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No. 62.

1ited States Department of Agriculture,

BUREAU OF ENTOMOLOGY.

L. O. HOWARD, Entomologist.

THE CABBAGE HATR-WORM.

By F. H. CHITTENDEN,
In Charge of Breeding Experiments.

Not since the “ kissing-bug”’ craze which originated in Washington,
D. C., in June, 1899, and spread generally throughout the country, has
there been anything like such a furor as was created by the discovery of
the so-called “cabbage snake,’’ a species of hair-worm, in the heads
of cabbage in Tennessee, South Carolina, and Louisiana, in the fall of
1903. That year the cabbage-snake scare was practically confined
to Tennessee and neighboring States southward. The first specimen of
Mermis albicans Diesing (fig. 1), which is the cause of the trouble,! was
identified from McCays, Tenn. This creature and its still somewhat
mysterious occurrence in cabbage has become a matter of much per-
plexity and annoyance to many of our correspondents, to economic
entomologists, and to chemists and physicians of the States where the
Mermis most abounds. Many reports have been received from reliable
correspondents of rumors of persons being poisoned by eating cabbage
affected by this hair-worm. Some
of these were gleaned from the daily
press, and many clippings of the
“yellow journalism’ order were re-
ceived. Among them were alleged
reports from a physician who stated
that when cabbage affected by hair-
worms was eaten it produced instant
death, and from a“ State chemist”’
who made an examination of the

worm and reported that it contained
ae to kill eight per- Fie. 1.—Hair-worm (MWermis albicans)—natural

enough poison m (Merm
size (original).

sons.’”’ In Raleigh County, W. Va.,
the cabbage crop was reported a complete failure, and “‘there was
enough poison contained in one worm to poison 25 men.’’ It should
be unnecessary to add that none of these reports had any foundation in
fact. Nevertheless the known presence of the hair-worm in an affected
district seriously injured the demand for cabbage there, causing very
1So many inquiries in regard to the identity of the creature and its alleged
poisonous nature were received that a short account was furnished under the
title ‘‘ Hair Worms in Cabbage,’’ in Bul. 44, of this office, pp. 93-95; and similar
inquiries are being made to date of publication. During 1904, frequently five or
six communications were received daily,

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considerable loss to truckers and grocers. The exaggerated reports of
1903 were not seriously considered; and it was a matter of surprise
when they were reiterated the following year, and what was in reality
a hoax assumed most serious proportions, not alone because of wide-
spread alarm caused by erroneous reports of loss of life, but also
because of the very material loss to cabbage growers and others who
handled this commodity, and the decided extension of the area in which
the hair-worm was detected. Encouraged by erroneous reports, evi-
dently incited in many cases by unscrupulous persons, the scare soon
became widespread, causing general fear of poisoning from Virginia and
West Virginia southward through the same States as were affected in
1903, and into Florida, and in addition westward to Kentucky, Illinois,
Towa, Missouri, Oklahoma, and Colorado.

DESCRIPTIVE.

The cabbage hair-worm is aptly described as resembling a piece of
basting thread, of the thickness of a strand of corn silk, of a darning
needle, of a No. 36 or No. 40 thread, or like a horse hair; white in
color; found coiled, or coiling and uncoiling; stretched at length or
crawling in cabbage heads; its length varies from 2 to 9 inches, but
reports have been received of a creature found in the heads of cabbage
measuring 9 feet! The imagination of newspaper writers as to color
runs riot through “ green, white, light red, olive green, and yellow.”

As a matter of fact this hair-worm is filiform or thread-like, and when
it attracts attention on cabbage, measures generally from 4 to 8 inches.
One specimen, doubtfully of the same species, measured when uncoiled
22 inches or nearly 2 feet. The color is white or whitish, although it
sometimes has a pale brownish or greenish tinge.

THE SPECIES IDENTIFIED.

Many popular names have been bestowed upon this worm, including

‘ ‘ ‘ .
“cabbage snake,’”’ “‘snake,’’ “‘snake worm,’’ “‘serpent,’’ “‘reptile,”’
° 6c 5 °
occasionally © cabbage worm,’’ and seldom if

1)

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cabbage rattlesnake,
ever hair-worm. Most specimens submitted for identification have
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proved to be what is known as Mermis albicans Diesing.' This crea-

ture is neither an insect nor a snake, but one of the hair-worms of the
order Gordiacea. The principal species of this order belong to the gen-
era Gordius and Mermis, and were treated somewhat at length in 1877."

! The studies of Diesing, Siebold, Meissner, and others have led to the expressed
belief that JZ. albicans is merely the mature sexual form of aewminata, the lat-
ter name having priority.

