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Appendix.

Facial muscles of Tapir.

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at a distance outside the lateral margin of the nasal bone, in a
posteriorly convex line. Down the maxillary bone the aponeurosis
gradually grows more and more narrow, and the undermost
fascicles arise direct from the lig. palpebrale. The muscular
body is flat, broad, and rather powerful and extending on to the
lateral face of the trunk. The fascicles run obliquely downwards
and forwards; the dorsal fascicles are the longest and reach out
to the dorsal circumference of the nostril. The following fascicles
gradually decrease in length; they insert themselves into the
lateral and ventral circumference of the nostril, whereas the fascicles
of the posterior part of the muscle go obliquely down into
the upper lip, along its whole length thrusting inside the pars
rimana. The hindmost fascicles have a direction from the anterior
angle of the eye (the lig. palpebrale) almost towards the
angle of the mouth, joining the anterior ventral fascicles of the
m. prseorbicularis so intimately that no limit can be set between
these two muscles. Above, on the dorsum of the nose, the
aponeurosis is covered by the m. supraorbicularis, whereas the
part in front of the eye is covered by the dorsal prseorbicular
fascicles.

The m. nasolabialis covers a great part of the m. maxillo-
labialis. As to the lower portion of the m. maxillo-labialis it
appears on the lateral face of the trunk, dorsad to the m. nasolabialis
(PI. 7). At first the two muscular bodies are to be distinguished
plainly from each other, the dorsal fascicles of the
lower portion of the m. maxillo-labialis running obliquely forwards
and upwards; but afterwards, the fascicles of the latter
increase in length, bending more and more downwards, and at
last joining the dorsal margin of the m. nasolabialis so intimately,
that in front, on the trunk, no limit whatever can be seen between
the two muscles (comp. PI. 14, fig. 3).

3. M. maxillo-labialis.

PL 8, fig. 2, and PL 7.

The two portions of the m. maxillo-labialis are separated as
two distinct muscles. The portio superior is a powerful muscle
which arises with quite short tendons (partly fleshy) in front of
and above the orbita, in a line from the frontal bone on to the
maxillary and the lacrymal bones, almost down to the lig. palpebrale
. On the frontal bone the origin is from the crest which
this bone sends up laterad to the cartilaginous nasal capsule.
Being broad and flat at the origin it soon contracts into a narrow
but rather full muscular body that turns in an arc on to the
dorsal face of the trunk, reaching, a little in front of the cartilaginous
nose, to the median line, and blending with the corresponding
muscle of the other side (PI. 14, fig. 3); it may be
followed on the dorsal face of the trunk to the very end (a distinct
groove is formed on this face for the muscle to lie in).
Gradually it grows narrower, producing flat, thin, aponeuroses that
insert themselves into the dorsal face of the trunk, and ends in a
narrow tendon that can be followed to the very end of the trunk
(inserting itself into the skin dorsally in the median line). —
The posterior end of the muscular body is completely covered
by the m. nasolabialis.

The portio inferior arises with a flat, not very broad, rather
powerful aponeurosis, from the maxillary bone below the foramen
infraorbitale, so that it is separated from the origin of the portio
superior by a rather considerable interval. From the aponeurosis
the fascicles radiate on to the lateral surface of the trunk, to a
great extent covered by the nasolabialis. The origin itself is
covered partly by this muscle partly by the ventral fascicles of
the m. prseorbicularis. The muscular body of the portio inferior
is flat and flabellate. Its uppermost fascicles run obliquely upwards
and forwards crossing the fascicles of the nasolabialis; the next
fascicles increase in length, going more and more in upward arcs,
so that, as to direction they closely join the fascicles of the nasolabialis
(v. above). The fascicles of the portio inferior radiate
partly up towards the dorsal face of the trunk, partly forwards
on its lateral surface, where they can be followed towards the
dorsal and lateral circumference of the nostril.

4. Buccinator-group.

PL 16, fig. 9, 10, 11; PI. 8, fig. 2; PL 7.

The m. buccinatorius at its origin from the upper and lower
jaw, forms a single layer of longitudinal fascicles (PI. 8, fig. 2);
but a little farther on the upper fascicles alter their direction
running transversally downward, so that the m. buccinatorius
throughout the greater part of its length consists of a superficial
transverse, and a deep longitudinal layer. The transverse fascicles
, however, do not form a continuous layer throughout;
about midway there is a discontinuity whereby the longitudinal
layer become exposed. This discontinuity is, by the way, mostly
filled by the portio palpebralis m. sphincteris profundi (v. above).
Towards the angle of the mouth the fascicles of the transverse
layer are more closely set and proceed directly into the broad and
powerful pars rimana, which does not unite in front with that
of the other side. On the trunk the anterior part of the pars
rimana, which ends at the ventral side of the nostril, cannot be
distinguished from m. nasolabialis (comp. PI. 14, fig. 3).

The longitudinal layer of the buccinator is very strongly
developed and forms a continuous layer, the uppermost fascicles
of which can be traced for some distance into the upper lip;
the next reach to the angle of the mouth (PI. 8, fig. 2), and the
undermost insert themselves into the mucous membrane of the
cheek.

Some of the uppermost and deepest fascicles of the longitudinal
layer run in a curious, odd way, since they bend downwards
in front (PI. 16, fig. 11), so that for a space of 4—5 cm behind
the angle of the mouth there is a portion where the buccinator
seemingly appears with three layers.

The pars supralabialis (PI. 8, fig. 2) takes its origin from the
maxillary bone and extends into the upper lip inside the pars
rimana; it has no connection with the longitudinal fascicles of
the buccinator and presents only a limited area in the shape of
a small muscular plate behind the middle of the length of the
upper lip; the inferior ends of its fascicles are directed somewhat
forward.

No depressor labii inf. is formed as a distinct muscle;
nevertheless we must here add the following: In front, at the
lower margin of the transverse layer, there is a tendinous portion
(PL 8, fig. 2) into which some platysma-fascicles and the
portio palpebralis m. sphincteris profundi insert themselves. From
this tendinous portion there arises a tract of longitudinal fascicles
that thrust into the under lip; but upwards they join the
pars rimana so closely (PI. 7) that no limit whatever can be
shown between them.

The m. nasalis forms a rather considerable muscular mass
that arises along the upper margin of the maxillary bone radiating
upwards; in PI. 8, fig. 2 the upper fascicles are seen above the
portio inferior of m. maxillo-labialis. The whole forms a flat
muscular body with rather thin fascicles imbedded in a somewhat
solid intramuscular connective tissue. The fascicles have
not quite a dorsad direction, but are running obliquely dorso-
caudad, and are regularly disposed in series or blades. From
their origin on the bone they pursue an arcuate course below the
nasal tube, and are then turned upwards onto the lateral face
of the soft nose, where they end.

The m. mentalis is a rather considerable muscular mass that
arises from the anterior part of the lower jaw and radiates with
its fascicles out to the skin crossing out between the rimana-
fascicles. The fascicles lie imbedded in a rather plentiful mass
of adipose connective tissue; in PI. 8, fig. 2 the fascicles cut
through are seen in the adipose tissue above the part of the
rimana that is still preserved.

5. M. rectus nasi et labiorum.

PI. 14, fig. 3; PL 8, fig. 2; PL 7.

The m. rectus nasi forms a very considerable system of thin
fine fibres which radiate out from the whole circumference of
the nasal tube. They arise from the mucous membrane of the

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