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Psyche 5:222-227, 1888.

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NOTES ON THE EPIPHARYNX, AND THE EPIPHARYNGEAL ORGANS OF TASTE IN MANDIBULATE INSECTS.
BY ALPHEUS SPRING PACKARD, PROVIDENCE, R. I. (Concluded from p. 199.)
Order Platyptera.
Pteronarys feu.-In a specimen
from Pagosa, San Juan River, Colora-
do, the surface of the labrum is pro-
vided with stout curved setae which are
often forked at the end, like those occur- ring on the joints of the antennae and
caudal stylets. The epipharynx is
densely pilose on the edge and over the
surface, but there are no sense-cups or
rods.
Perla sp.-In a specimen from the
Glen, N. H., the labrum is broad and
very short, full and rounded, and there
is no trace of a median furrow. The
epipharynx has a narrow, curved, long,
transverse area parallel to and situated near the front edge, on which are
two opposing sets of broad-based
"gathering" or "hooked" hairs ; else-
where the surface is covered with fine
tactile setae, which arise from a cup-
shaped base. There is a median furrow
free from these setae, and I cannot detect any genuine taste-cups.
In another species from Montana
there is the same structure of the
epipharynx, which bears at the end a
number of tactile setae arising from a
cup-shaped base, but there are no true
taste-cups.
Psocus novae-scotiae Walk. - La-
brum rather large and broad, and some-
what excavated on the front edge. The
epipharynx in front is divided into lobes, the front edge of the middle one of which extends a little farther out than the
lateral lobes, and has a straight edge.
This lobe bears two rows of short setae, those of the distal or marginal row being shorter and consisting of five or six
stouter setae, which are blunt at the tip and have the appearance of having been
worn off. On the basal half in the
middle is a large polygonal pilose area. I cannot detect any sense-cups.
Psocus sp.-In a species from Florida
the labrum and epipharynx, with the ar-
mature of the latter, are as in the preced- ing species, and there are no sense-cups to be seen. They seem to be wanting
in this genus.
Eutermes riffed.- In a larval and
a winged female from Nassau the la-
brum and epipharynx have the same
shape and armature. The end of the
labrum is full and round, with no trace
of a median suture. The epipharynx is
pilose, with a few long tactile setae.
On the front edge is a transverse row of six gustatory ( ?) setae, each bristle being acute and arising from a beaker-like
base. Along each side of the median
line on the anterior half of the epi-
pharynx is a group of about 20 scattered



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peculiar long depressed tubules ending
in a circular membrane, out of which a
very short hair projects.
These appear
to be gustatory.
There are also two
curved rows of minute cells with a
nucleus, three deep, which extend on
each side from under the front edge of
the clypeus and end near the front edge
of the labrum, the two rows converging
in front; they are very singular in
shape, and towards the front the cells
become much elongated and arranged
in four or five close ranks.
These are
probably not sensory cups, but modified
surface setae.
Termopsis angus/icollis Hagen .-In
a female from the Pacific Coast I cannot detect any taste-cups and any organs
that appear to be gustatory. The sur-
face of the epipharynx is simply pilose. Order Odonata.
Calofteryx sp.- In a specimen from
Florida the armature of the epipharynx
is much as in Diplax, and there are 25
taste-cups on each side of the median
line, but extending farther in front than in Diplax.
D+ax sp. - In this as the other
dragon flies examined, the labrum is
full on the front edge, but there is a fine median suture extending back nearly
half way to the base meeting a wide
triangular or V-shaped gap. On the
anterior edge of the epipharynx is a row of long stiff tactile setae ; there is a lat- eral group of tactile bristles pointing
inwards and another smaller group of
similar setae
in the middle on each side
of the median suture, while a few
minute hairs extend to the suture.
