AGRIC, DtPT

Main Lit ENTOMOLOGY
Agric. Dept, LIBRARY

THE

HESSIAN FLY

CECIDOMYIA DESTRUCTOR

IN

GREAT BRITAIN:

BEING

OBSERVATIONS AND ILLUSTRATIONS FROM LIFE.

fy gleans of |3 rotation mt&

FROM THE REPORTS OF THE DEPARTMENT OF AGRICULTURE,
U.S.A.

BY

ELEANOE A. ORMEROD, F. R. MET. Soc.,

Consulting Entomologist of the Royal Agricultural Society of England ; Hon. and

Corr. Mem. of the Roy. Ag. and Hort. Soc. of S. Australia; Corr. Member of

the Albany Institute, U.S.A., &c.

LONDON:
SIMPKIN, MARSHALL & CO., STATIONERS' HALL COURT

1886.

PRICE SIXPENCE.
4s. per dozen ; 25s. per hundred.

H

ENTOMOLOGY
UBR3R.Y

PREFACE.

Main Lib.

Agric. Dept.

THE following pages are ail endeavour to give a
short account of the new crop-pest which has appeared
amongst us, so far as we have as yet traced its history
here. For the methods by which its ravages may be
counteracted we are under obligations to the observers,
and to the agricultural entomologists of other countries,
where these have long been studied, and especially to
those of the United States of America ; and in quoting
from their works, and to some slight extent making
use of their illustrations, I have endeavoured fully to
acknowledge the source, and also to separate these
observations clearly from the British experiences of the
past autumn.

I beg also to express my sincere thanks to the eminent
entomologists, whose names I have given in the following
pages, for their kindness in examining into and con-
firming my identification of tho attack as that of
Cecidomyia destructor at a time when the task of identi-
fication and bringing forward a crop injury never before
known in the country was a most anxious responsibility
which they assisted greatly to lighten.

E. A. 0.

THE HESSIAN FLY IN BEITAIN

IN 1886.

As far as at present appears there has been no
recorded presence of the Hessian Fly in Britain until
the latter end of July of the present year.

Those who desire to trace its history from its first
outburst as a destructive scourge in North America
during the years 1786 to 1789, with full reports of its
history, habits, gradual spread, destructive powers, and
ravages up to complete attacks of crops onwards, the
date of its first proved appearance in Europe, and the
testimony borne (up to July of the present year) of the
absence of this pest from our own country, will find
information on these subjects in the works whose titles
are quoted in the appended table.

Kelatively to the watch instituted on its very first
appearance in America lest this pest should be trans-
mitted to our own land, we find that in 1788 the wheat
crop was so much injured in various North American
localities, from which corn was then exported in large
quantities to Great Britain, that the exportation of grain
from America was prohibited until the English Govern-
ment was assured that the fly with eggs could not be
introduced in the grain* ; and next, that consequently on
the annually recurring tidings of the more and more
widely extending devastations of the Hessian Fly in
America, the investigations on this side the Atlantic
were set on foot by Sir Joseph Banks, the result of
which was, as reported by him, " that no such insect

* Bulletin No. 4 of U. S. Entomological Commission.

274356

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could be found by him to exist in Germany or any other
part of Europe."*

An alarm took place as to the arrival of the pest
about the beginning of the present century, which was
proved to be unfounded by evidence that it was another
kind of fly.f The well-known passages in Kirby and
Spence's ' Entomology ' as to the destructive character
of this pest if it gained footing give a long range
onwards of won-observation from about 1815 to the date
of the edition of 1855 ; and in 1845 John Curtis notices
the attack as one which, as it had then been detected in
Europe, it was well to mention. And, in the summary
of information given in the * Eeport on Hessian Fly,'
brought out by the United States Entomological Com-
mission, 1880-82, I find these statements: "We know
that the Cecidomyia destructor does not inhabit England
or Scandinavia. "t

Throughout this course of years we do not find any
authentic notice of the Hessian Ely occurring on our
side the Atlantic until possibly 1833 in Hungary, but
the first sure statement of the existence of the Hessian
Fly in Europe is considered to be that of " its discovery,
by Mr. J. Dana in 1834, at Mahon, Toulon, and Naples "
("Hessian Fly not imported from Europe," * Canadian
Entomologist,' 1880).

It is how known to exist in the South of France, Austria,
Hungary, and during the last seven years its presence
has been reported in Southern Russia, and its original
habitat is considered most probably to have been
Southern Europe and Western Asia, i.e., about the
shores of the Mediterranean Sea. (Report of U.S.A.
Comm., previously cited).

The past summer has shown its presence amongst our-
selves. On July 27th the first specimens of the peculiar

* Dr. B. Wagner on Hessian Fly. Keport of U. S. Entomological
Commission, 1880-82 ; Appendix I., p. 28.

t See Linn. Trans., ii., 76 - 80.