2 First report of the U. S. Entomological Commission, published in 1877 (pp.
326-334). The hosts of hair-worms include many Orthoptera (grasshoppers or
locusts, crickets, and katydids). They are sometimes parasitic on beetles, more
particularly Carabidee or ground beetles, on bees and flies, on caterpillars of but-
terflies and moths, and even on snails,

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Mermis albicans was received during 1903 in a piece of apple, found
coiled near the seed. This species is known to be parasitic on the cod-
ling moth or “apple worm” (Carpocapsa pomonella Linn.), which
accounts for its presence in this instance (1. c., p. 327). It is: also
parasitic on certain common and destructive forms of grasshoppers,
Melanoplus spretus Thos. or rocky mountain locust, M. differentialis
Thos. or differential locust, Schistocerca americana Dru., and Dissos-
teiva carolina Linn.!

LOSSES OCCASIONED BY RUMORS OF THE POISONOUS NATURE OF THE
HATR-WORM.

The presence of this hair-worm in cabbage and the unfortunate noto-
riety which has been given it, including the circulation of the merest
rumors, mostly vague and uncertain, of so many persons being poisoned
by eating affected cabbage, has seriously injured the money value of
this vegetable very generally throughout the affected States. Although
the cabbage hair-worm is not in the slightest degree deleterious to
health, the credence given to the most absurd rumors which were cir-
culated has injured cabbage for consumption and hence for sale. In
parts of Illinois the fears of growers and purchasers were such that
farmers were letting their cabbage go to waste. At Quinter, Kans.,
quantities of cabbage shipped from Colorado were reported burned
because of the presence of the hair-worm. In Tennessee it was esti-
mated that in 1904 fully 85 per cent of the cabbage crop of the State
was lost—in fact, a sudden and complete suspension of the industry
was actually caused. Similar reports were received from various por-
tions of Missouri, lowa, West Virginia, and Virginia. “* In Cheatham,
Smith, Franklin, Coffee, Bedford, and other counties [in Missouri]
hundreds of barrels of sauerkraut were destroyed through fear that the
dreaded snake might be a part of the ingredients.’’ At Columbia, Mo.,
hundreds of dollars worth of cabbage were lost. Many gardeners claimed
that they could not sell a single head on account of the “snake seare.”’

ALLEGED SICKNESS AND DEATH CAUSED BY HAIR-WORMS.

The general impression in regard to the poisonous nature of the cab-
bage hair-worm has been mentioned, yet considerable differences of
opinion prevail. To repeat alleged deaths and poisoning in detail
might have the opposite effect from that for which this circular was
prepared. Stories were circulated of whole families being poisoned by
eating cabbage affected with the hair-worm, sometimes with the reser-
vation that no one knew personally of their truth, and that many

1 The classification and habits of Mermis have not been given much study, hence
some slight doubt exists as to the species of Mermis observed in the case of some
of the hosts cited, but if one species will affect both lepidopterous larve and
grasshoppers, this is evidence of its not being overparticular as to its host.

cases were traced to their source and found to be utterly without foun-
dation. From Tennessee came a report of the death in one town of a
man, woman, and six children. In portions of the same and in other
States, persons were stated to have been taken ill with pain and yomit-
ing after having eaten cabbage on which the worms were subsequently
found. Possibly the consumers had been seized with temporary hys-
teria, Imagining that they had unconsciously eaten many individuals,
hence the symptoms. Others were reported severely poisoned or dead.
In most cases exact localities were furnished, but names were wanting.
In some cases domestic animals were said to have been poisoned; in
others cabbage was fed to them without any ill results.

The death of a man and wife and their four children in an I[llinois
town after eating snake-worm infested cabbage was reported in several
newspapers and the family name mentioned:

The entire family of six ate the cabbage at supper and died during the night.
A cabbage in the garden was examined and found to contain worms the size of
a thread, 8 or 10 inches long and about the color of the cabbage. The cabbage
was cut up and fed to animals, and all died. Farmers are destroying all their
cabbage. Three persons in the neighborhood have recently died after eating
cabbage.

In response to inquiry from this office the postmaster of this town,
the name of which is omitted for obvious reasons, wrote December 17,
1904, that efforts were made to locate the origin of the account, but
without success.

LIFE HISTORY.

The hair-worms of the genus Mermis develop within the body of their
host and, according to various writers, when about full grown desert it
by rupturing the body wall. These individuals are undeveloped sexually,
and characterized by a mouth consisting of a minute aperture, and a
minute anal point which is generally curved. On issuing from the host
the worm bores into the earth and conceals itself. During this stage in
the soil no food is taken, though several months may elapse, the creature
hibernating and becoming sexually mature before copulation takes place
in the spring. The sexes unite in knots, and the female deposits
lin the ground. Here the young, which are thread-like
like their parents, hatch and burrow upward to the surface, and enter
as parasites the bodies of caterpillars and various soft insects, such as
are found under leaves and other débris near the ground.

numerous eggs

The habits of Mermis in Europe have given rise to the belief in a rain
of worms. Not infrequently in summer time, after a warm rain at night,
swarms of these hair-worms appear on the surface of the earth, whence
the supposition that they are rained down.

