390 THE HORSE. 
most important being those which connect the trunk with the extremities, 
they will be selected as more especially deserving attention. 
LATERAL CERVICAL REGION. 
SPLENIUS is situated on the superior part of the neck. Origin—from - 
the three anterior dorsal spines. Jnsertion—to the mastoid process of the 
petrous portion of the temporal bone, crest of the occiput, wing of the 
atlas, transverse process of the second, third, fourth, and fifth cervical 
vertebra, and to the lateral parts of the ligamentum colli. Action—to 
draw the head on one side, when one muscle acts ; when both together, to 
erect the head. 
CoMPLEXUS MaJoR is situated under the splenius. Origin—from the 
transverse processes and spines of the six anterior dorsal vertebree. Jn- 
sertion—to the oblique processes of all the cervical vertebra, wing of the 
atlas, tubercle on the occipital crest, lateral parts of the ligamentum colli, 
and by blending with the tendon of the splenius to the mastoid process of 
the petrous portion of the temporal bone. Action—to erect the head. 
TRACHELO MASTOIDEUS is deeply seated under the splenius. Origin— 
from the transverse processes of the two anterior dorsal spines. Jnsertion 
—to the oblique processes of all the cervical vertebree, wing of the atlas, 
and mastoid process of the petrous portion of the temporal bone. Action 
—similar to the splenius. 
SpINALIS COLLI lies close to the bodies of the vertebra, between their 
oblique and spinous processes. Origin—from the oblique processes of the 
five posterior cervical vertebrae and the first dorsal. Jnsertion—to the 
spinous processes of all the cervical vertebrae but the atlas. Actvon—to bend 
the neck upwards and backwards. 
INFERIOR CERVICAL REGION. 
STERNO-MAXILLARIS is situated on the inferior part of theneck. Origin 
—from the supero-anterior part of the cariniform cartilage. Insertion— 
(opposite the thyroid body it becomes tendinous) to the posterior angle 
of the inferior maxillary bone. Actvon—to depress the lower jaw, and, 
through it, the whole head. ; 
STERNO-THYRO HYOIDEUS is situated above the sterno-maxillaris, Origin 
—from the infero-internal part of the first rib, and from the supero-anterior 
part of the cariniform cartilage. Insertion—half-way up the neck it 
bifurcates, one part going to the postero-external part of the body of the 
thyroid cartilage, the other to the spur process of the os hyoides. Action 
—to draw the tongue and larynx backwards and downwards. 
SUBSCAPULO HYOIDEUS is situated on the antero-superior part of the 
neck. Ovigin—from the supero-internal part of the body of the humerus, 
just below the inner tubercle. Jnsertton—to the under side of the root 
of the spur process of the os hyoides. Action—to depress the os hyoides, 
or, if that is fixed, to aid the last muscle in lowering the head. 
SUPERIOR CERVICO-OCCIPITAL REGION. 
Five patrs of small and short muscles connect the atlas and dentata 
with the head, occupying the space known as the poll. These are com- 
plexus minor, rectus capitis posticus major and minor, obliquus capitis 
superior and inferior. Their action is to raise the head and preserve the 
union of the bones intact. 