There is a group of about 14 taste-
cups at the base of the labrum on each
side of the median line ; the central
bristle cannot be seen, but as the nucleus is well defined when looked at vertically there is probably one present in each
taste-cup. On the outside of each gus-
tatory field are a few inwardly-directed defensive setae. Also outside of each
group of taste-cups are near the base of the labrum a group of singular parallel
sabre-shaped setae, pointing inwardly
and likewise directed towards the base
of the labrum.
Aeschna heros Fabr.- Epipharnyx
armed with small, short, slender bristles, which along the base (z'.e., under the
base of the labrum) on each side of the
median line become very stout and
short. In front of this group of -short
setae is a pair of short-handled brushes consisting of stiff, coarse setae, one on each side of the median line. In the
middle, but situated rather far apart, are two roundish pilose areas. There are
two groups of about 25 to 30 taste-cups, like those of Calo-pteryx and Di'Zax,
being without a distinct hair and sit-
uated as in those genera.
Order Nezm@tera.
Stalls infumata Newm.-Along the
median line of the epipharynx and near
the front are about twenty scattered
gustatory pegs, which are minute, but
longer and more acute than usual. The
other setae are large, long and scattered over both sides of the organ.




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Chauliodes maculatus Ramb.- The
entire surface of the epipharynx is cov- ered with very fine hairs which are
broad at the base and very short.
There are one or two taste-cups under
the front edge of the clypeus ; others are scattered along the middle from the base of the labrum to the front, but are not
arranged in definite order.
Corydalis codus Linn. - The
epipharynx of the female is covered with scattered tactile setae, and there are no sense-cups, pits, or rods to be seen.
Chryso$a sp.-In a specimen from
Florida the labrum is deeply notched at
the end. Over the epipharynx are scat-
tered cups with a short acute bristle,
which are probably gustatory in function, though they are not confined to the
median region of the epipharynx.
Myrmeleon diversum Hagen. -Lab-
rum very short, with a slight shallow
median excavation. As in Chvsoi)a,
the presence in the epipharynx of sense- pits or taste-cups is doubtful. What
at first seem scattered taste-cups, mostly bear long tactile hairs, which in some
cases are very fine and short.
But there
is a group of pits, probably gustatory,
about twelve on each side of the anterior clypeal region, from one to three of
them being situated on the base of the
labral region ; there are also a few on
each side near the base of the labral
region, some of those in the triangular
area near the front edge of the epi-
pharynx may also be gustatory in func-
tion. On the whole I am disposed to
regard these structures as taste-cups.
Mantisto, brumzea Sav.-In a sneci-
men from Utah the labrum is rather
long and pointed in front, with no
traces of a median suture. On the side
of the epipharynx are tactile hairs, but along the middle from the base to near
the front edge are scattered about 30
unmistakable taste-cups, each bearing a
short, fine hair. This confirms me in
the belief that the structures above de- scribed in Ckysopa and in Myrmeleon
are also gustatory.
Order Coleoptera.
I have been unable to detect any
sense-organs in the epipharynx of Den-
droctonus rufipennis Kirby, or of
Lucanus duma Thunb ; on the other
hand, taste-cups occur in the larva
of cerambycid, scarabaeid and other
beetles ; but I have been unable to dis- cover any taste-organs in the larva of a rather large elaterid from Florida.
Moreover, taste-cups appear to be about
as well developed in the carnivorous
beetles Carabidae as in the phyto-
phagous or lignivorous groups.
Eficauta macuZata Say. - Labrum
hollowed in front. Epipharynx with
unusually numerous taste-cups, which
are conical papilliform, and truncated
at the end as if open, the edge of the
opening is ragged, but no distinct bristle is present, except in a few. Over 100
taste-cups were counted in the middle
and near the front ; around the edge of
the sinus is a regular marginal row of
large, longer, more distinctly chitinized taste-cups, whose walls are streaked up
and down by chitinous thickenings.
L a It will be seen that in number, structure



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and arrangement these organs present
excellent and distinctive specific char- acters.