‘Tt might be added that hair-worms positively do not develop from horse hairs.

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OTHER WORMS, INSECTS, ETC., MISTAKEN FOR THE CABBAGE WORM.

Numbers of hair-worms other than Mermis albicans, the larve of sciarid
flies, and some species of myriopods, as also angleworms, have been
received as undoubted cabbage snakes or as suspects. In fact, gullible
people throughout the affected region have literally gone “* hunting for
trouble”? and have sent everything conceivable except the true cabbage
worms (caterpillars of moths and butterflies), which are altogether too
well known, as suspected “‘ cabbage snakes.’’ Some of these, all, with
the possible exception of the myriopods and sciarids, of accidental
occurrence on cabbage, will be mentioned.

Mermis spp.—Various species of Mermis, related to albicans but differing in
various particulars, have been received with the usual reports of poisonousness.
One species of hair-worm, resembling the ‘‘cabbage snake’’ and possibly the
same species, was received from St. Clara, W. Va., in March, 1905, which
measured nearly 2 feet in Jength (22 inches) when uncoiled.

Puragordius varius, a suspect, was not found-in cabbage but in water
out visible means of support,’’ in Virginia.

Geophilus spp.—Numbers of myriopods of the order Chilopoda, which includes
the centipedes and millipedes, were among this number, nearly all belonging to
the genus Geophilus. There appear to be no positive records of any forms of
these creatures found in the United States inflicting serious injury to man, but
certain tropical forms are decidedly venomous. ‘These creatures sometimes
attack man, if accidentally handled, but they are not known to occur in cab-
bage. The poisonous species are large and conspicuous, and therefore not liable
to be eaten with food. The species of this genus have carnivorous habits, and
there is a possibility that they may destroy some forms of cabbage worms and
hence may be beneficial.

Earthworms.—Specimens of earthworms, in bad condition so that identification
was impossible, were received from West Virginia and Ohio, where they were
mistaken for the cabbage hair-worm.

Sciarids.—The larve of sciarid flies were received in several instances from
August until October, 1904, chiefly from Tennessee, Virginia, and South Caro-
lina. A correspondent at Duffield, Va., pronounced these maggots poisonous,
and said that death had resulted from the use of cooked cabbage in which they
had been found. A correspondent at Yokum, Ky., made a similar report.

‘

‘with-

HAIR-WORMS POSITIVELY NOT POISONOUS.

In spite of repeated published and written statements that the so-
called cabbage snake is not poisonous, this fact has not been given very
general credence, hence the matter is still imperfectly understood by
many. As it isan established fact that none of the hair-worms possess
poisonous properties, it was not considered necessary to make any analy-
ses or experiments at this Department to demonstrate their nontoxic
quality. However, Dr. Louis Leroy, Nashville, Tenn., who corresponded
with this office on this topic during August and September, 1904, under-
took to demonstrate beyond peradventure of doubt that the hair-worm
could not possibly cause harm to persons eating it or cabbage on which
it had occurred, and, although he has already published on the subject

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it may be well, for the benefit of skeptics, to repeat in substance his
conclusions :

During September he wrote that he had carried on a thorough investigation
of the alleged poisonous nature of this hair-worm, and found absolutely nothing
toxie connected with it, either when eaten raw or when cooked or on cabbage
on which the creature had lived. Efforts to trace every reported case of poison-
ing in Tennessee resulted in ascertaining that they were all without foundation,
no authentic case could be cited, and finally, he says ‘‘I am at a loss to under-
stand how such reports could gain credence and ever be published for facts in
the daily press.’’ In order to determine whether or not the hair-worm had any
poisonous qualities he instituted a series of experiments, using rabbits, guinea-
pigs, cats, dogs, horses, and cows, finding that they could all eat the worms,
raw or cooked, with impunity. Extracts from the hair-worms prepared with
various solvents were also found to be entirely innocuous, administered inter-
nally (per orem) and injected hypodermically.

‘Believing that possibly these worms might cause decomposition or fermenta-
tion in the cabbage, with the production of poisonous substances, the result of
the decomposition,’’ he allowed. samples of cabbage, both raw and cooked, to
decompose with the worms, and then tested the decomposed material for poison-
ous properties as above, and in no case was any toxic substance obtained.
Chemical analyses of the worms and the products of decomposition mentioned
were made, and he was nnable to find any ptomaine or other isolatable substance
of a toxic nature.

As a result the conclusion was reached “that the cabbage snake is
entirely harmless, and that public rumors and superstitions are fallacies
without semblance of foundation.”’

WASHINGTON, D. C. Jssued May 17, 1905.

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