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Appendix.

Facial muscles of Zebu.

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a rather broad continuous muscular body which, from the upper
part of the neck, and from the regio submandibularis, turns on
to the face, where with longitudinal fascicles it makes for the
angle of the mouth. Here most of the fascicles end; whereas
only a small part proceed into the lips. The upper part of the
platysma sends its bundles, fan-wise, up over the masseter and
the pars zygomatica. The bundles lie gathered in rather broad
bands, that radiate over the said muscles and are held together
by a thin aponeurosis. They reach so high up that they thrust
between the fascicles of the orbicularis oculi and the postorbi-
cularis. Altogether the whole of the platysma body forms a
muscular plate with radiating bundles, where quite a smooth
transition is found from the posterior bundles, which radiate
almost transversally, to the anterior longitudinal ones.

The pars zygomatica behaves in the main as in the Wapiti
but is more powerful.

The m. sphincter profundus behaves in the main as in the
Camel; still both portions are broader and more powerful than
in the latter.

2. Orbicularis-oculi-group.

PI. 16, fig. 23.

The m. orbicularis oculi is made up, in the region nearest the
palpebral margin, of sphincterial fascicles that arise from, and
insert themselves into, a long and powerful lig. palpebrale nasale.
These are, in the upper eyelid, joined by fascicles that arise from
the ligamentum, turn in an arc backwards behind the posterior
angle of the eye, and end below it, spreading fan-wise. As a
continuation of these fascicles there is a quite powerful m. post-
orbicularis, the bundles of which gradually increase in length posteriorly
, so that they here extend to the actual frontal surface,
where they thrust up partly below, partly between the bundles
of the m. supraorbicularis. As in the Elk and in the Wapiti
there is also in the Zebu, at the posterior angle of the eye, a
band of longitudinal fascicles which, in the main, behaves as in
those two animals, only it is more powerful in the Zebu: m.
horizontalis (not figured in PI. 16, fig. 23).

The m. prceorbicularis is most powerfully developed. As in
the deer described, there are, at the anterior angle of the eye,
fascicles that radiate dorsad and ventrad; the fascicles are numerous
, and form two broad, flat, rather full muscular bodies;
this especially holds good of the ventral fascicles.

The 777. supraorbicularis is large and powerful, forming a
bulky, flat muscular body, which from the anterior angle of the
eye — where it is closely connected with, and forms a direct continuation
of, the praeorbicularis dorsalis — and from the upper eyelid
, in its whole length, radiates upon the frontal surface. Here
it forms a broad, flat muscular body which covers the whole
frontal surface (the »m. frontalis« of the Veterinary anatomy).
The anterior fascicles radiate upon the front, but the following
gradually bend more and more backwards, so that they become
longitudinal in the posterior part of the muscular body.

The 777. nasolabialis is rather weak; it shows its connection
with the orbicularis complex by the fact that some of the dorsal
prseorbicularis fascicles turn down into it; these fascicles are
joined by others, that come from the dorsum of the nose, running
obliquely downwards and forwards. The fascicles go partly
to the posterior circumference of the nostril, partly down into
the upper lip. The muscular body proceeds over the cartilaginous
nose, but is indeed here very thin, and pale. In this anterior
portion the bundles have a quite transversal direction. The tendinous
branches of the maxillo-labialis project from among them,
and are used for insertion by some of the nasolabialis-bundles.

3. M. maxillo-labialis

arises partly fleshy partly with short tendinous bundles from the
maxillary bone, below and behind the foramen infraorbitale. From
its origin the muscular body is, by a deep but narrow fissure,
which is filled with connective tissue, divided into an upper and

a lower portion; both of them are powerful, especially the lower
one; which forms a full plump muscular body. The upper portion
divides into three branches, each with a tendon, of which
the upper, which is also the most powerful, turns up over
the cartilaginous nose inserting itself into the muzzle with several
tendinous radiating slips, whereas the two lower ones, each
of which also splits into several branches, insert themselves along
the posterior circumference of the nostril. The lower portion proceeds
into the upper lip also dividing into several tendinous
branches under way. From a couple of tendinous branches there
come small muscular portions that project between the fascicles
of the m. nasalis.

4. Buccinator-group.

PI. 16, fig. 7 and 8.

The 777. buccinatorius is very complicated in its structure;
the bundles may be dissected out into three »layers«. At its
origin, posteriorly, from the upper and lower jaw it behaves in
the main as in the Elk. That is, it forms here only one layer;
but the stratification of the muscle arises as the lower and the
deep bundles partly continue the longitudinal direction, partly
bend upwards and thrust in below the upper ones, which have
gradually taken a perpendicular direction. This stratification
begins much farther back in the Zebu than in the Elk. In the
greater length of the m. buccinatorius three layers may be distinguished
: of which the superficial one and the intermediate are
separated from each other by a rather thick layer of adipose tissue,
in which very numerous gl. buccales are imbedded. The ductus
parotideus does not pierce the m. buccinatorius: a little in front
of the m. masseter there is above the buccinator a small portion of
mucous membrane which is quite without muscular fibres; here
the salivary duct pierces the mucous membrane.

The superficial layer (PI. 16, fig. 7) consists of transverse
bundles that at the angle of the mouth proceed into the pars
rimana, which is rather powerful but does not form a »sphincter«,
the bundles only reaching halfway into the lips, where they insert
themselves into the median fibrous part of the latter. Along
the lower margin of the superficial layer there is a broad and
rather full 777. depressor labii inferioris, the bundles of which proceed
longitudinally and thrust into the under lip and the chin. This
depressor plainly shows its connection with the superficial layer
of the buccinator, the posterior bundles turning from the latter
direct into the m. depressor; these bundles are joined by others
that emerge between the transverse bundles but in the deeper
parts join them quite closely. Below this layer there is the intermediate
, longitudinal one (PI. 16, fig. 8). Its fascicles, however,
are by no means so regularly arranged as is generally found in
the longitudinal layer. Along the upper and lower margin of the
layer there is a tract of longitudinal fascicles, part of which
under way insert themselves into the mucous membrane, whereas
others reach into the upper and under lips, and contribute
to the formation of the pars rimana thrusting between its
bundles. But between these two longitudinal tracts there is a
broad stripe, where the fascicles rather soon take a slanting direction
, downwards and forwards, in order to turn forwards
again in the longitudinal direction towards the angle of the mouth
where they end.

Deepest of all — immediately on the mucous membrane of
the cheek — there is a third layer (not figured in PI. 16) which
posteriorly takes its origin from the deepest longitudinal fascicles.
In front, the latter gradually bend upwards in a more and more
slanting direction, and are continued forwards to about the angle
of the mouth, by bundles that are directed obliquely upwards
and forwards. They arise from, and insert themselves into, the
mucous membrane, upwards partly thrusting between the fascicles
of the upper longitudinal band of the intermediate layer.

In the upper lip there is a pars supralabialis. This does not
extend through the whole length of the upper lip, reaching in
front about below the middle of the nostril, and posteriorly to
a couple of centimetres in front of the angle of the mouth. The

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