J The name of Hessian Fly was originally given in consequence of the
fly being noticed about the same time with the arrival of the Hessian
troops in America. Those who wish to see the evidence by which this

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flax-seed-like pupa were forwarded to me by Mr. G. E.
Palmer from his barley fields near Hertford, and shortly
after the attack was reported as found on other neigh-
bouring farms. On August 10th some small amount
was found at Stubbers, near Eomford, Essex, in wheat ;
on August 28th the same attack, with pupse now advanced
to the striated condition (that is, with lines running
lengthwise along them), was found at Ware ; and on
September 1st and 2nd respectively similar attack was
reported (with specimens accompanying) from barley
near Inverness, and also from barley near Crieff, Perth-
shire. In all cases the nature of the attack was identified
by sample specimens forwarded to me. Keports were
also sent me of similarly injured straw being observed
in various parts of Scotland, and that "the insect had
been observed in various counties widely apart."

On September 22nd Mr. G. E. Palmer reported that
the pupae of the Hessian Fly had been found at three
farms near Hertford, two farms near Hitchin, one near
Ware, and one near Luton, Bedfordshire. These
localities include Mr. Palmer's farm and that at Ware
previously mentioned. The observations were taken by
Mr. Palmer and Mr. H. Dorrington, residents near
Hertford, perfectly qualified to identify the attack.

Amount of injury caused by Hessian Fly attack.

It is unnecessary here to enter on the losses liable to
be caused by this attack, of which details will be found
in the works referred to in table appended. They may

transmission is thoroughly disproved will find the subject entered on at
length in a paper by Dr. Hagen, entitled, " The Hessian Fly not imported
from Europe," 'Canadian Entomologist,' October, 1880. The dates,
with names of ports of embarkation and those of arrival in America, are
there given both of the Hessian and German troops ; and (to give just
one note of the various movements specified) it will appear plain that
where troops left Hesse in February, Spithead in May, and arrived in
Sandy Hook in July, or up to August 12th, that the "flax-seeds" could
not by possibility be thus conveyed. If pupae had been in the straw (if
straw was conveyed) they would have developed long before the middle
of summer, if they were in a state to develop at all. Full details will be
found in the paper referred to.

( 6 )

be shortly stated as any amount from slight attack up
to devastation of whole large districts. Some of the
communications regarding amount of attack this year in
this country mention " the barley being very much
injured " (this on fields respectively of 33 and 15 acres) ;
" considerable damage" ; being " struck with the number
of broken-down stalks " ; and one estimate is of a
" loss of several bushels per acre " (this from one English
and three Scottish localities) ; and a general report sent
to myself mentioned the attack in Scotland as having
" been observed in various counties widely apart, and
causing considerable havoc to crops and anxiety to
farmers." Just as an example of amount of loss in the
United States, in one State, at dates widely apart, it
may be mentioned : — In New York State the loss last
year through this attack was estimated at 100,000 dols. :
in 1846 the insect was destructive through the whole
State, and the loss in the western section was estimated
at 500,000 bushels. Details of losses in various years
and localities in U. S. A. from 1776 will be found in the
Report of the U. S. A. Ent. Commission, previously
quoted.

Appearance of attacked Crops.

In Mr. Palmer's notes of the appearance of his infested
fields, he mentioned that at first he thought that the
barley was " simply root-fallen," but on closely examining
the stems he found that most of them had given way
just above the second joint from the root, and then
found that the maggot, of which the chrysalis was sent,
was the cause of the attack ; and in the report of the
attack from near Perth there is similar mention of the
broken-down stalks and small brown pupae found at the
injured part.

On examination in the fields near Hertford, on the
30th of July, I found the stems doubled sharply down a
little above the joint, as shown in fig. 1, No. 1, and between
this double and the joint below there lay, closely pressed
to the stem and covered by the sheathing-leaf, the

flax-seed-like chrysalis-cases, figured on the right hand
of the bent stem. The injury is caused by the fly-
maggots lying at the same spot sucking the juices from

No. 1. — Attacked Barley-stem ; 1, bent down ; 2, showing " flax-seeds."

the stem, which is thus weakened, and presently,
although both the stem and the ear above are more or
less stunted, yet the weakened piece of stem cannot
bear their weight, and it bends sharply down at the
injured part. Sometimes a gall or some amount of
swelling of the stem occurs just above where the maggot
fed, but in the specimens I examined this was rarely
noticeable. I am told by Mr. John Marten, of Albion,
Illinois, U. S. A., an economic entomologist who has
especially made a study of this attack, that the speci-
mens I showed him corresponded in absence of gall with
the condition of those in Illinois.

