Article beginning on page 327.
Psyche 8:327-329, 1897.

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PSYCHE.
THE MOUTHPARTS OF THE NEMATOCEROUS DIPTERA, 11. BY VERNON La KELLOGG, STANFORD UNIVERSITY, CALIFORNIA. In the following account of the presented by any other of the mandible- mouthparts of the Nernatocera, that
possessing ~ematoceious females.
nomenclature of parts is used which
represents the interpretation of the
mouthpart homologies most widely
accepted at the present time. As some
nomenclature is necessary and the
author's interpretation of the homol-
ogies may not, consistently with the
point of view adopted in this study, be
set out until the testimony of the study has been presented, the nonkenclature
of common acceptation is naturally
used. As the mouthparts of one repre-
sentative, at least, of each family, are figured from drawings made by camera
lucida, the descriptions of the various
parts are made very brief. Owing to
the limitations of space, in most
instances the mouthparts are figured in
situ alone ; in some instances, however, figures of two or three of the isolated
parts are given. As all the Neina-
tocerous mouthparts are alike in essen-
tial character and arrangement, the
figures of the cross sections of the
mouthparts of Bkfhamcera capitata
illustrate nearly as well the conditions Liponeura? sp. This species is a
large undescribed Blepharocerid, taken
by me in California, and should proba-
bly be made the type of a new genus.
The mouthparts of the female consist of
the following well developed, indcpend-
ent and easily distinguishable parts
shown in figure I in sit?( to reveal the relative size and natural position with. regard to each other: a labrum-epi-
pharynx (l. @), a pair of mandibles
(mi), a pair of maxillae (mx), a labium
(Zi) and a hypopharynx (hyf).
The labm?t;-epipharynx (fig. i A, 1.
e$\ is elongate, slender, and pointed,
and bears numerous taste pits (?) on its lower (inner) surface which is concave.
The mandibles (fig. i A, md) are long,
slender, well chitinized, and each is
sharply, finely and conspicuously serrate along the distal half of the inner mar-
gin. The mandibles are articulated
wiA the head capsule wholly distinctly
from the other mouthparts.




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328 PSYCHE. [March, 1899.
The maxillae (fig. I A, mx) consist have no pseudo-tracheae. There are of a single short, tapering, blade-like, no palpi. thin but well chitinized maxillar lobe The hypopharynx (fig. I A, hyp) is as (mx. I) and a long, slender, 5-segmented long as or slightly longer than the la- palpus (mx). Lobe and palpus arise brum-epipharynx, is narrower, and from a basal sclerite, which shows no although thin, well-chitinized. It lies differentiation into cardo and stipes, along the dorsal surface of the labium and may be taken to represent these underneath the labrum-epipharynx. two sclerites completely fused. As shown in figure I A, the mouth- The labimn (fig. I A, If) consists of parts, excepting the mandibles, are car- a strong elongate basal sclerite which ried somewhat forward by the extension presents indications of aline of fusion
of their bases or of the frontal part of of sub-mentum and men tun^, and a pair
the head-capsule. The various parts of
the mouth dissect apart readily.
E Riefharocera capitafa. The mouth-
\ a Dh" parts of the female resemble the Q
mouthparts of the previously de-
scribed member of the family with,
however, certain interesting differ-
ences in the labium. The basal
sclerite of the labium terminates
a,), p a
proximally in a strongly chitinized
v"y sub-crescentic portion, much like
the sub-mentum of certain orthop-
terous forms. There are three in-
dependent (at least, distally) ter-
Fig. I, A, Mouthparts of Lz'fonewu ? so., minal lobes instead of two, the outer
9; I. e.f lahrum-epipharyn, md mandible, two of which may be taken to be the
mx. maxillae, mx. I maxillar lobe, WZÌö / paraglossae, and the inner median one
maxillar palpus, /i labium, 9;'' paraglossa, the fused glossae or inner lobes. Series hyp hypopharynx; B, Cross section near the base of the mouthparts of BZe@amem caf-
of cross sections of the mouthparts in
itafa 7; C, Cross section near the tip of situ show well the general relation of
mouthparts of Bie/hurocera cafitata $ ; the parts (fig. I B and C), and show . -
lettering in B and C same as in A, with
tiat the terminal lobes of the labium are addition in C of gZ glossa, and substitution distinct distally, and that the hypo-
of Ib for /. ep (.Ì labrum-epipharynx).
pharynx is traversed from base to tip by - . -.
of free fleshy terminal lobes, the para- a cylindrical channel. This is of course
glossae (pg) (see account of Blepha-
the efferent duct of the salivary glands. rocera cafitata), These terminal lobes The sections show plainly the origin



