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UNITED STATES DEPARTMENT OF AGRICULTURE

%, BULLETIN No. 1137 ¢

Vf~ Joint Contribution from the Bureaus of Plant Industry and ~\
Entomology, in Cooperation with the Ilinois, Indiana, and
Wisconsin Agricultural Experiment Stations. NH Te.

Washington, D. C. PROFESSIONAL PAPER. March 22, 1923

SYMPTOMS OF WHEAT ROSETTE COMPARED WITH
THOSE PRODUCED BY CERTAIN INSECTS.'*
By Harotp H. McKINNeEY, Assistant Pathologist, Office of Gereal Investigations.

Bureau of Plant Industry, and WaAtTerR H. LARRIMER, Scientific Assistant,
Office of Cereal and Forage Insect Investigations, Bureau of Entomology.

CONTENTS.

Page. Page.

Imbroductiony: 4 sss se" eter. we 1 | Comparison between the symptoms

Symptoms of wheat rosette________ 2 of wheat rosette and those caused
Symptoms produced by the Hessian by the wheat strawworm____-____ 6

Comparison between the symptoms Symptoms caused by the wheat stem
PB Vee me erm ey ee LS Ue ere De ese aye oa TA SS Obese en he an ae Gs

of wheat rosette and those caused Comparison between the symptoms

DyeuhesEeSSian: y= re ee 5 of wheat rosette and those caused
Symptoms produced by the wheat by the wheat stem maggot____-_~ (é
SET RE WAW GG 002 5 Sree eet Se ate ee ee Gi Conelisions iss. 2 freee See te eee fa
Mee Sa CUT ra Clie ee re ere &

INTRODUCTION.

Shortly after wheat rosette was brought to the attention of plant
pathologists, certain workers advanced the idea that the disease
was due to an infestation of the Hessian fly (Phytophaga destructor
Say) on account of certain characters manifested by the diseased
plants which resemble those of plants infested with the larve or
puparia of this insect. Although this view was not held by entomolo-
gists who were familiar with the situation, it was considered desirable
that the latter group of workers should cooperate in the investiga-
tions in order that the possibilities of an insect cause might not be
overlooked.

The writers have made observations and conducted experiments
with wheat rosette and also with a number of maladies of wheat
caused by insects which in certain stages of their development might
be confused with wheat rosette.

During 1920-21 careful observations were made on wheat plants
growing in soil infested with the causal agent of wheat rosette.
Three plats of Harvest Queen (white- chaffed Red Cross) wheat
were sown at intervals during the fall. These plats were 5 feet

-

+ This bulletin deals with the disease previously designated take-all and so-called
take-al] which occurs in Illinois and Indiana.

23244—23

~

o BULLETIN 1137, U. S. DEPARTMENT OF AGRICULTURE.

wide and 2 rods long. On November 11, after the adult Hessian flies
had ceased to fly, determinations of the percentage of fly infesta-
tion were made in all the plats by W. B. Cartwright, of the Bureau
of Entomology. In the early part of the following spriag observa-
tions were made in the same plats by Dr. R. W. Webb, of the Bureau
of Plant Industry, to d<termine the percentage of rosette infestation.
The results of these observations of infestation are given in Table it

TABLE 1.—Infestations of Harvest Queen wheat by the Hessian fly in the fall
of 1920 and by rosette in the spring of 1921 on plats near Granite City, Ill.

Plants showing infesta-
tion (per cent).

Date of sowing.

Hessian fly,| Rosette, in
in the fall. | the spring.

DPSPLeMUbo rls es Gok os SATE CEA). PRE N, G SRE TE SA es ee, Sek 2.5 | 93.6
OGtober 4s eet he eb. cee ee a eee A ee ee ee ey 0 85.6
GVCTOD CT puerta eet ets 2 a UN ee cae pee gee og cy ea pee Cag a ene ee eR 0 96.0 ~

Since rosette develops very early in the spring, before the spring
emergence of the Hessian fly adults, it is obvious that any possible
connection between this insect and rosette can involve only the fall
infestation of the Hessian fly. It will be noted from Table 1 that
there is no direct correlation between the percentage of fall Hessian
fiy infestation in any of the plats and the percentage of rosette in
the same plats the following spring. The fall fly infestation was in-
significant or absent, while the per centages of rosette were very high.
It is therefore quite evident that some other factor than the Hessian
fly is the prime cause of wheat rosette.