( 8 )

"Flax-seeds," Chrysalis-eases, or Puparia.
These were from one up to sometimes three or four
in number, usually only one or two ; they were invariably
set upright (not lengthwise across the stem), and some-
times, but not always, were fixed at the lower end by
being a little embedded in the straw. The " flax-seeds "
were for the most part the sixth of an inch long, of a
spindle or long oval shape, somewhat slightly flattened
on one side, and more so on the other ; the two
extremities bluntly pointed, one conical, the other,
which is the anterior end, usually slightly bent forward
with a pinch across the " flax-seed" near the end, as if
the flattened side had been bent in almost against the
other side by a nail. The colour was at first of various
shades of chestnut, from quite light to full brown, and
both in colour and in shape the cases had a strong
resemblance to the flax-seeds from which they take their
name, except in being narrower. This brown case is
the hardened skin of the maggot, and in this puparium,
or pupa-case, the maggot changes first to the pupa and
thence to the perfect fly ; at the earliest part of the
observation the transverse lines show-
ing the divisions of the segments of
the maggot were still noticeable, but
gradually, as the skin hardened, it
contracted lengthwise, and the trans-
verse lines wholly or almost entirely
disappeared, and instead of these the
eo flax-seed was marked with parallel

N°-2-—. "^ax-seeds" iineg. The first specimen in which
sfagefof'development I noticed these running along it from
nat. size and mag. one end to the other was sent me
from Ware on the 28th of August.
The figure is taken from two of my own specimens in
different stages of development at the beginning of
October.

( 9 )

Contents of the "Flax-seed," Chrysalis -case, or
Puparium.

As the attack had passed into the flax-seed state
before it was reported, I had no opportunity of observing
the maggot whilst it was still active and in feeding
condition; therefore, in order to keep the British
observations clearly distinct from those of other countries,
the description and figure of the maggot taken from
Dr. Packard's paper on the Hessian Fly is appended in
a note.* I had, however, the opportunity, by careful
dissection of a newly-formed " flax-seed," of making
out some of the points of the structure of the larva.
On opening the brown case I found the legless maggot
within still unchanged as to development ; it was bluntly
oval, with the head retracted, and it was of a white
milky colour, excepting at the divisions of the segments
and also along the central line from one extremity to
the other, which were all of a greyer tint. This
appearance is stated by Dr. Wagner to be the beginning
of the development of the adipose body, which " is dis-
tinguishable as snow-white masses from the remainder
of the more transparent body."t Beneath the maggot,
close to the head-end, was the chitinous appendage,
which is known in America as the "breast-bone" of
Cecidomyideous larvae, with us as the " anchor-process."

* " The egg is very minute, about the fiftieth of an inch long, cylin-
drical, pointed at each end, the shell shining and transparent, the egg
being of a pale red colour when the embryo is nearly
developed."

" The larva. — After remaining about four days in
the egg-state the larva or maggot of the Hessian Fly
hatches, and is of the form represented. The body
is soft, smooth, shining, oval, cylindrical, beneath a
little flattened, and consists of twelve segments
besides the head, the latter soft, fleshy, and but little
separated from the body, with very rudimentary
mouth-part8."-Hessian Fly Eeport of Department
of Agriculture, 1880 - 82, p. 208, previously cited. nat. size and mag.

The above figures of egg and larva are copied from

the same. The larva, when fairly advanced in growth, is stated by Dr.
Wagner to be white or yellowish white, transparent at the sides.

t Dr. Wagner on the Hessian Fly, Appendix I. Third Report of
United States Entomological Commission, 1880.

No. 4. — 1, anchor-
process of larva of C.
destructor ; 2, of C.
tritici (magnified).

As I am not aware that this anchor-process of the
larva of the Cecidomyia destructor has as yet been pre-
cisely figured, I give a magnified sketch from my own
British specimens. The anchor-process is a short stem
fixed at one end to the larva, and free at the other ; the
free end, which points forward, is
considerably enlarged, and is of
various form. In the " red maggot "
of our own British Wheat Midge it is
notched, as at fig. 2, No. 4, but in
the anchor-process of the Hessian
Fly the shape is more elaborate.
The stem is slightly enlarged at the
middle, and the extremity furnished
with two conical prolongations, form-
ing together a strong fork. When
seen sideways the process looks more slender, and has
a curved figure making a gentle arch from the insertion
to the forked tip.

The use of this appendage does not appear as yet to
be fully known, but from my own observations I con-
jecture that it is used as a digger or scraper, and it may
be that the reason why strong-stemmed wheat, or stems
containing more silica, are not so much injured by
attack as other kinds, is, that the fork is not strong
enough in these instances to assist the excessively deli-
cate mouth-parts to acquire their food from the stem.
The formation of the skin of the maggot is very
peculiar, and, as seen under a J-inch power,
resembles nothing so much as a nutmeg-
grater. It is covered with most minute
tubercles, each about the height of its own
width, and each with a depression or orifice
in centre. The two figs, at No. 5 give a
view sideways and from above of these
tubercles, from the dried skin of a larva
taken from the puparium with the anchor-
process attached.
About the beginning of October, on again examining

M

No. 5._Skin
of larva,
magnified.

