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Psyche 4:23-26, 1883.

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PSYCHE.
THE SCALES OF COLEOPTERA.
BY GEORGE DIMMOCK, CAMBRIDGE, MASS.
(Continued from 'page 11.)
SCALES OF HOPLIA.
A few only of the scales from the
upper side of this insect are colorless, and, as these seem to be undeveloped
or immature, I tried no experiments
upon them.
The scales of the under side of H.
coeniica are purple, purplish red, red,
bluish and colorless by transmitted light, and by reflected light they are silvery
white with a tendency to metallic green
in places. The scales of the tip of the
abdomen, altho really dorsil in position, are covered with spines, are mostly
reddish or purple by transmitted light,
and are metallic green by reflected
light. Some of the scales of the legs
are like those from the rest of the under surface of the insect; others of them
are lanceolate (fig. 3, c), and colorless or milk-white, but covered with longer
spines or hairs than the more circular
forms of scales. The hairs of this in-
sect have fine branches, as do the hahs
of all sc~rabaeidae, according to Fischer and according to my own observations.
Water, alcohol, chloroform and simi-
lar reagents render the scales of the
under side colorless and transparent,
the colors returning as soon as the
scales are dried.
In finer structure the scales of the
under side are different from those of
the upper side in being clothed with the before-mentioned spines or fine hairs,
and in the absence of the, fine internal network, which is here replaced in some
scales by a more irregular internal
rnarking of like nature.
The scales of Hoflia modesta, from
this country, are confined to the tip of the abdomen and to the under side
of the insect. They are all gray or
milk-white by transmitted light, and
silvery by reflected light. They are
narrower than those from corresponding
parts of H. coerulea, but are otherwise
alike in structure and need no further
mention here.
SCALES OF POLYPHYLLA.
The whitish spots upon the elytra of
PolyfhyZla variolosa are produced by
lanceolate scales, the opake whiteness
of which is caused by the large amount
of air contained in them. As they pre-
sent no characters of special interest not to be found in scales of other coltoptera described in this paper I have not drawn them or further studied them.
Pu&f 4 023-27 (pre. 1903). hfp //psyche aitclub orgM4-0023 htd



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24 x's2Tf?Y2?. [March-April 1883.
SCALES OF VALGUS SQUAMIGER.
Nearly every part of V. squamiger is
covered with scales which are of two
colors, an opake dark brown and a semi-
opake white. The scales are somewhat
rolled and are very brittle, so that when they are pressed beneath a cover-glass
upon the microscope slide they usually
split at the edges. The unbroken scales
are nearly round, about 0.14 mm. long
by 0.08 to o. I 2 mm. wide. and until they are deprived of air but little structure is visible. When they are deprived of air
they are seen to be covered with dense,
rather long hairs, -to be in fact almost Fig. 4. Scale of Valgus sq?~amiger. Enlarged loo diam.
shaggy.
Fig. 4 represents an unbroken
scale that has been treated with alcohol to remove the air.
The hairs, as will
be seen by the figure, are arranged,
somewhat roughly, in transverse or 011-
lique lines ; but what is more curious,
the basal ends of these hairs seem to be connected, in each line, with one anoth- er, and finally each of these bands of
hairs, which may contain from two to
twenty hairs, seems to connect by its
basal line with a branch going to the
basal end, or stem, of the scale. These
branches unite as they approach the
basal end of the scale until they form
one trunk. These ramifications are del-
icate brown and are beautiful on a prep- aration of the scales in Canada balsam.
In fig. 4, which was made too small to
show them correctly, they are propor-
tionally far too coarse, and are not tap- ered as regularly as they should be from base to tip.
I have not found this ramified structure in any scales except those of Valgus,
and in them I have not studied it to any extent. It appears as if the cavity of
the scale, once open and probably open-
ing into the large hairs, had closed grad- ually, leaving channel-like folds between the hairs and from them to the stem of
the scale.
These channels are appar-
ently entirely closed now, altho I made
no sections of these scales to absolutely prove this point.
HAIRS OF PSILOPTERA.
The under side of the abdomen and
other parts of Ps. drummod are clothed
with brownish-yellow hairs, which are
set upon a smooth, nearly black surface, and consequently the hairs appear of a
light bronze color. -
Fig. 5. Hair of Psjloptera drummondi. Enlarged loo diam.
Seen under the microscope these hairs
or scales-for they seem to be as much




