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57 Appendix.

the Veterinarians, radiating into the chin. It begins about the
middle of the cheek and is here, by a small, tendinous, lamelli-
form portion, closely connected with the perpendicular bundles
of the superficial layer, which at first are rather sharply distinguished
from the depressor, but on approaching the angle of the
mouth the lower ends of several of these bundles turn forwards
joining the longitudinal bundles of the depressor so closely that
they can by no means be separated from them in the region of
the lower lip.

The deep layer of the m. buccinatorius (PI. 16, fig. 4) forms
a not very broad band of longitudinal bundles which proceeds on
the mucous membrane of the cheek in the direction of the angle
of the mouth; numerous small gl. buccales are imbedded between
the bundles. The lower bundles insert themselves at
the angle of the mouth, where they partly thrust between the
bundles of the pars rimana. The upper ones proceed into the
upper lip forming here the pars supralabialis, at first behaving,
in the main, as in the Camel: the fascicles run obliquely forward
into the upper lip, turn round the angle, where the upper
lip and the gingiva meet, and are inserted into the intermaxillary
bone; but they form a much lower arc, the gingiva not extending
so far upwards as in the Camel. Further forwards in the upper
lip, the fascicles successively take a transverse direction, and
at the foremost end of the intermaxillary bone the pars supralabialis
presents a quite remarkable development. From the anterior
end of the intermaxillary bone a dense and thick mass of
fibres arise which radiate partially to the ventral, partially to the
mediad side of the nostril; they do not extend into the upper
lip. In a young male specimen this anterior portion of the pars
supralabialis was continued a little way forward, beyond the
intermaxillary bone, that is to say: a portion of the pars supralabialis
is here found, which does not take its origin from the
bone; in this portion the fascicles are seen going from the ventral
side of the nostril to the middle line, where, in a raphe-
like stripe, they cross those of the opposite side.

The m. nasalis (PI. 11, fig. 1) forms a rather considerable
muscular mass radiating upon the lateral surface of the face behind
the arched portion of the soft nose. The bundles arise from
the intermaxillary and maxillary bones, in rows. The undermost
row arises just above the gingiva in about the region from the
hindmost corner of the nostril to p2, while the following rows gradually
arise from the bones higher and higher up. The bundles
are of about equal length in each row, but increase somewhat
in length in the upper rows, so that there is produced a tolerably
regular, tiled arrangement (v. PI. 11, fig. 1). The undermost
rows are separated from one another by the tendinous branches
of the m. maxillo-labialis and the uppermost are traversed by
numerous rectus-bundles.

The m. mentalis is quite a powerful muscle arising from the
lower jaw. Its anterior end is almost below z3. The arrangement
of the bundles is, in the main, as in the m. nasalis; they arise
in rows, one below the other, and radiate down into the chin and
the under lip, where they thrust between the rimana-bundles.

5. M. lateralis nasi

consists of a couple of groups of rather scattered fascicles (v. PI.
11, fig. 1). There is a posterior group arising from the upper end
of the intermaxillary and the neighbouring part of the maxillary
bone, radiating with its bundles forwards, and upwards, and inserting
itself outside the mucous membrane of the nose. An upper
group arises from the upper margin of the nasal cartilage,
extending down upon the mucous membrane of the nose.

Further, we have found some fascicles intimately attached
to the cartilaginous nose.

Below and behind the nostril there is an irregular, anchor-
shaped cartilage. From the exterior, and interior face of this,
there arises a fiat border of fascicles radiating upwards, partly
to the skin, partly to the mucous membrane. Judging from the
direction of the bundles, it almost appears as though it was a
portion of the m. rectus nasi.

Finally, there is a rather powerful fascicle arising from the
cartilaginous nose, going forwards, and inserting itself into the
lower and lateral face of the anchor-shaped cartilage.

Facial muscles of Elk. Wapiti. 58

6. M. rectus nasi

forms a system of closely packed, and rather thin fascicles from the
mucous membrane of the nose to the skin. They occupv the
space of the soft nose behind the nostril, where they, especially
in the arched portion, form a thick mass of bundles which cross
out between the nasolabialis-fascicles (PI. 11, fig. 1).

3. WAPITI.

i. Platysma-sphincter-group.

The sphincter superficialis is wanting on the head.

The platysma is present in a particularly well developed
form, viz. as a large continuous muscular plate, which on the
ventral face of the head (the regio submandibularis) reaches so
far towards the median line that the posterior part is only separated
from the corresponding part of the other side by a quite
narrow tendinous line, whereas they unite completely in front.
The platysma covers a very great part of the lateral surface of
the face, e. g. the whole masseter, and reaches here up below
the ear, so that the bundles in front of this radiate upwards,
above the zygoma. Farther on upon the face, bundles reach up
to — some partly a little above — the lower margin of the pars
zygomatica platysmatis. Some bundles thrust into the buccinator,
but most extend to the very angle of the mouth, and into the
under lip.

The pars zygomatica is quite separated from the rest of the
platysma, and arises with a long narrow tendon from the zygoma.
The muscular body is rather broad, but short, and making for
the angle of the mouth, where the lower bundles end thrusting
between the rimana-bundles, whereas the upper ones proceed
into the upper lip.

The sphincter profundus consists of the same two separated
portions as in the Elk. The auricular portion may be divided
into an upper and a lower part. The lower part forms quite a
considerable muscular plate on the anterior part of the ventral face
of the neck1). Real sphincter-shaped bundles we could not make
out. In the median line the bundles from the two sides are interlaced
and pass thence obliquely forward and upward, turning
on to the lateral face of the neck; the anterior bundles reach so
far on that they turn up in an arc round the angle of the lower
jaw; reaching some distance across the lower part of the masseter.
The upper part of the auricular portion is rather narrow; it extends
from the base of the auricle down across the parotis spreading
like a fan; some of the anterior and posterior bundles proceed
direct in the bundles of the lower part described above, while
other bundles terminate about level with the angle of the lower jaw;
but are connected with the lower part by a thin aponeurosis. —
The palpebral portion is powerfully developed; it forms a large,
broad, flat, muscular body which arises from the lower eyelid
and from the skin in the lower circumference of the lachrymal
groove. From here the muscular body stretches downward over
the masseter, and the buccinator, passing into a thin aponeurosis
that is connected with the lower part of the auricular portion.
In the anterior part of the palpebral portion there is a narrow
streak of bundles directed obliquely upwards and forwards. The
direction quite corresponds with that of the anterior bundles of
the lower part of the auricular portion.

2. Orbicularis-oculi-group.

PI. 16, fig. 24.

The m. orbicularis oculi, which is rather narrow, consists of
circular bundles. Dorsad to these there is in the upper eyelid
also a rather broad tract of bundles — so broad that it projects
somewhat over the bony orbita — which arise at the anterior
angle of the eye, running in a bow backwards, turning behind
the posterior angle of the eye and ending here fan-wise. These

*) How far it posteriorly reaches on the neck we cannot decide, as the head
with the anterior part of the neck was cut off for the sake of preservation.

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