( 11 )

the contents of a "flax-seed," I found the larva or
maggot within considerably altered. It did not as yet,
as far as I saw, show any development of limbs, but it
was now changed to a reddish yellow colour, of a
brighter red along the back. As these changes of tint
are stated by Dr. Wagner to follow almost immediately
on the rudiments of the coming wings being observable,
it is probable that examination with a better light, or
with a stronger microscope-power, would have shown
their appearance.

No. 6. — CECIDOMYIA DESTEUCTOK, Say. Hessian Fly, natural size
and magnified.*

The Imago or perfect Fly.

On the 8th of September the first fly developed from
my "flax-seeds " or puparia. This to the naked eye
was a stout-made little brown gnat, with darker head
and body, legs of rather lighter brown, brown horns,
and a pair of smoky-grey wings with longitudinal veins.
It was exactly one-eighth of an inch in length.

In order to note the successive changes in colour
occurring up to maturit}r and immediately after death,
I observed the specimen at intervals for about three
days, and endeavour to give the result as plainly as I
can. The fly was first noticed about four in the after-
noon amongst my specimens of infested straw, and I

* The position of the imago is after the fig. /. by Mr. Burgess in
plate iv. of paper on Hessian Fly in Third Keport of U. S. A. Ent.
Comm. already quoted ; the details, &c., from my own British specimen.

( 12 )

secured it by passing a long fine rod of twisted paper
just moistened at the tip with chloroform beneath it ;
this stupefied but did not quite kill it, so that I could
observe it with very slight disturbance from movements
of the insect.

About three hours after being first noticed the abdo-
men, as seen with a 1-inch power, was of various tints
of a yellow-brown colour.* The following morning, on
investigation of details, the thorax was black above,
yellow or pale yellowish brown beneath the root of the
wing, and with another patch of the same colour in
front, — that is to say, a patch about half-way down on
each side of the prothorax. The six segments of the
abdomen nearest the thorax of a raspberry colour, paler
below, with a broad black transverse band extending
over the back and half-way down the side of each
segment, which was also marked with a well-defined
black velvety patch on each side. The terminal segments
of the abdomen and the extended ovipositor were of
nearly the same shade of yellow, or pale yellowish brown
as the patches on the side of the fore body, and the ovi-
positor was not furnished with lamellulae at the extremity.
The 7th and part of the 8th segments were marked
above with a small V-shaped figure with a fine line on
each side, parallel to the sides of the V, the lowest end
of the V pointing backwards. This figure was only
noticeable when the abdomen was seen from above, and
was not of deep tint.

The halteres or poisers were of a bluntly-pointed
club-shape at the extremity, and yellow with a sprinkling
of hairs, which in some lights gave a blackish tint to the
upper part and also to the base of the club, and at this
stage there was a marking of raspberry-red just about
the middle of the poisers. The body and abdomen were
in parts very hairy, and the black velvety patches on
the sides of the abdomen appeared to be composed of

* For fuller descriptions than I can give from my own observations of
the early changes of colour the reader is referred to Dr. Wagner's paper
previously referred to.

( 13 ')

stout, black, bristle-like hairs. The two wings smoky
grey, fringed at the edges with long fine hairs, and
sprinkled over the surface with hairs, and also with
ribbed scales, resembling one of the forms found on
butterflies' wings. The wing-veins all ran lengthwise,
the first almost close to the front margin of the wing,
running parallel to it, and uniting with it about half-
way down ; the second running straight along the wing
at rather less than one-third of the whole width of the
wing from the front, until near its termination at the tip
of the wing it curved slightly backwards ; the third vein
(placed about the width above mentioned from the
hinder margin) runs almost straight, ending at the
hinder margin about one-quarter of the length of the
wing from its tip ; this third vein throws
out a side-branch, which curves backwards
to the hinder margin of the wing exactly
opposite the termination of the first vein.
Legs very long and fine, yellowish brown,
hairy ; uppermost joint of tarsi very short.
Eyes black; antennae beaded, long, and
hairy. The two basal joints shorter and No. 7.— Wing
wider than the succeeding beads. The ^ mag"*
remainder of these up to the apical joint
(with the exception of those immediately succeeding the
basal joints)* were rather longer than wide, apparently
cylindrical in form, and slightly contracted at the middle;
the terminal joint was bluntly pointed and about as
long again as the preceding bead. These joints were at
first distinctly stalked, so that, excepting towards the
end of the antenna, they could be seen to be distinctly
separated. From the minuteness of the division, and
also as with maturity and death, the beads drew so
nearly together as almost to appear to touch, I had
great difficulty in counting them, but after repeated

* I unfortunately omitted to make a note of the precise form of these
at the time ; from memory I should say they were like the corresponding
joints of the male antennas, as figured by Dr. Packard, but not having
figured and noted them at the time the observation may not be correct.

( 14 )

examination they appeared to me to be nineteen in
number, that is 2 plus 17. The colour altered with
change of condition of the specimen, but might through-
out be called brown.