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March-April 1883.1 PSTCXLE?. 25
scales as they are hairs-are sword-
shaped (see fig. s), and of a yellowish
color. Their length is from 0.25 mm.
to 0.30 mm.,, their width about 0.01
mm., and they are covered with longi-
tudinal striae, which are usually about
0.001 mm. apart. These hairs or scales
are easily seen to contain air by using
water or alcohol to drive it out. I in-
troduce them here only to illustrate this somewhat common form of appendage
intermediate between scales and hairs.
I have found no other sq~~amiform ap-
pendages on the limited number of
bu$restidae which I have examined.
No description has been given, as far
as I can discover, of scales in elater-
idae, altho the generic names Chalco-
lepis and Chalcole$idius7 and the spe-
cific names of Adelocem Ze$ido$tem
Lacon leprosus, A4e?-is/hus lepido-
Monocre/idius Zepidus, Cryptohypnus
squamzyeq and others, would imply that
the presence of scales had been either
suspected or verified. That the scales
of elateridae are interesting in form
and structure can be seen by the follow- ing descriptions of scales of Chalcole$- idius, of Alaus and of an undetermined
species of European elateridae.
SCALES OF CHALCOLEPIDIUS.
Nearly the whole surface of C. rubri-
tennis, except its elytra, is thickly cov- ered with scales, which give to the parts thus covered a peculiar metallic or
bronzed aspect, with colors changing
from blue to greenish or reddish.
The scales from all parts of this insect are very much alike, varying little in
form (see fig. 6, a, 6, and c). They
are all of ovate form, more or less elon- gate, with the larger end toward their
shank or stem, which is nearly always
broken off in removing them from the
insect ; they are very flat. scarcely con- vex above, but do not rest very tightly
pressed upon the surface of the insect.
Their length is from 0.09 to 0.15 mm.,
their width from 0.02 to 0.04 mm., and
their thickness is about 0.0025 mm.
These scales when removed and ex-
amined under the microscope are uni-
formly brown, except with very oblique-
ly transmitted light, when they are
sometimes purplish. If, however, they
are put upon a black surface and illuini- Fig. 6. Different forms of scales from CkaZcoZepidizs rutripennis. Enlarged 100 diameters.
nated from above they are brilliant with blue, red and green, the color depending upon the position of the surface of the
scale with reference to the light. Put in direct sunlight, on a black surface, and the microscope focussed somewhat above
them, the light is decomposed in fine lines of brilliant blue, green and red. as if
series of solar spectra were drawn up
near each other, thus indicating striation of the scale-surface. The scales have a
very slight tendency to longitudinal fold- ing, but no striae, or really distinct