JEpicaufa callosa Lec. - In a speci-
men from Montana, the labrum is
notched and on the epipharynx over the
region around the bottom of the notch,
and fromthese to the base of the labrum
are scattered about 55 taste-cups ; and
also on either side of a median setose
ridge which passes back under the
clypeal region are about 10 cells, which may be taste-cups.
Nemognatha
l d a Lec. - In a
female from Montana a large triangular
area extending to and widening out on
the front edge of the epipharynx con-
tains about So remarkably small taste-
cups, not more than * to + as large as
those on the maxillae of the same beetle. Unless these are gustatory it is difficult to account for their presence here and
it will be observed that the taste-cups in Eficauta are unusually abundant.
Eleodes obsoleta (Say). - In this
tenebrionid from Montana, the epi-
pharynx is provided with a group of
from 15 to 20 taste-cups on each side in the middle of a squarish area situated in front of the middle, and whose sides are densely setose.
Diabrotica vittata (Fabr.) .-In the
common striped squash beetle the lab-
rum is suddenly and deeply notched,
though there is no trace of a median
suture behind the notch. The epi-
pharynx has a singular armature. Just
within the bottom of the labral notch on the under side is a row of four, broad,
conical setae, whose tips just reach the bottom of the notch.
Along the front
edge on each side of the notch is a row
of most singular broad, flat, thin, leaf- like setae which are closely appressed
to the broad, naked, epipharyngeal
margin. The surface of the epipharynx
is pilose, but the median region is
naked, and on the anterior half bears
from I I to I 2 taste-cups, arranged each side of the median line in a rude Y.
On each
side at the base of the labial
region are two sensory fields, each bear- ing about 25 to 26 taste-cups. More
were seen under the clypeus.
Le-ptura canadensis Fabr. - Front
edge of the labrum and epipharynx
densely fringed with slender, curved,
truncated setae. I can see numerous
taste-cups under the base of the labrum, and what seems to be scattered taste-
cups in front, but the labrum is too
opaque for a clear view of them.
Euryjtera lateralis Oliv. - In a
specimen from Florida the epipharynx
is fringed with long, slender, truncate, slightly curved hairs projecting from the front edge. Taste-cups are abundant
along and near the middle of the ante-
rior half of the labral region.
Cyllene robiniae Forst. (or $ictus
Drury) . - Labrum slightly excavated.
Epipharynx with a dense row of long,
slender, blunt rods, filling the sinus and extending beyond the edge of the lab-
rum. An area on each side gives rise
to very long tactile hairs, between
which and the median field of taste-
cups is a pilose lateral area. The taste- cups are more numerous than usual,
extending in an unbroken sensory field




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from near the front margin of the clypeal region to near the front edge of the epi- pharynx. The cups vary much in size,
some being one-half as large as others ; and those on the sides of the sensory
field bear short, and a few others rather long bristles, showing that the taste-
cups are modified tactile bristles.
Lachnosterna fusca Frohl .-Labrum
deeply notched, the sides of the sinus
armed with large, blunt setae. Epi-
pharnyx bearing on each side, outside
of a spring area, a group of about 50
taste-cups, each bearing a long setae,
and passing externally into a few high,
rather slender papillae, without a seta. On the under side of the clypeus is a
median group of 10 taste-cups of singu-
lar form, the cups being large, with
broad bases which posteriorly bear
three spines, of which the median one
is the largest. Behind these organs, the membrane is covered with slender
"gathering" hairs, which differ from
any previously observed in having a
nucleus at the base.
In a specimen from Montana belong-
ing to an allied genus, there is a group of about 30 taste-cups, which occupy
the same relative position as in the pre- ceeding species.
In Lacanus duma, the entire surface
of the epipharynx is pilose, and there
are no taste-cups, or sensory organs of
any kind present.
Clerus nigrQes Say. - Labrum
deeply cleft, but with no trace of a
median suture. Surface of the epi-
pharynx not pilose, but with scattered
defence setae. Near the edpe of the
bottom of the sinus is a group of 4 or
5 taste-cups, situated on each side of the median line, each bearing a small,
acute bristle. Behind these, under the
clypeus are two groups of 10 taste-cups
each, situated some distance from the
median line.