The above account refers to the condition of the
specimen whilst still not quite dead, about eighteen hours
after the first observation. Twenty-four hours later the
raspberry tints were changing to shades of brown or
yellowish brown, and the black velvety patches at the
sides of the abdomen were scarcely distinguishable from
the transverse bands. The changes in colour continued,
till on the third day from the first observation the rasp-
berry tints had changed to dark brown above, lighter or
yellowish brown below, the terminal segments and the
ovipositor still retaining the original tint of yellowish
brown.

From minute examination of structure and comparison
with the descriptions and figures in the works cited,
the imago appeared to me to be without doubt the
Cecidomyia destructor of Say, commonly known as the
"Hessian Fly."

In an attack of this importance, regarding which it is
yet to be seen whether it will settle in the land as a
national scourge, or be a temporary infliction from
causes not yet made out, I in no way desired to rest
solely on my own opinion. I therefore submitted
infested straw to Professor Westwood, Life-President of
the Koyal Entomological Society, who is personally
acquainted with the insect in the " flax-seed " as well as
in the perfect state, and also forwarded others to Prof.
W. Saunders, President of the Entomological Society of
Ontario, Canada, a well-known and most sound authority
in the matter, and received from both the above referees
the confirmation that the specimens sent were without
doubt the pupae of the true Hessian Fly. On the
appearance of the imago I submitted it for special
examination to Mr. E. H. Meade, of Manningham,
Bradford, whose researches on the Diptera are too well
known to require any comment, and had from him the

( 15 )

benefit of definite opinion that it was Cecidomyia de-
structor, Say. Further, I have had the opportunity of
submitting the whole series of specimens to Mr. John
Marten, of Albion, Illinois, U.S.A., one of the economic
entomologists of Illinois, known by his papers on in-
jurious insects, published in Keports of the Department
of Agriculture, U.S.A., and whose opinion is of much
value, as having made a special study of the Hessian
Fly.

Abstract of Life-History.

The following extract from a German source* gives
the main points of the life-history of the fly in Europe
in short and plain form : —

" Cecidomyia destructor, Say. — The larvae live in the
haulm of wheat, rye, and barley. The female flies
usually lay their eggs on the young leaves twice in the
year, — in May and September, — out of which eggs the
maggots hatch in fourteen days. These work themselves
in between the leaf-sheath and the stem, and fix them-
selves near the three lowest joints, often near the root,
and suck the juices of the stem, so that later on the ear,
which only produces small or few grains, falls down at
a sharp angle. Six or eight maggots may be found
together, which turn to pupae in spring or about the end
of July, from which the flies develop in ten days." —
Stett. Ent. Zeit., xxi., p. 320.

Where does Hessian Fly come from ?

The question now arises, Where does the attack of
Hessian Fly come from ? It does not appear to have
risen up gradually in the country, as we find it widely
spread, — that is, in various parts of Scotland, as well as
in one district of England, — without any observation of
its previous presence having been reported from any
quarter, although the attack is of a kind which is very
observable, and attention is given to insect injuries to
the crops more or less in every part of the island. It

* See Die Pflanzen feinde, von J. H. Kaltenbach. Stuttgart.

( 16 )

may come in the " flax-seed " state in straw imported
from any of the countries troubled by this pest ; it may
be received from Canada, or from the United States, or
from the South of Europe, Austria, Hungary, or Kussia.

In respect to its importation in straw, it may come in
straw-cargoes, or in straw used as packing material.
Where this straw is sent forward to farms as it is, or as
slightly-used litter, or as "long" manure, quite a
sufficiently large proportion of the flies in the flax-seeds
are likely to develop to cause mischief such as we have
seen in the past season. On the first farm on which
the attack was observed near Hertford, I found on
enquiry that London manure had been used of mixed
kind, but mainly cow and horse manure in " very long "
condition.

Another way in which it is at least possible that the
" flax-seeds " may be transmitted is in wheat or barley
from infested countries. This method of transmission
is stated not to be at all likely, because the sheathing-
leaf enfolds the wheat or barley stem so tightly just
above the joint where the pupae lie that it is considered
they would not fall out in the process of threshing. But
on investigation of the attacked straw, both in the field
and after being stored away, I found it very liable to
break at the bend, and thus expose the contained " flax-
seeds " ; and on October 22nd I received information
from Mr. Palmer, of Eevell's Hall, that after threshing
some of his infested barley he examined the small seeds
and dust sifted out of the threshed corn which fell
beneath the machine, and in this he found "flax-seeds "
to the amount of fifteen in a handful of siftings. Speci-
mens of these were forwarded to me.

No pupae were found in chaff or grain. This matter
will be further investigated by observations from other
farms, and all information is solicited on the point, as it
is of enormous importance.