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26 7's 2%'h?A!?. f ~Marcb-April iSSj.
folds, are visible upon them. The
shank and a little of the basal portion of the scales are hollow ; whether the whole scale is hollow I have not determined.
Treatment with water, alcohol, glyc-
erin or turpentin does not seem to affect the scales of Chalcole$idius, which ap-
pear to contain no air. They are not
bleached by chlorin bleaching reagents.
SCALES OF ALAUS.
The two velvety black spots upon the
dorsal surface of the thorax of A. ocula- tus. to which this insect owes its specific name, are formed of scales, as are also
all the white portions of the beetle, the ground color of the whole insect being
a slightly shining black. Tile same re-
marks apply to A. myo$s, the scales of
which are like those of A. oczdatzts in
every respect.
Fig. 7.
Scales of AZaz~s oczilafus; (1, brown scale ; b and c, portions of white scales to show cross-bands; d, transverse section of a brown scale. Enlargement : a, loo diain. ; b and c, 300 diam. ; d, 500 diam. The form of all the scales of A. ocu-
Zatus is scaphoid, with the concave side toward the insect. The scales are stri-
ate on the convex side, but smooth on
the concave side,
Fig. 7, a, illustrates
their form, the lower end being the one
attached to the insect. In some cases
the shank by which the scale is attached is proportionally longer than is shown
in the figus-e. These scales are inserted by their shanks in holes irregularly dis- tributed in the chitinous covering of the insect. The irregular arrangement, pe-
culiar form and striation, and mode of
insertion of the scales of A. oculatus
forcibly remind one of the leaves in :i
bed of lily-of-the-valley ( Convai'Zaria') when these leaves are blown toward one
direction by a gentle breeze.
The scales of A. oculutus are all of
about the same size-about 0.20 to 0.23
1111n. long by 0.04 to 0.05 mm. wide, and 0.095 mm. in greatest thickness-from
whatever part of the insect they are
taken. Those which form the two
black thoracic spots are deep brown
when seen under the microscope, and
the others are opake white when dry.
The striae of these scales are about
0.002-5 mm. apart, and converge some-
what toward each end of the scales.
The striae of the white scales are a lit- tle less distinct than are those of the
dark scales, the whole white scale, to
appearance, when viewed with a low-
power microscope, being covered with
minute cross-lines, so numerous as to
give the scale an opake white color.
Under higher magnifying power these
transverse lines present an appearance
as in fig. 7, b and c. The longitudinal
striae are above the transverse lines, i.e., on the convex side of the scales, while
the cross-lines extend as interrupted,
transverse bands across the lower or
concave part of the scales. No trans-
verse bands are visible, even after, re-



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March-April 1883.1 P.!?TCH.l?. 27
moving the air, in the brown scales. In
gitudinal striae toward the middle of the the white scales the bands usually start scale (see fig. 7, b and c) ; exception- out from or beneath the marginal longi-
ally, however, they begin beneath one
tudinal stria of the upper side of the
of the other longitudinal striae.
scale, and extend beneath the other lon- (To be continued.)
PIOMINIVOROUS HABITS OF LUCILIA MACELLARIA, " THE SCREW-WORM."
BY FRANCIS HUNTINGTON SNOW, LAWRENCE, KANSAS. I have from time to time had occa-
sion to note the depredations of the
screw-worm upon horses and cattle in
this 'state, but until recently have not received positive evidence of its attacks upon human subjects in any locality so
far north as Kansas. But early in Sep-
tember, 1882, I received from Mr. S.
D. Osborn, the postmaster at Varck,
in Southeastern Kansas, specimens ('of
the worms which came from the nos-
trils of Milton Carter." These proved
to be the larvae of Lucilia maceZZaria
Fab., the so-called (' screw-worm."
Upon further inquiry I learned that
upwards of one hundred full-grown
maggots escaped from the nose of this
patient, who finally recovered from the
serious illness consequent upon their
ravages. I also ascertained that Mr.
Carter had long been afflicted with an
offensive nasal catarrh, which made
his nostrils an attractive place for the oviposition of the fly, and that he had
fallen asleep in the woods in the day-
time only a few days before the first
appearance of the symptoms produced
by the presence of the larvae.
Several other instances of the attacks
of Lucilia upon man soon came to
my knowledge, most of which led
to fatal results. Among these I will
select the case attended by Dr. J. B.
Britton, of Mapleton, in southeastern
Kansas, who reported it in full at the
session of the Southeast Kansas District Medical Society, in January, 1883.
From this report I condense the follow-
ing account : " On the evening of Au-
gust 22d, 1882, Mr. M. E. Hudson
complained of a peculiar sensation at
the base of the nose and along the
orbital processes, which was first fol-
lowed by inordinate sneezing, and later
by a most excruciating pain over the
os frontis, also involving the left supe- rior maxillary. This patient also had
suffered, and was still suffering, from
an aggravated form of nasal catarrh.
The discharge was quite purulent, of
a yellowish color frequently tinged with blood, with a disagreeable odor and
at times intolerably offensive. On the
24th there was a profuse discharge of
much purulent matter from the nostril
and mouth, when all pain instantly




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