While all evidence indicates that the disease in question is not
caused by an insect, particularly the Hessian fly, it is recognized that.
under certain conditions there is a possibility of confusing the symp-
toms of the disease with certain of those produced by the Hessian
fly, the wheat strawworm (/Zarmolita grandis Riley), and to a less
extent the wheat stem maggot (Meromyza americana Fitch). WU
therefore seems advisable to give the chief points of similarity and
difference between the symptoms of the maladies under discussion.

The insects discussed in this paper have long been recognized as
important wheat pests, and details of their respective life histories
will not be included. Osborn (2),? Webster (5), and many others
have recorded the life history of the Hessian fly. Phillips (3) has

iven similar information concerning the wheat strawworm, and
WV Vebster (4) has discussed the life history of the wheat stem maggot.

SYMPTOMS OF WHEAT ROSETTE.

A complete description of the symptoms of wheat rosette has been
given by the senior writer in another publication (7).

FALL PERIOD.
Field symptoms—aAs this disease is interpreted at the present

time there are apparently no field symptoms in the fall. During
the past two seasons a highly susceptible variety of wheat growing

2 Serial numbers (italic) in parentheses refer to “ Literature cited” on page 8 of this
bulletin.

i Ace rl RAEN Shi SS al

SYMPTOMS OF WHEAT ROSETTE. 3

on soil of extremely high infestation appeared to be in a perfect state
of health during the autumn. While certain fungi infect the outer
tissues of the subterranean tiller parts and the subcrown internode
the general field appearance of the plants was far better than that of
varieties not known to develop wheat rosette.

Plant symptoms.—W hile the characteristic plant symptoms of the
disease do not develop in the fall, close observations and tiller counts
seem to indicate that the excessive development of tillers, which is
so characteristic of the disease in the spring, commences to a certain
extent in the autumn. However, since other important symptoms are
not associated with this fall condition, its importance as a fall symp-
tom and as an indicator of the development of the disease in the
spring is still a question.

SPRING PERIOD.

Field symptoms.—The first positive indications of the disease
become evident early in the spring after the growth of the healthy
plants is well.started. In the fields but slightly infested, distinct
patches of badly dwarfed plants show here and there without regard
to the type or condition of the soil (Pl. 1). Such patches may vary
in size from those containing but a few diseased plants to areas
many feet in diameter. Often these patches are almost circular in
shape, avhile others are irregular. It is not uncommon to find dis-
eased plants occurring singly intermixed with healthy plants. In
cases where spotting occurs, the edges of such spots are usually more
sharply defined than the margins of spots caused by unfavorable soil
conditions, especially poor drainage. In the rosette-spotted areas
most of the plants are diseased and therefore stunted right up to
the edge of the spot. In spots caused by local unfavorable soil condi-
tions all the plants usually decrease in height gradually from the
edge toward the center. |

In fields more severely infested it is not uncommon to find a large
proportion or in some eases all of the field involved. In such cases
most of the plants may be affected. There is no case on record, how-
ever, where all plants in,a large area have developed’ the disease.
Investigations have shown that apparently there are resistant strains
in the most susceptible varieties.

A striking characteristic of fields affected by the disease in the
early spring is the comparative freedom from blank spaces or area
due to dead plants. Practically all plants are intact, even though
diseased. Later in the spring, however, under certain conditions such
plants may die. During seasons of heavy rainfall diseased plants
may be washed out of the soil, causing blank areas in the field, but
this condition is rather unusual.

Plant symptoms.—Plants affected by rosette remain dormant in
the spring after healthy plants commence their spring growth. The
fall tillers of the diseased plants usually do not “ shoot,” or if they do
the process is delayed and of short duration. The leaves of diseased
plants are dark blue-green in color. They are rather broad and stiff.
Thus far, no parasites or external lesions have been found consistently
associated with the vital tissues of diseased plants during this period.

8 The term subcrown internode is used to designate the elongated region which under
certain conditions-develops between the seed and the crown of the plant.

4 BULLETIN 1137, U. S. DEPARTMENT OF AGRICULTURE.

A little later in the spring an excessive number of tillers becomes
strikingly evident, giving the diseased plants a rosette appearance
(Pl. Il, 6). Later, the underground eon of the older tillers
develops a brown. rotted condition CA, LCi.