In cleaning seeds of the fox-tail grass from those in-
fested by Cecidomyia of another species, it is found the
infested seed, being lightest, falls at a separate spot ;

( 17 )

and, if we find that the Hessian Fly puparia fall just
below the machine customarily, there will be neither
difficulty or loss in collecting the rubbish and dirt and
destroying it.

From the above observation it appears that puparia
or " flax-seeds " may be transmitted in corn rubbish. In
samples of screenings and " sweepings " from imported
corn I have found, besides a large amount of live and
dead beetles, also weed-seeds, smut, and other matters
undesirable to spread abroad (as may easily be done
where these are used for poultry-food, and thus thrown
out in farmyards), and as, with these, broken bits of
stem are to be found, it appears at least possible that
"flax-seed" may also be conveyed. In Dr. Packard's
paper on the subject (previously quoted) he alludes to the
possibility of the pest being transmitted in wheat.

Methods of Prevention.

At present nearly all we know on this head is learnt
from agricultural publications of other countries, and
especially from the Eeports of the Agricultural Depart-
ment of the United States, but in our own country we
have one regular and constant- safeguard against autumn
attack in the fact that wheat in this country is not sown
usually until well after the time when plants may be
considered safe from eggs being laid upon them by the
autumn brood of the Hessian Fly.

This point of prevention is stated as follows in the
Third Eeport of the United States Entomological Com-
mission : " Late sowing of most of the wheat seed. All
writers, both entomological and agricultural, concur in
recommending this easily applied remedy, that at least
a part of the wheat should not be sown until after the
20th September in the Northern States."*

In this country this remedy is applied for the most
part in regular process of farming arrangements ;

* See Third Keport of United States Entomological Commission,
Department of Agriculture, p. 221, 1880 - 82.

( 18 )

commonly our wheat is not sown until some time after
date named, and thus the young plant is not up until
the flies which would have laid eggs on it are dead.

The Hessian Fly has commonly two broods in the
course of the year. The flies which come out in August
or September from the "flax-seed" chrysalis-cases,
sheltered above the second joint of the straw from the
ground (such as we have this year been troubled with in
England and Scotland), lay their eggs, we are informed
by various observers, Prof. Kiley, the State Entomologist,
amongst the number, in the grooves on the surface of
the leaves, or between the stalk and sheath where loose,
and, as soon as the footless larva or maggot hatches, it
makes its way down the leaf to the base of the sheath,
which in the young winter wheat is at the crown of the
root. Here it is stated to fasten itself lengthwise to the
tender stalk, and to move no more, but remain fixed at
one spot sucking the juices until it becomes embedded
at one extremity in the outer part of the stalk, and in
five or six weeks, according to the season, to turn to the
flax-seed chrysalis. In the case of attack to the young
wheat, the maggots drawing away the juices just near
the ground-level, cause it to turn yellow and die.

The flies from these " flax-seeds " come out in spring,
or about the beginning of May, and, as where the corn
is running up to stem the tender ground leaves are no
longer to be found, which are used for autumn egg-laying,
the flies have no choice, but they lay them instead, as we
know, so that the maggot when hatched shelters itself
between the stem and sheath just above the first or
second joint from the ground, and there it turns to the
flax-seed chrysalis, from which the autumn brood
presently come out.

To return to autumn means of prevention, as previously
said, if there is no accommodation ready for the autumn
brood, a great deal of it necessarily perishes without
egg-laying, but further (in case quite early- sown wheat
is found to be infested), by ploughing this in the maggots
and eggs will be killed ; and, in the words of Dr. Packard,

( 19 )

this brood may be circumvented or destroyed so that a
spring brood cannot appear from it.

A less expensive method of attracting the flies is the
use of what is called " bait," that is, sowing some narrow
strips of wheat to attract the flies, and ploughing this in
with the eggs and maggots ; but for ourselves the plan
arranged by Mr. G. Palmer on his farm of Eevell's Hall,
near Hertford, appears best of all as costing little or
nothing, and meeting all purposes.

Mr. Palmer showed me that on his worst infested
barley field, which was bare at the root, he had allowed
all the self-sown barley to sprout ; thus it was ready for
attack of all the flies which were hatching, or might be
hatching, out of the " flax-seeds."* When the time was
passed the plant was to be fed off by sheep, which would
eat the leaves with eggs on them, and any maggots
which had effected a lodgment in the centre of a plant
too far down to be bitten out would be effectually killed
by the subsequent ploughing coming in regular course
of operations.

The above refers to where stubbles are left ; where
they have been cut high so as to leave the infested part
standing on the field it is probably the best plan at once
to skim and collect the stubble and burn it, but from the
practical difficulties in the way of carrying out this
high cutting, and the amount of loss entailed, it does
not seem likely to be carried out.