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March, 1899 I PSYCHE. 329
of the hypopharynx from the dorsal
surface of the labium (floor of the
mouth).
In the male* the mandibles are
wanting, the other mouthparts being as
in the female.
I have examined the mouthparts of
pupae, male and female, ol various ages, and find some interesting conditions,
but this is ontogenetic study, and we
shall for consistency's sake present now only the results of the study of the com- parative anatomy of the adults.
Simulium sp. In the females of
Simulium sp. the moutl~parts (fig. 2)
are of the type presented by Blepha-
~occru but present some interesting
modifications. The mouthparts are
short and broad in general character,
instead of elongate. The lab-efi-
fihurynx (fig. 2 Z. ('/I is broadly and
bluntly triangular and can be readily
separated into two lamellae, a dorsal and a ventral one, obviously labrum (fig. 2
Zb) and epiphai-ynx (fig. 2 ef) respec-
tively. Tlie epipl~arnyx presents, at its distal extremity, four minute strongly
chitinized processes, evidently mere spc- cia1 chitinizations of the epipharyiigeal cuticula. The mandibles (fig. 2 mil) arc short, broad (as compared with Die
mandibles of the Blepl~aroceridae) ,
thin and weakly chitinized. They have
a well-defined articulating condyle at
~-
I n the Zoologisclier Anzeiger no. 557, p.a8o,'iSg8, I lime aid iinstakeuly that the mandibles are present in the male. base. The maxillae (fig. 2 mx) consist
of a basal sclerite, a long 5-segmented
Fig. 2, Moulhparts of Siimdium sp., $2;
Z. e-p labrum-epipharynx, md
mandible, ma
maxilla, m'v. I maxillar lobe, 9nx.p maxillar palpus, Zi ldbiuin, $g paraglossa, g glossa, hyp l~~popharynx, Ib labrum, ep epiphar- vnx.
palpus and a single maxillar lobe reach- ing nearly to the end of the third palpar segment.
This is serrate on its inner
margin at the tip, and is better devel-
oped than in most of the Nematocera.
Thc labium (fig. 2, A') is short, broad, with a short basal sclerite and three
terminal lobes, two large free paraglos- sae, and a median short membranous
lobe, the fused glossae. The terminal
lobes present no sign of pseudo-tra-
cheae. There are no palpi. The
hypopharynx (fig. 2, Ayp) is about as
long as the labrum-epipharynx but
narrower and its narrowly pointed apex
is finely serrate on both margins.
Simulium sp. A second species of




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330 PSYcxWZ. [March 1899.
Simitlivm examined presented no differ-
are free and independent to their bases. ences in mouthparts structure.
The hyfopharynx (fig. 3, hyp) is a little Ceratofqon sp. The mouthparts of
females present, as ;>hewn in figure 3,
parts similar to those described for the Blepharoceridae and the Simuliidae.
The well-chitinized lal'rm epipharynx
(fig. 3, lh) is elongate, broad at base
and tapering to a blunt tip which bears
two minute processes of the character
of those. of the Simuliid epipharynx.
The mandibles (fig. 3 2nd) articulating
on either side of the labrum-epiphai-ynx are, with it, borne by a portion o[ the
head capsule produced anteriorly so
that the bases of labrum and mandibles
lie considerably in front of the bases of maxillae and labium. Each mandible
articulates with a slight projecting
process of the head capsule. The
mandibles are strongly chitinized, elon- gate, narrew with convex outer margin,
and with a few strong, sharp teeth (den- tations) on the apical inner margin.
The maxillae (fig. 3 mx) consist 01
slender 5-segmented palpus (mx.p) and
single blade-like maxillar lobe (mx. 1}
reaching to end of second palpar seg-
ment. The labizmi (fig. 3 K) bears but
two terminal lobes, the paraglossae, and these appear to be 2-segmented. They
Fig. 3, Mouthparts of Ceruto'pogon sp., 9 ; lb labrum-epipharynx, md mandible, mx
maxill~~ mx. I maxillar lobe, mx. å´ maxillar palpus, li labium, $8 paraglossa, Jiyp hypo- pharynx.
broader than the labrum-epipharynx, is
weakly chitinized, and is weakly but
conspicuously serrate at its apex.
The males of Ceratoposon have no
mandibles, and the maxillae have no
terminal lobe, and only 4-segmented
palpi.
Chironoinus sp.
In females of Chiyo-
noms we meet a mouth structure differ-
ing essentially from that of females of
Ceratupopn in that there is lacking in
Chirunomus the. mandibles and the
naxillar lobes. The mouthparts of
Chiroizumus are also short and broad
and not elongate as in Ceratopogun.
Chi~onom~~s does not possess, as Cera-
tupogon. does, piercing mouthparts.
EXCHANGE DESIRED.-Dr. A. Griffin; of
Dytiscus, pinned or in alcohol, in exchange the University of Turin, Italy, desires to for Italian insects of any order. Address as obtain American specimens of Cybister and above.



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