SUMMER PERIOD.

Field symptoms.—in case of badly infested wheat fields, those
plants which -escape or resist rosette develop and form a thin
stand of grain, and the diseased plants under‘usual conditions slowly
recover by sending up straggling secondary tillers. In the case of
the early death of diseased plants, the thick tufts of plant remains
will be found on the ground usually until after harvest, except during
sseasons of heavy rainfall, when these plants are practically all
washed away.

Recovering diseased plants do not ripen until after the healthy
plants; hence, as the healthy plants turn in color. at maturity the
diseased areas show up conspicuously as green spots in the ripening,
healthy grain.

Plant symptoms.—In the case of diseased plants which do not re-
cover, their dead remains, consisting of low compact tufts of tillers
and leaves, will be found in place on the ground except where they
have been washed away. Plants which recover consist of a number
of straggling secondary culms coming tp from the stool of dead fall
tillers and leaves. Such secondary culms may or may not produce
heads. In some cases remarkable recovery occurs, especially on rich
moist soil, but usually very small imperfectly filled heads develop.
Frequently, plants are found in which only-part of the tillers are
diseased. In such cases the healthy tillers usually develop normally,
resulting in a plant consisting of a few normal tillers with dead

fall tillers at the base and perhaps a few secondary tillers attempting
to attain maturity. ;

SYMPTOMS PRODUCED BY THE HESSIAN FLY.
FALL PERIOD.

Field symptoms.—A. wheat field infested with the Hessian fly is of

a shade of green darker than normal, with a certain bristling appear-

ance due to the stiff and upright leaves of the infested plants. As
the season advances, the seemingly healthy appearance gives way
tc a more or less ragged, sickly stage, described by the farmer as
* going back.”

Under certain conditions seemingly dependent upon the response
of the wheat plant to soil variations, there may be a eee field
spotting due to fly infestation. These spots or patches are usually
associated with such conditions as soil color, type, toposraphy, and
exposure.

Plant symptoms.—tIn the case of an infested plant, the central
shoot is usually absent, and the leaves are broad, short, more or less
stiff, and of a dark-green color (Pl. I, #). By stripping down the

eaf sheath. the larva or the puparium (flaxseed) can easily be found
near the base of the plant (Pl. III, #). The presence of a single
small larva or a flaxseed is sufficient to have caused the characteristic
appearance of the wheat plant. An infested plant may produce a
few normal tillers or it may be killed, depending upon the degree of
infestation. In the latter case, as the season advances the plant

‘squetd Ayyeoy ‘Te Surpunosins oy) YIM poreduro9
se onjord oy} Jo UOMO puey-I4s IOMOT OY} UT S}ULTd posvostp oy} Jo vouLIvodde Ayo Pu JAVMP OY} OJON “JROYM JO 0440SO1 oy Aq posneo ppoy v ur 4ods [wo1dAy VW

“ALLSSOU LVAHM AO SWOLdUWAS

PLATE lI.

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Bul.

Bul. 1137, U.S. Dept. of Agriculture. PLATE II.

* Hoenn Ce Baltimore

| : =
| PLANTS OF WINTER WHEAT SHOWING THE EFFECTS OF ATTACKS OF THE ROSETTE
| AND THE HESSIAN FLY, RESPECTIVELY, COMPARED WITH HEALTHY PLANTS.

A, Healthy plant in the spring; B and C, plants of the same age as d, showing early and
advanced stages, respectively, of the rosette; D, healthy plant as it appears in the late
autumn ; £, plant of the same age as D, infested by the Hessian fly. Note the similarities
in color but the differences in the extent of tillering in plants affected by the two maladies
compared with the corresponding healthy plants.

Bul. 1137, U. S. Dept. of Agriculture. PLATE EPI.

WHEAT PLANTS INFESTED BY THE HESSIAN FLY COMPARED WITH AN
UNINFESTED PLANT.

A, B, and C, Spring-wheat plants infested by the Hessian fly; D, healthy plant of the same
age for comparison. The infested plants are much dwarfed and show the same dark-green
color in comparison with the healthy plant as is shown in Plate II, D and £. £, Winter-
wheat plants infested by the Hessian fly, showing larve (1) and puparia (2) (flaxseeds)
of the insect. The leaf sheaths have been stripped away.

PLATE IV.

Bul. 1137, U. S. Dept. of Agriculture.