Deep ploughing directly after cutting of stubbles
which have been infested would turn any "flax-seeds"
which had been shaken out well under, so that the flies
from them, even if they did hatch out, could not make
their way to the top. Where there is clover or seeds it
does not seem possible to do anything relatively to
attack that may very likely recur on the self-sown

* Nov. 1st, 1886. During the last few days specimens have been sent
from these plants, and shoots from old plants infested with Hessian Fly
puparia in various stages, from white condition just passing from larval
state up to regular " flax-seed." This shows that the puparia found in
the corn-stems in August, or a portion of them, do hatch out their flies
in this couutry, and confirms the need of every precaution. — E. A. 0.

( 20 )

corn, excepting what may be done to kill the young
maggots or " flax-seeds " by dressings ; for this purpose
the use of lime, salt, or soot have been recommended.

In regard to infested straw taken off the field, I am
informed by Mr. John Marten (quoted previously) that
it is found to answer well to stack this carefully after
threshing, well built up square and firm, like a hay-
stack, instead of throwing it anyhow ; thus a very great
proportion of the flies which come out of the " flax-seeds "
are destroyed, simply because they are not able to get
to the outside of the stack.

It is dimcult to see how, except on a broad scale, by
arrangement like the above we can manage to meet the
difficulty of attack spreading from infested straw. In
any common way in which it is used it is open to letting
the fly escape from it, and it is impossible without very
severe loss to destroy it. The method of saving the
straw which places the greater amount of it in a con-
dition in which it cannot spread attack, whilst being
stored for gradual use, seems worth consideration.

With regard to chaff and rubbish from the threshing,
we do not as yet know what amount of " flax-seed " is to
be found in them, and we need report from competent
inspection, so that we may know with certainty what
amount of "flax-seeds" are to be found in them. It
will be eminently desirable that infested chaff should
be mixed with wet manure, or destroyed as may be
most convenient as rapidly as possible.

One of the most important remedies or means of pre-
vention of damage is hearty growth, which will carry the
young plant through moderate attack, or, if part perishes,
will carry the other shoots on ; and another is the
choice of hard-stemmed wheat.

The evidence now coming in points to the possibility
of the " flax-seeds" being loosened, and more observa-
tions will shortly be sent in ; but meanwhile (see p. 16)
it is of the utmost importance, in threshing infested
crops, that the siftings taken from immediately below the
machine should be burnt.

( 21 )

Dressings, &c.

Lime, soot, salt, and "plaster" are mentioned as
being serviceable as dustings on young plants infested
by maggots. By plaster I am informed burnt gypsum
or plaster of Paris is intended. There appear to be
various opinions as to real benefit from these appli-
cations, and also whether they can, even when melted
by rain, reach the maggot sufficiently to destroy it ; but,
in case of any dressing being useful, it seems likely that
the mixture found serviceable many years ago by Mr.
Fisher Hobbs might answer still better, as in this the
gas-lime would take the place of the gypsum or plaster.
The mixture consists of quicklime and gas-lime, each
one bushel ; soot, ten pounds ; sulphur, six pounds ; the
whole to be well powdered and mixed and applied when
the dew is on. The above amount was sufficient for
dressing two acres of turnips as a preventive for fly, and
the quantity could be increased at discretion. This
application would in any case be useful by promoting
good growth, which is a point very much dwelt on as a
preventive of overwhelming damage from attack ; in
illustration of this point a note is given in Dr. Packard's
paper, previously quoted, regarding attack to a field of
young wheat. In the hollows on deep soil "the wheat
was very la'rge, and kept green and growing ; while on
the sharp points of knolls and hard clay ridges it was
nearly gone. On a piece of new land near by, where
never a kernel of grain was grown before, no fly or
injury could be seen." The first part of the above
observation agrees very much with what I saw on the
attacked land at RevelPs Hall. One large field of about
thirty acres at the top of the hill, and another adjoining,
which were on dry shingly soil and greatly exposed,
were much the worst attacked ; whilst another in the
hollow, which was cooler and better land altogether, had
not suffered nearly so much. Should we have the mis-
fortune of this attack settling down amongst us it will
be worth observation to find whether the fly comes worst

( 22 )

to the crops sown alone or with clover or seeds. In the
fields above mentioned the worst attacked were barley
alone ; the least attacked had clover and seeds.

Eotation of crop which excludes wheat, barley, or rye
on attacked land, is exceedingly important ; the Hessian
Ply only attacks some of the cereals, therefore all
leguminous and root-crops are perfectly safe, and like-
wise, as they cannot be used as food, help greatly in
lessening the prevalence of the pest.

The choice of kinds of corn with hard stems, such as
cannot be easily injured by the suction of the maggot,
is also particularly dwelt on and kinds named, but as
these differ from our English kinds it is unnecessary to
give the list. A summary of the above might be shortly
stated thus, beginning at harvest-time* : —

If possible reap so as to leave the "flax-seeds " in the
stubble, and destroy this infested stubble; otherwise
treat the harvested straw so as to destroy them.

If flies are likely to be about let the self-sown corn
on fields that were infested sprout, and presently turn
sheep on to feed off the infested plants, and then plough
the remains in. Ploughing in infested stubble is also
useful. " Bait " may also be had recourse to by sowing
strips or patches of corn to attract the fly, and treating
them as above.

