=M. depressor conchæ= (Fig. 64, _b_).--A thin band of fibres, caudad of
the last and parallel with it. The muscle arises as scattered fibres on
the ventral surface of the neck, one or two centimeters craniad of the
manubrium, the fibres of the muscles of opposite sides crossing the
middle line and interdigitating. They pass dorsad, gathering together to
form a narrow band which is inserted into the summit of the antitragus.
_Relations._--Outer surface with the skin at the ventral end, and with
the platysma (_a′_) further dorsad. Inner surface with the deep muscles
of the neck and with the parotid gland.
_Action._--Draws the external ear ventrad.
Lying deeper than the muscles thus far described, but closely connected
with a number of them, are the following:
=M. frontoscutularis.=
_Origin_ (Fig. 63, _o_) on the frontal bone, along the supraorbital
margin, from the craniomedial angle of the eye caudad to the zygomatic
process of the frontal.
The fibres form a large muscle which passes dorsocaudad to the scutiform
cartilage and is mostly attached along its ventrolateral border. Some of
the outer fibres, however, pass distad of the scutiform cartilage toward
the cartilage of the ear, thus joining the adductor auris superior
(_f_).
The outer surface of this muscle is closely connected with fibres of
the intermedius scutulorum (_a_), the corrugatores supercilii medialis
(_b_) and lateralis (_d_), and the frontoauricularis, when this exists.
The outer surface is covered near the origin by the orbicularis oculi
(_c_), farther dorsad by the muscles just mentioned and the integument.
The inner surface is in relation with the frontal bone and the adductor
auris inferior (Fig. 64, _o_).
_Action._--Pulls the ear craniad.
=M. adductor auris inferior.= (Fig. 64, _o_.) (Part of the auricularis
anterior of man.)--A small muscle lying beneath the frontoscutularis.
_Origin_ on the ligament which connects the zygomatic process of the
frontal with the frontal process of the malar. The fibres form a thin
band about 7 millimeters wide which passes craniad, closely united to
the inner surface of the frontoscutularis. At the caudal edge of the
zygomaticus (_d_) the muscle is interrupted by a short tendinous
interval; the fibres then continue to their insertion on the tip of the
antitragus.
_Relations_.--Outer surface with the frontoscutularis, the zygomaticus
(_d_), and the integument. Inner surface with the temporal muscle and M.
antitragicus (_n_).
_Action._--Pulls the ear craniodorsad.
* * * * *
The remainder of the muscles of the ear, which, with the exception of
the tragicus lateralis, merely interconnect the cartilages of the
external ear or parts of these cartilages, are described in connection
with the account of the Auditory Organ.
* * * * *
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