“UUW VDUDINIUD DZNULOLAPY ) WOSSVUL UTOIS VEO M OY} JO (T) VAIL] OY} JO SyouqIR 9A AQ poTp[Hy ‘Furds

oy) UT Ajaeo JuRTd VRoYM-1OJUIM poJSoJul Uy ‘YF “OT [1] posejut oy) UL (g) APA oY) PUR (Z) SUTTTOMS oT[G[NG ‘poyesuoyo doyyea oy)

9)

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JON “(AOTIY, SIPUDLS DPOW ADFT ) ULIOMMBAYS PLOY AM OY} JO (T) BAIL, OY) SuLMOYsS ‘suLIds oY} UT ApAIve JURTd JVOYM-IOJUTM PojSosul UY ‘pV

“LODOVIN, WSLS LVAHM SHL GNV WYOMMVYLS LVAHM SHL Ad GALSSAN| LVSHM YSLNIM SAO SLNVId

SYMPTOMS OF WHEAT ROSETTE. 5

rapidly decays, leaving the flaxseeds more or less free in or on
the surface of the soil. This condition persists until the emergence
of the principal spring brood of the fly.

SPRING PERIOD.

Field symptoms.—In the case of extremely heavy infestation the
previous fall, practically all the plants may be killed. Varying de-
grees of infestation give the field a more or less ragged, bunchy ap-
pearance, and numerous blank spaces or areas may be evident. As
the principal spring generation begins to get in its work, the general
color of the field becomes a dark green, and growth is retarded in
accordance with the severity of the infestation.

Plant symptoms.—The effect of infestation on small plants in the
spring is practically the same as in the fall, and larve and flaxseeds
are located at relatively the same place on the culms. On larger
plants the larve or the flaxseeds may be found higher up on the stem,
but they may easily be found by stripping down the leaf sheath.
The culm may be killed or not, depending on its size and the number
of larvee or flaxseeds present.

SUMMER PERIOD.

Field symptoms.—aA thin stand with fallen straw, depending on
the severity of the infestation, usually marks an infested field in
summer. A light infestation may escape notice.

Plant symptoms.—Culms that have become weakened at the loca-
tion of the flaxseeds usually fall over before harvest. Culms that
were heavily infested may have been killed or prevented from pro-
ducing a head, but in any case the flaxseeds may be found as the cause.

COMPARISON BETWEEN THE SYMPTOMS OF WHEAT ROSETTE AND
THOSE CAUSED BY THE HESSIAN FLY.

Since rosette 1s not apparent in the autumn and since it becomes
evident in the spring before the emergence of the adult Hessian fly,
there is very little chance to confuse the two maladies during these
periods.

In the late spring there is a possibility of confusion, especially if
plants affected by rosette show, in addition, the spring infestation
of the Hessian fly.

In the latter part of the spring, fields affected by rosette sometimes
show blank areas caused by the diseased plants being washed out of
the soil by unusually heavy rains. Such fields are practically indis-
tinguishable from those suffering from a ‘severe attack of the fly,
when the infestation of either is general over the field. Owing to the

fact, however, that spring fly infestation has never been noted to
_ occur in localized areas or spots in the field, as is commonly the case
with wheat rosette, such field spotting observed at any time during
the growing season practically precludes fly injury as the sole cause,
even though all the affected plants may have been washed away.

In the case of plant symptoms, fly infestation causes a reduction
rather than an increased number of tillers, as is the case in plants
affected by rosette. While plants affected by the latter malady often
show fly infestation, it will usually be found that many near-by plants
ailected by rosette show no evidence of such infestation. In the case
of plants suffering from fly injury, the larva or flaxseed of the insect

6 BULLETIN 1137, U. S. DEPARTMENT OF AGRICULTURE,

or the empty flaxseeds will be found at the base of the plant, usually
under the first leaf sheath.

SYMPTOMS PRODUCED BY THE WHEAT STRAWWORM.
FALL PERIOD.

The wheat strawworm passes the fall and winter in the old stubble
or straw, so of course it has no effect upon the fall growth of winter

wheat.
SPRING PERIOD.