Late sowing, so that the young wheat will not be up
until the autumn brood is dead, is a most important pre-
caution, but, as it appears to be safe if put in after the
beginning of October, this point is usually met in this
country without special arrangements.

Dressings, and mechanical measures, as rolling, &c.,
may or may not answer, according to circumstances.

* In American treatment the great importance of preserving the insect
parasites, which feed on the Hessian Fly in its early stages, is most
urgently insisted on, as in that country they are as much looked to for
keeping down the attack as Ladybirds are in our own as a check on Hop
Aphis. Consequently burning stubbles, or burying them deeply, or other
treatment which would kill parasites as well as pests, is thought doubt-
fully of. In the foregoing notes I have not entered on this consideration,
because as yet we do not know that the parasite insects have followed in
the train of the fly.

( 23 )

All measures to secure good hearty growth, such as
may carry the moderately injured plants through attack,
are very desirable.

So is rotation of crop, as the fly only attacks certain
cereals specified.

Strong- stemmed corn is less liable to attack than
kinds of which the outside is more readily injured by
the maggots.

The above methods of treatment mitigate the violence
of the attack, and if in the coming season we find this
injury, which has now for over a hundred years caused
from time to time such devastating loss in America, has
settled down here, we cannot do better than study in full
detail the reports of observation and agricultural treat-
ment which have been found to mitigate the evil.

But meanwhile it is most urgently to be considered,
WHEEE DID THE ATTACK COME FROM ? As in the hundred
years and more that it has been in America, and about
half that time that it has been known in Europe, we
have no records of its presence as a crop-pest ; and
plenty of records of it not being present it is reasonable
to suppose that there has been some special circumstance
which has not occurred before to which we owe its
presence. To find what this is would be to find how to
free ourselves from a most dangerous crop-pest, and if
all concerned would examine into the various ways in
which it can have been conveyed on the land, and will
continue this watch and report on it in the coming
season, we may hope to learn the source of the evil.

I will venture to add that I shall have pleasure in
receiving any communication on the subject, or samples
of infested grain, and also samples of winter wheat or
barley considered to be infested, and in giving all infor-
mation that lies in my power on the subject.

ELEANOE A. OEMEEOD, F. E. Met. Soc.,

Consulting Entomologist of the Royal Agr. Soc. of England.

DUNSTEE LODGE, NEAR ISLEWORTH.

( 24 )
BIBLIOGRAPHICAL EEFEEENCES.

The following list gives the titles of some of the publi-
cations in which information will be found regarding
the original identification of the species of Cecidomyia
destructor by Thomas Say, and likewise regarding its
habits, history, and distribution in America and Europe,
and means of prevention and remedy. The most im-
portant and serviceable of the papers are those of the
U.S.A. Department of Agriculture, and the papers by
Dr. B. Wagner :—

Some account of the insect known as the Hessian Fly. By
Thomas Say. Journal of Academy of Nat. Sciences, i., pp. 45 - 48,
1817.

The Hessian Fly ; its ravages, &c. U. S. A. Department of Agri-
culture : Third Eeport of Entomological Commission. Washington,
1883. (Eeprinted, with additions and corrections, from Bulletin IV.
of the U.S. Entomological Commission. By A. S. Packard, jun.,
1880).

The Hessian Fly : its history, &c. By Asa Fitch, M.D. Trans,
of the New York State Ag. Soc., vi., 1846. Albany, 1847.

The Hessian Fly not imported from Europe. By Dr. H. A
Hagen. Canadian Entomologist, 197 - 207, 1880.

Introduction to Entomology. By W. Kirby and W. Spence.
1815-26, i.

Untersuchungen iiber die neue getreide gall-mucke. Von Dr.
Balthasur Wagner. Fulda & Hersfeld. 1861.

Die neue kornmade. Von Dr. H. Loew. 1859.

Naturgeschichte der schadlichen insecten. Von V. Kollar. Wien,
1837. English translation by J. & M. Loudon, with notes by J. 0.
Westwood. London, 1840.

Untersuchungen iiber Insectenschaden auf den schlesischen
getreidefeldern im Sommer 1869. Von Prof. Dr. Ferd. Colin.

Die schadlichen insekten Kusslands. Von. F. T. Koppen. St.
Petersburg, 1880.

Synopsis Cecidomyidarum. Von J. E. Bergenstamm und Paul
Loew. Wien, 1876.

Die Praktische Insekten kunde. Von Dr. E. L. Taschenberg.
Bremen, 1880. Pt. iv., pp. 9 - 14.

Die Pflanzenfeinde aus der classe der Insekten. Von J. H.
Kaltenbach. Stuttgart, 1874. Pp. 734-741.

PBINTED BY WEST, NEWMAN AND CO. HATTON GARDEN LONDON, E.G.

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