ANATOMY OF THE HORSE. 
3 
sphenoid, and to the palate bone : inferiorly, to the pharynx—its 
fibres intermixing and confounding themselves with those of the 
hyo-pharyngeus and stylo-pharyngeus. 
Direction .—The reverse of the former muscle: viz. from above, 
downwards; and from before, backwards. 
Action ,—To assist in the dilatation of the pharynx. 
STYLO-PHARYNGEUS. 
Situation ,—Postero-lateral part of the pharynx. 
Attachment .—Posteriorly, to the styloid process of the tem¬ 
poral bone, and outer side of the cartilage of the Eustachian 
tube : anteriorly, to the side of the pharynx. 
Structure .—Tendinous at its origin : remainder, fleshy. 
Action .—To assist in dilatation, by drawing the side of the 
bag in a direction upwards and backwards. 
constrictor pharyngis anterior. — Hyo-pharyngeus . 
Situation .—Antero-superior part of the pharynx. 
Attachment ,—Inferiorly, antero-intemal part of the comer of 
the os hyoides ; superiorly, to a tendinous line uniting it with its 
fellow along the mesio-anterior part of the pharynx.' 
constrictor pharyngis medius.— Thyro-pharyngeus. 
Situation .—Behind the former muscle. 
Attachment, —Inferiorly, lateral parts of the thyroid cartilage: 
superiorly, to a tendinous line running along the superior part of 
the pharynx. 
constrictor pharyngis posterior. — Crico-pharyngeus. 
Situation, —Postero-superior part of the pharynx. 
Attachment, —Inferiorly, its fibres are confounded with those 
of the muscular coat of the oesophagus : superiorly, to the lateral 
parts of the cricoid cartilage. 
Relations of the three Constrictors ,—Superiorly, with the 
guttural pouches; inferiorly, with the membranous parietes of the 
phaiynx, with the os hyoides, and the thyroid and cricoid carti¬ 
lages ; laterally, with the anterior portions of the parotid gland. 
Structure of them, —Fleshy. 
Action of them, —To constrict or contract the cavity of the 
pharynx in the act of deglutition. 
9.—LARYNGEAL REGION. 
Comprehending eight pairs and one single muscle. 
hyo-thyroideus. 
Situation .—Upon the side of the larynx. 
