fumigation of houses, or parts of houses, for
the speedy elimination of carpet beetles or other pests. When persons
are troubled with fabric pests that have become generally established
throughout the house, nothing will give greater satisfaction in peace
of mind and freedom from trouble than one thorough fumigation carried
on by a professional fumigator or by any intelligent, careful person
capable of following directions. Hydrocyanic-acid gas is dangerous
to human beings, but is noninflammable and nonexplosive as used in
household fumigation as here advocated. It is lighter than air, will
injure no fabric or painting, and will not tarnish household metals. If
properly used, it is one of the simplest and best methods of fighting
house pests. Interested persons can have full particulars free of cost
by writing the Division of Publications, Department of Agriculture, for
Farmers' Bulletin 699.

=Carbon disulphid.=--Carbon disulphid is a fumigant in general use
for killing insects of all sorts in containers that are reasonably
tight. It is excellent for killing carpet beetles in chests, trunks,
and closets that can be closed and sealed. It has been used for the
fumigation of entire buildings when these are detached. It is purchased
at drug stores or of chemical firms as a liquid put up in tin cans
containing 1, 2, 5, or 10 pounds each. Upon exposure to the air, the
liquid evaporates, forming a gas heavier than air which sinks through
the container being fumigated and kills the insects by suffocation.
The gas is explosive in the presence of fire, and must be handled with
the same care as gasoline or benzine. Although the liquid as purchased
is considered not explosive or inflammable, great care should be
exercised in storing and handling it since it is almost impossible
to dissociate it from its gas, which is, as stated above, decidedly
explosive and inflammable in the presence of fire. The odor of carbon
disulphid gas is very disagreeable, but soon disappears with the airing
of the container after fumigation. Carbon disulphid fumigation is
excellent for the destruction of carpet beetles in articles that can be
stored in trunks, chests, or closets, or for killing pests in pianos
and upholstered furniture that can be placed in a small room for the
period of fumigation. Full particulars regarding this fumigant and the
ease with which it can be used may be had by writing the Division of
Publications, Department of Agriculture, for Farmers' Bulletin 799.

=Carbon tetrachlorid.=--Carbon tetrachlorid is used in exactly the same
way and for the same purpose as carbon disulphid, except that from two
to three times as much of the liquid must be used to fumigate the same
amount of space. Carbon tetrachlorid is not a particularly effective
fumigant, but it has the advantage of producing, upon evaporation, a
gas that is noninflammable and nonexplosive, and for this reason can
be used in certain places where lighted lamps, fires, etc., can not be
entirely eliminated. See Farmers' Bulletin 799 for reference to use of
carbon tetrachlorid and carbon disulphid.

MISCELLANEOUS CONTROL MEASURES.

=Laundering and dry cleaning.=--When material infested with carpet
beetles is submerged in a solution of 1 pound of neutral soap to 10
gallons of water all stages of the beetles are killed. Carpet-beetle
larvæ are killed if subjected to temperatures of 120, 125, and 128°
F. for 30, 15, and 10 minutes, respectively. Eggs are killed when
subjected to temperatures of 125 and 130° F. for 16 and 11 minutes,
respectively Eggs and larvæ were killed in material dipped for 5 second
in water at 140° F., but submergence for the same period in water at
a temperature of 122° F. failed to kill all of them. Translated into
household terms this means that laundering clothing or other textiles
in thick suds or with water hotter than the hand can bear, or pressing
with a hot iron, will probably kill the larvæ and eggs of the carpet
beetle. The usual commercial dry-cleaning processes also are probably
effective. Unfortunately these methods are not always easily applied to
the articles most likely to be infested; they must not be considered a
preventive against reinfestation.

=Treatment of floor cracks and other hiding places.=--Carpet-beetle
larvæ often secrete themselves in the cracks of flooring, beneath
base boards, and in other openings about houses formed by the usual
shrinking or settling of woodwork. The larvæ feed upon the lint which
gathers in such places. It is, therefore, an excellent procedure to
have all such openings closed where possible by filling in with putty
or patented crack-fillers. Any cracks that can not be filled in this
manner should be periodically filled with gasoline, kerosene, or
benzine to kill larvæ. Since these liquids are inflammable, care must
be exercised not to have lighted lamps or fire in any form about until
after the rooms are well ventilated.

ORGANIZATION OF THE UNITED STATES DEPARTMENT OF AGRICULTURE.

  _Secretary of Agriculture_                   Henry C. Wallace.
  _Assistant Secretary_                        C. W. Pugsley.
  _Director of Scientific Work_                E. D. Ball.
  _Director of Regulatory Work_
  _Weather Bureau_                             Charles F. Marvin, _Chief_.
  _Bureau of Agricultural Economics_           Henry C. Taylor, _Chief_.
  _Bureau of Animal Industry_                  John R. Mohler, _Chief_.
  _Bureau of Plant Industry_                   William A. Taylor, _Chief_.
  _Forest Service_                             W. B. Greeley, _Chief_.
  _Bureau of Chemistry_                        Walter G. Campbell, _Acting
                                                 Chief_.
  _Bureau of Soils_                            Milton Whitney, _Chief_.
  _Bureau of Entomology_                       L. O. Howard, _Chief_.
  _Bureau of Biological Survey_                E. W. Nelson, _Chief_.
  _Bureau of Public Roads_                     Thomas H. MacDonald,
                                                 _Chief_.
  _Fixed Nitrogen Research Laboratory_         F. G. Cottrell, _Director_.
  _Division of Accounts and Disbursements_     A. Zappone, _Chief_.
  _Division of Publications_                   Edwin C. Powell, _Acting
                                                 Chief_.
  _Library_                                    Claribel R. Barnett,
                                                 _Librarian_.
  _States Relations Service_                   A. C. True, _Director_.
  _Federal Horticultural Board_                C. L. Marlatt, _Chairman_.
  _Insecticide and Fungicide Board_            J. K. Haywood, _Chairman_.
  _Packers and Stockyards Administration_    { Chester Morrill, _Assistant
  _Grain Future Trading Act Administration_  {   to the Secretary_.
  _Office of the Solicitor_                    R. W. Williams, _Solicitor_.

This bulletin is a contribution from

  Bureau of Entomology                       L. O. Howard, _Chief_.
    Stored-Product Insect Investigations     E. A. Back, _Entomologist
                                               in Charge_.

                           ADDITIONAL COPIES
               OF THIS PUBLICATION HAY BE PROCURED FROM
                    THE SUPERINTENDENT OF DOCUMENTS
                      GOVERNMENT PRINTING OFFICE
                           WASHINGTON, D. C.
                                  AT

                           5 CENTS PER COPY

           PURCHASER AGREES NOT TO RESELL OR DISTRIBUTE THIS
         COPY FOR PROFIT.--PUB. RES. 57, APPROVED MAY 11, 1922

              [Illustration: Upside-down triangle ▽]

                           WASHINGTON: GOVERNMENT PRINTING OFFICE: 1923

       *       *       *       *       *

Transcriber Notes

All illustrations were moved so as to not split paragraphs.


End of the Project Gutenberg EBook of USDA Farmers' Bulletin No. 1346:
Carpet Beetles and Their Control, by E. A. Back
{'title': 'Carpet Beetles and Their Control by E. A. Back', 'source': 'Project Gutenberg', 'lang': 'en'}