Teleflhorus rotundico ZZis Say.-La ;
bruim notched. The epipharynx is quite
unlike that of other beetles described, ex- tending quite far in front of the labrum, forming a thin, pale, membranous, pilose edge, and not provided with taste-cups.
On each side behind under the clypeus,
is a sensory field with 26 taste-cups,
which are rather smaller than usual.
Over the labral surface are scattered a
few taste-cups (?), but they are small
and perhaps not gustatory.
Lucidota $unctata Lee.-In a Flori-
dan specimen the labrum is narrow,
rather long, slightly rounded in front,
with no traces of a median suture. Un-
der the clypeus is a group of 12 taste-
cups, and in the middle region of the
labrum situated in a field extending from near the base to near the front edge are about 40 taste-cups, which, however,
are not, as is usual, arranged on each
side of the median line. The whole
surface is pilose, and the taste-cups in- stead of being as usual, situated in a bare region, are scattered among the hairs
forming the pile.
Buprestis maculiventris Say. -
Epipharynx with a few scattered, pecu-
liar, large setae appressed to the surface, and among them are a few minute,
sharp, either curved or straight pegs or setae, which mav oossiblv be snstatorv.




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but no true taste-cups were observed..
Corynzbi/es hieroglyphicus (Say) .-
Labrum full, slightly notched in front
with apparently faint traces of a median suture. Epipharynx pilose, the hairs
longest on each side. A few small,
scattered taste-cups under the base of
the labrum and others scattered along
the middle towards the front edge. On
each side of the anterior clypeal region is a group of 5 taste-cups.
Cam$ylus denticornis Kirby .-Over
the pilose surface of the epipharynx are scattered what may be sensory pits, but
they are not situated in a bare area, but among the fine hairs, and these organs
may be simply tactile.
Staphylinus. violaceus.-In a speci-
men from Florida, the structure of the
labrum is most singular. It is cleft to
its base, being divided into two long
lobes, with large long setae, and the
deep sinus is filled with very long,
densely arranged setae. Epipharynx
pilose ; under the clypeus, on each side near the middle, is a bare rounded area
in which are situated 4-5 papilliform
taste-cups, and at the base behind them
is another linear group of about 7 slen- derer, somewhat curved taste-cups.
Dytiscus spa-In a 9 Floridan spec-
imen there are on the epipharynx under
the clypeus, about 25 taste-cups, which
are papilliform, being higher than usual ; and on each side under the base of the
labrum is a sensory field containing a
number of taste-cups.
Harpalus faunus Say.-Epipharynx
with a median triangular depression be-
ginning at the base and widening
towards and ending on the front edge ;
this trough is lined with a row of spines, which are shortest towards a point lying under the base of the labrum. Over
the bottom of the triangular depression
(as it appears under the microscope, but in reality the roof of the area) are scat- tered shorter spines, and since gangli-
onated nerves can be traced to each of
the spines along the front edge, they are evidently at least tactile setae, and not simply adapted for defence. At the
bottom of the furrow are four brushes of bristles, and the posterior surface is cov- ered with very fine, short, "gathering
hairs." The taste-cups are situated on a narrow linear
field, one on each side,
lying half-way between the middle and
outer edge of the epipharynx, beginning
under the middle of the clypeus and ex-
tending only to a point situated under
the base of the labrum. The taste-cups
themselves are in irregular rows, 50 in
all, and in addition there is an aggrega- tion of g or 10 cups at the anterior and inner end of the gustatory field. Like
the others, these aggregated cups bear
each a central, short, conical peg. A
bundle of thick nerves can be seen end-
ing each at the base of the cup.
Chlaenius tomentosus (Say) .-The
epipharynx bears at a point situated
under the base of the labrum midway