Field symptoms.—Al\most invariably the infestation by the wheat
strawworm occurs in a field bordering on old stubble or in a field
which the previous year was in wheat the stubble of which was
poorly plowed. In the first case the stand is thinner and plants
shorter next to the old stubble field, and this difference gradually
shades off to normal as the distance from the edge of the field in-

creases. This is due to the inability of the wingless form of the

insect to travel far, and for this reason most of the infestation
occurs within a strip 30 yards wide bordering on the old stubble.
Plant symptoms.—Plants infested by the strawworm resemble
those infested by the Hessian fly except that in the former case
tillering up to this time has been normal. The larve develop at
the base of the plant, causing a bulblike swelling to appear at
that point. The infested culms are always killed, and frequently all
the culms are infested. The swelling usually serves to identify the
injury caused by this insect, and of course the larve or pupe of the
insect itself (Pl. IV, A) are inside the stem, while in the case of
the Hessian fly the larva or fiaxseed is merely under the leaf sheath.

SUMMER PERIOD.

Field symptoms.—The thin stand along the old stubble field is
all that serves to mark an infested field in summer. The second
generation of the insect has enabled it to spread throughout the
-whole field.

Plani symptoms.—The decaying remains of tillers infested earlier
in the season are about all that marks the plants which have been
infested. ‘The larval form of the second generation in the straw
at this time is difficult to locate except by splitting the infested
straw.

COMPARISON BETWEEN THE SYMPTOMS OF WHEAT ROSETTE AND
THOSE CAUSED BY THE WHEAT STRAWWORM.

Wheat rosette is not confined to the vicinity of old wheat stubble
fields, as is the case with the strawworm infestation. If the former
malady occurs near such a stubble field its presence can be dis-
tinguished by means of the bulblike swelling on plants infested
with the insect; also the latter plants develop the normal number
of tillers in contrast with the excessive tillering caused by rosette.
The dead and decayed culms in late spring or autumn killed by
the first generation of the strawworm will still be recognizable by
their bulbous growth containing the refuse left by the larve of
this generation.

yy A te ee

gna

SYMPTOMS OF WHEAT ROSETTE. é 7

SYMPTOMS CAUSED BY THE WHEAT STEM MAGGOT.
FALL PERIOD.

Field symptoms.—A field infested by the wheat stem maggot has
very much the same appearance as if infested by the Hessian fly.
The stem maggot is not usually so prevalent as the fly, and in-
stances of extreme infestation are more rare. The color of an in-
fested field is a darker green than normal, and when severely in-
fested the ragged, sickly appearance comes on earlier than if in-
fested by the a fly.

Plant symptoms.—An infested plant has the center shoot dis-
colored or dead and the other leaves broader and darker green
than normal. The larva, difficult to find when small, occurs at the
base of the stem, where it lacerates the tender tissues with its mouth
hooks and feeds upon the juices.

SPRING PERIOD.

Field symptoms.—Depending upon the severity of the infestation,
gaps in the drill row caused by the dead piants mark a field infested
by the wheat stem maggot in spring; but there are so many other
causes of this same appearance that it can not be taken as charac-
teristic of this insect.

Plant symptoms.—rThe infested culms, and frequently the entire
plant, if able to withstand the injury during the fall, usually die
during the winter. Therefore, in the spring these dead and more or
less disintegrated plants contain the full-grown larve or pupe of
the insect (Pl. IV, 2).

COMPARISON BETWEEN THE SYMPTOMS OF WHEAT ROSETTE AND
THOSE CAUSED BY THE WHEAT STEM MAGGOT.

As in the case of the fall infestation of the Hessian fly, the symp-
toms produced by an infestation of wheat stem maggot in the-autumn
will not lead to confusion with rosette, even though the plants
affected by the two maladies resemble each other in certain respects.
There is practically no chance for confusing the troubles in the
spring, because the spring infestation of the maggot does not cause
symptoms which resemble the fall symptoms in any way.

CONCLUSIONS.

The insect injuries described in this bulletin may usually be
diagnosed with certainty, on account of the presence in some stage
of the insect on the affected plant. However, in the late stages of
these disorders it is sometimes difficult to find any trace of the insect,
and in such cases the infested fields and affected plants are difficult
or impossible to distinguish from fields and plants affected by rosette.

The symptoms of rosette can not be distinguished with certainty
after the spring period, and it is safer not to diagnose the disease
positively after early spring, especially if heavy rains have washed
out many diseased plants.

