The =trapezius= is very wide, its line of origin extending from the
occipital bone to the tenth thoracic vertebra. There is no clear
division between its two parts, which are both inserted into the
scapular spine.
The =omo-transversarius= resembles that of the ox.
The =rhomboideus= consists of three portions. The =cervical portion=
(Rhomboideus cervicalis) is greatly developed, its origin extending from
the second cervical to the sixth thoracic vertebra. The =cephalic
portion= (Rhomboideus capitis) arises with the splenius on the occipital
bone, and is inserted with the cervical part. The =dorsal portion=
(Rhomboideus thoracalis) extends as far back as the ninth or tenth
thoracic vertebra.
The =latissimus dorsi= is attached to the four ribs preceding the last.
It is inserted into the internal lip of the bicipital groove.
The =mastoido-humeralis= divides into two parts, the =cleido-mastoideus=
and =cleido-occipitalis=, which arise on the mastoid process and
occipital crest respectively, and unite at the fibrous vestige of the
clavicle.
The =anterior superficial pectoral= is thin. The =posterior superficial
pectoral= is divided into parts, one of which ends on the humerus, the
other on the fascia of the forearm.
The =deep pectoral= is clearly divided into two parts. The =scapular
portion= resembles that of the horse, but its origin does not extend
behind the first two chondro-sternal joints. The =posterior deep
pectoral= is very long.
The cervical portion of the =serratus magnus= is greatly developed, its
origin extending from the wing of the atlas to the upper part of the
fifth rib, and passing under the thoracic portion; the latter resembles
that of the ox.