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Appendix.

Facial muscles of Tapir.

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The muscular body now turns upwards, round the margin
of the lower jaw, and radiates upon the face, covering a great
part of the masseter and making for the angle of the mouth
and the under lip. On a single spot above the lower part of
the masseter there is an interruption in the muscular body about
3—4 cm high and about 1 cm broad, filled by a plate of adipose
connective tissue.

On the face the fascicles run obliquely forwards, in the
posterior part also upwards, that is, the whole muscular body
forms a plate extended fan-wise. At the insertion the platysma-
fascicles, as it were, separate into three portions, a separation
that is produced in the following way: The upper margin of the
muscular body ends in a line which goes from the zygoma obliquely
forwards and downwards, towards the under lip, at first following
the lower margin of the pars zygomatica; but a middlemost portion
of the muscular body, about 3—4 cm broad, proceeds
farther forwards, a rather great distance in front of this slanting
line of insertion. In this way the insertion of the platysma is
divided into three portions. The intermediate portion (b, PI. 7)
runs obliquely forwards towards the angle of the mouth and a
little behind the latter the fascicles thrust between the fascicles
of the m. buccinatorius. This portion, in front, joins the pars
zygomatica so intimately that they apparently form a continuous
muscular body. A close investigation of the course of the fascicles
in this intermediate portion shows that it is only the lower
fascicles that so intimately join the lower margin of the pars
zygomatica as to form a direct continuation of it, whereas the
rest partly dip below, partty cross between, the fascicles of the
pars zygomatica, and radiate towards the upper lip, together
with them, but covered thereby.

The fascicles of the uppermost portion (a, PI. 7) of the platysma
end along the lower margin of the pars zygomatica, here
passing into a thin fascia that proceeds up over this muscle.
The undermost portion (c, PI. 7) joins the m. buccinatorius. It
makes for the lower margin thereof at a rather considerable
distance behind the angle of the mouth (corresponding to a plane
through the anterior angle of the eye). Here is a tendinous
portion of the buccinator, and into this the superficial fascicles
of the undermost portion of the platysma insert themselves.

The pars zygomatica forms a distinct, rather powerful muscle,
which arises with a short aponeurosis from the anterior part of
the zygoma running forwards in a downward convex arc. The
fascicles partly end at the angle of the mouth where they thrust
between the fascicles of the pars rimana together with the
fascicles from the intermediate portion of the platysma, and they
partly radiate upwards, towards the upper lip, being interwoven
between the fascicles of the m. nasolabialis.

The m. sphincter profundus. Of this muscle the portio au-
ricularis is present in the shape of a real sphincter that from
one side of the head turns in an arc below the anterior part of
the neck on to the other side. It inserts itself on the outside
of the base of the auricle, so that the muscular body partly
forms a sling from one auricle to the other. This sphincter-
shaped arrangement of the fascicles however only applies to
about the posterior half of the muscle. On the ventral face of
the neck the sphincter is rather broad with plenty of adipose
intramuscular connective tissue between the fascicles; but as
soon as it turns on to the parotis it decreases considerably in
breadth, the fascicles closing near together. In front the muscular
body proceeds in a rather powerful fascia that extends on the
face inside the platysma (most of the fascia has been dissected
off in PI. 7), and from this fascia all the anterior fascicles of the
auricular portion arise. They arise in a straight line drawn perpendicularly
down through the middle of the maxillary joint, the
upper fascicles taking their origin close below this articulation
. All the fascicles coming from the fascia intimately join
the posterior ones. If the fascicles be traced from the insertion
of the muscle on the auricle it will be found that the anterior
ones run at first perpendicularly downwards, and then turn in
an arc forwards, close below the maxillary joint. The succeeding
fascicles radiate more and more obliquely downwards, and the

posterior ones run straight downward, only on the neck spreading
fan-wise. The auricular portion, altogether, forms a broad
strong muscular plate with rather coarse fibres.

Below the e}^e there is a flat portion of muscular fibres
about iy2 cm broad (vide PI. 8) that arises from the tendinous
portion of the buccinator, into which part of the fascicles of the
platysma insert themselves (comp. PL 7). The fascicles run upwards
, at first quite closely joining the transverse fascicles of the
buccinator, but gradually they separate from them and now
ascend as a continuous muscular body towards the lower eyelid
, where they thrust between the orbicular and prseorbicular
fascicles. The relations between this muscular body and the orbicularis
correspond exactly to those found in the portio pal-
pebralis m. sphincteris profundi of the other Ungulates, for which
reason we are of opinion that this muscular body in the Tapir
must be regarded as the portio palpebralis, which then, secondarily
, at its origin has more closely joined the m. buccinatorius.
The muscular body is mostly covered by the pars zygomatica
and the platysma proper (comp. PL 7 and 8; in PL 7 the fascicles
of the portio palpebralis are seen projecting above the upper
margin of the pars zj^gomatica).

2. Orbicularis-oculi-group.

PI. 7 and PI. 16, fig. 27.

The m. orbicularis oculi with the m. pra3- and postorbicularis
forms a broad ring round the eye; but in front, between the
dorsal and ventral prseorbicular fascicles, there is a notch quite
filled by the m. nasolabialis. The whole muscular group appears
as a continuous whole.

The orbicular fascicles arise from a broad, thick, and powerful
lig. palpebrale nasale running in an arc through the lower
eyelid, and turning up behind the posterior angle of the eye
into the upper eyelid unto the same ligamentum. The whole
forms a rather powerful, broad, ring, so broad that it reaches
beyond the bony entrance of the orbita.

The m. prceorbicularis arises from the lig. palpebrale and
radiates dorsad and ventrad. Dorsally there is formed a thick
fan-shaped portion that covers the anterior part of the orbicular
fascicles of the upper eyelid, and a rather considerable part of
the origin of the m. nasolabialis. — The ventral fascicles are
numerous, and radiate downward, and so form a great, flat, fan-
shaped muscular body, posteriorly joining the orbicular ones in
the lower eyelid, so closely that no limit can be shown. In front,
also without any traceable limit, they join the m. nasolabialis.

The m. postorbicularis forms a rather broad tract of fascicles
that run down along the posterior circumference of the orbicularis
, lying close to it. The fascicles extend, both above and
below, far beyond the orbicularis. Posteriorly the curve gradually
straightens somewhat, so that the posterior margin of the
muscle forms an almost straight line, which only towards the
ends, bends a little forwards. This posterior margin extends for
some considerable distance on the m. temporalis being separated
therefrom by a thick layer of adipose tissue.

Dorsally there is another, flat, broad, but rather thin muscular
body that arises high up, partly from the nasal bone, partly
outside the cartilaginous nose, stretching down inside the dorsal
prseorbicular fascicles, and ending in the upper eyelid. Judging
from its situation — particularly its relations to the upper eyelid
— this muscle must certainly be regarded as the m. supraor-
bicularis, although, indeed, it does not, as in the other Ungulates,
appear as a direct continuation of the prseorbicularis dorsalis
but rather as a deeper layer of it.

The m. nasolabialis arises with a broad aponeurosis which
begins upon the dorsum of the nose where it is interwoven with
the periost of the nasal bones. From this point the aponeurosis
stretches across the cartilaginous nasal capsule and then further
takes origin from the maxillary bone, in the region in front of the
orbita down to the lig. palpebrale, with which it amalgamates.
The part of the aponeurosis arising from the dorsum of the nose
is broad, so that the muscular fascicles arise from the aponeurosis