In the early spring the disease manifests itself by a. retarded
development of the plants, followed by excessive tillering and a dark
blue-green coloration, the leaves being broad and stiff and the whole
plant having a bunchy rosette appearance. At this time, when the
<lisease 1s not complicated with insect infestations the drill rows do
not have any blank spaces. .

Heteite: fp Meee

8 BULLETIN 1137, U. S. DEPARTMENT OF AGRICULTURE.

LITERATURE CITED.

(1) McKinney, H. H.
1925. Investigations on the rosette disease of wheat and its control.
In Jour. Agr. Research, v. 23, no. 10. [In press.]

(2) OSBORN, HERBERT.
1898. The Hessian fly in the United States. U. S. Dept. Agr., Div.
Ent. Bul. 16, n. s., 58 p., 8 fig., front., 2 pl. Bibliography, p. 48-57.

(3) PuHituies, W.-J.
1920. Studies on the life history and habits of the jointworm flies of
the genus Harmolita (Isosoma), with recommendations for control.
U. S. Dept. Agr. Bul. 808, 27 p., 8 fe 6 pl.

(4) WessTER, F. M.
1903. Some insects attacking the stems of growing wheat, rye, hanes
and oats. U.S. Dept. Agr., Div. Ent. Bul. 42, 62 p., 15 fig.

(5) 1920. The Hessian fly and how to prevent losses from it. U.S. Dept.~
Agr., Farmers’ Bul. 1083, 16 p., 13 fig.

=

ORGANIZATION OF THE UNITED STATES DEPARTMENT OF

AGRICULTURE.
SeCretary, Of Agricul tae S21 ieee ie het ee ee HENRY C. WALLACE.
ASST SiO LOS CCVCUALY, “Se ee Ci ie ns C. W. PUGSLEY.
Director of Scientific Work____—-._-_-§ ---§____ EK. D. BALL.
Director of Regulatory Work___-_~_----__-__ .
Wecuen rR ULCOME LS Rt. i Rier ae Or ehh eae CHARLES F. Marvin, Chief,
Bureau of Agricultural Economics_________~ Henry C. Taytor, Chief.
Bureau of Animal Industry_________-_____~ JOHN R. MoHteEr, Chief.
BUCOU-Of LONG INOUSbiYy Sf Ae ee ess an WiLitiAM A. TAytor, Chief.
TLOTESE SOVUUCE = tee in. ah yey ae rh eis A ae a W. B. GREELEY, Chief.
BAU RC OO TC IUCTIOUS UN ae oo are Ne Uae depose WALTER G. CAMPBELL, Acting Chief.
BRC O Us Off SOUS Ee. ee. i FE RE A Pe Sens MILTON WHITNEY, Chief.
Bureau of Entomology eta aed Og PS pea ib L. O. Howarp, Chief.
Bureau of Biological Survey__--__________- EH. W.. NELSON, -Chief.
Bureau: Of Puoue ROOds S222 SP IG THOMAS H. MacDonatp, Chief.
Fixed Nitrogen Research Laboratory_______ FE. G. Corrretyi, Director.
Division of Accounts and Disbursements____ A. ZAPPONE, Chief.
DUCVSNON, Of. LUO COLON S222 = oe ae esas JOHN L. Cosss, Jr., Chief.
TROUT pore a ORR Ger __.-_ 6 CLARIBEL- R. BARNETT, Librarian.
States Relations Sermiee_ 22 2s _ A. C. TRUE, Director.
Meera HOrniculvhiiel yBoOandas | esas C. L. MARLATT, Chairman.
Insecticide and Fungicide Board______-____ J. K. HAaAywoop, Chairman.
Packers and Stockyards il bel cee Morri11, Assistant to the
Grain Future Trading Act Administration__ Secretary.

Office -ofathie: SONCitojieee ts Sat Vey _..._ R. W. WitriaMs, Solicitor.

i

This bulletin is a contribution from the—

OE COUO FILA bl UCU GI ise aati a be SR eel WILLIAM A. TAytor, Chief.
Office of Cereal Investigations__________ CARLETON R. Batu, Cerealist in
Charge.
Bareaw of Entomology. 2 Ve th Ales eis L. O. Howarp, Chief.
Office of Cereal and F orage Insect In-
UCSTUGOLIONS. Se cae LN MS I age -W. R. Watton, Hntomologist in
Charge.

~

WASHINGTON : GOVERNMENT PRINTING OFFICE: 1923. ~ |