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Appendix.

Facial muscles of Zebu. Boar.

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fascicles form a continuation of the upper longitudinal fascicles
of the intermediate layer, and proceed in the usual way into the
upper lip, where they, however, on account of the gingiva not
extending far up, only form a low arc.

In front, from the intermaxillary bone, there arises a rather
considerable muscular mass (»grosser Erweiterer der Nasenl6cher«,
»/7?. dilatator naris apicalis« of the Veterinary anatomy) whose
fascicles radiate upwards and insert themselves into the ventral
and mediad circumference of the nostril. The whole forms a
rather full muscular body, that in the median plane closely joins
the corresponding one. The limit between them, is indicated by
a groove. This muscle is apparently an independent muscle,
but a comparison with the Elk, and the Wapiti, shows that it
no doubt corresponds to the anterior part of the rather singularly
shaped pars supralabialis m. buccinatorii of the Elk (comp. PL
16, fig. 4).

The m. nasalis is strongly developed, and forms quite a considerable
muscular mass, which arises from the intermaxillary
bone and, in front, also from outside the soft nasal wall. The
fascicles radiate up into the whole region behind and laterad of
the nostril, inserting partially into its lateral and posterior circumference
, partially into the skin of the upper lip. The fascicles
arise in rows, by degrees higher and higher up, from the intermaxillary
bone, which may easily be shown by dissecting down
between the rows, in this way separating them from each other.
The whole, however, forms a continuous muscular mass through
which the tendinous branches of the m. maxillo-labialis proceed.
The posterior part of the m. nasalis forms a rather broad flat
bundle which extends obliquely upon the intermaxillary bone
thrusting in between the bundles of the m. nasolabialis.

The m. mentalis forms rather a considerable muscular mass
that arises from the lower jaw, with fascicles arranged in numerous
rows, one below the other. They radiate into the under
lip and the chin.

The fascicles are very coarse both in the m. mentalis and
in the m. nasalis.

5. M. lateralis nasi

forms a flat but rather extensive muscular body that arises from

the anterior margin of the proc. nasalis of the intermaxillary bone,

extending outside the soft nose and inserting itself into the outside

of the mucous membrane.

From the cartilaginous nose arises a muscle which radiates
with its bundles upwards and outwards to the mediad, posterior
and lateral circumference of the nostril.

6. Mm. recti.

M. rectus labii is at any rate present in the under lip, where
the fascicles, moreover, are so coarse that they may be seen with
the naked eye; they go, in the usual way, from mucous membrane
to skin, crossing between the fascicles of the m. mentalis.

5. BOAR.

1. Platysma-sphincter-group.

PI. 9 and PI. 10, fig. 3.

The sphincter superficialis arises as a continuous, rather narrow
, but full muscular body; partly from an aponeurosis outside
the sternal muscles, but partly, and mostly, from the anterior end
of the sternum, where in the median line it joins the corresponding
muscle of the opposite side. The muscular body stretches
upwards and outwards on the ventral face of the neck, turning
with its longest fascicles (viz. the dorsal ones) a little on to
the lateral surface of the neck. The muscular body spreads fan-
wise, thereby growing gradually thinner, but still forming a
closely united muscular plate.

As the muscular body turns from the ventral to the lateral
face of the neck it meets the lower margin of the platysma, and
is thereby split into two portions. The posterior and, also, the
broader portion proceeds outside the platysma (v. PL 9) and the

fascicles end in short tendons that thrust into the subcutaneous
adipose tissue. This adipose tissue extended also somewhat down
between the fascicles, so that the latter, for some space, were
quite surrounded by it. — The anterior portion (v. PL 10, fig. 3)
is much narrower, and thrusts up under the platysma, where
most of its bundles end in the adipose tissue inside the latter,
about level with the margin of the lower jaw. A few of the
posterior and deeper fascicles, however, turn in an arc into the
portio auricularis of the sphincter profundus.

The platysma forms a powerful, broad and thick, continuous
muscular plate that arises from a strong aponeurosis outside the
muscles of the shoulder, extending across the face, and also,
spreading into the regio submandibularis. Of the fascicles, which
are very coarse, the upper turn in an arc up over the posterior
part of the masseter, reaching up to the zygoma. Gradually they
take the longitudinal direction and run with a slight downward
convex curve upon the face where, in a long slanting line, they
thrust themselves into the buccinator. The lower of these longitudinal
fascicles reach to a transverse plane through the angle
of the mouth. The fascicles partly insert themselves on the mucous
membrane of the cheek, and partly (the anterior ones) reach
the angle of the mouth and the under lip where they join the ri-
mana-fascicles. Finally, we come to the lower part of the platysma
. Here part of the bundles insert themselves into the lower
jaw (v. PL 9) whereas most turn round the margin of the jaw
into the regio submandibularis where, in a »raphe«-like stripe
they join the platysma-fascicles from the other side, in front inserting
themselves into an aponeurosis that extends to the angu-
lus mentalis.

The pars zygomatica (PL 9) forms an independent muscle
without any connection whatever with the rest of platysma. It
arises with a long narrow tendon from the zygoma stretching
obliquely downwards and forwards and thrusting in below the
superficial layer of the buccinator at a considerable distance behind
the angle of the mouth. The fascicles can be followed on
to this. The muscular body itself is short and thin. Both the
tendon and the muscular body are rather closely connected with
some fascicles of the portio palpebralis of the sphincter profundus.

The sphincter profundus is present in the shape of two portions
quite separated from each other.

The anterior one, the portio palpebralis (PL 9), arises from a
thin aponeurosis inside the platysma. The muscular body is
lamelliform, thin, and rather pale; its posterior fascicles run up
into the lower eyelid where they mingle with the orbicularis-
fascicles. The anterior ones reach so far on that they thrust up
between the ventral prseorbicular bundles. The very hindmost,
rather short fascicles of the palpebral portion arise from the
tendon of the pars zygomatica platysmatis; and a couple of the
foremost fascicles turn in an arc forwards, joining its muscular
body.

The portio auricularis (PL 10, fig. 3), at its origin from the
base of concha auris, forms a round, rather full muscular body,
which was quite surrounded by adipose tissue. As the muscular
body runs downwards it splits into two portions: an anterior
spreading down over the masseter and the anterior part of the
parotis, — and a deep one, which is very interesting. It runs
down as a narrow muscular chord inside the parotis, between
the latter and the gl. submaxillaris; the anterior fascicles end
about level with the margin of the lower jaw, turning in an arc
forwards and partly thrusting in between the bundles of the anterior
portion of the sphincter superficialis. The posterior fascicles
on the contrary proceed downwards passing direct into the
sphincter superficialis.

2. Orbicularis-oculi-group.

PI. 16, fig. 25, and PI. 9.

The m. orbicularis forms a rather broad muscular border both
in the upper and lower eyelid, consisting of circular fascicles
that arise from and insert themselves into the anterior angle of
the eye.