. The comparative anatomy of the domesticated animals. Veterinary anatomy. 454 THE RESFIRATOBY APPARATUS IN MAMMALIA. Fig. 229. The crico-thyroideus shortens the larynx, in bringing together the two cartilages into which it is inserted. Posterior Crico-arytenoideus (Fig. 229, 7) —This is the most powerful muscle in this region. Its fibres are directed for- wards and outwards, and originate from the bezel of the cricoid, which they cover, and from the median crest of that part. They all converge, in becoming more or less tendinous, towards the posterior tubercle of the arytenoid cartilage, on w
. The comparative anatomy of the domesticated animals. Veterinary anatomy. 454 THE RESFIRATOBY APPARATUS IN MAMMALIA. Fig. 229. The crico-thyroideus shortens the larynx, in bringing together the two cartilages into which it is inserted. Posterior Crico-arytenoideus (Fig. 229, 7) —This is the most powerful muscle in this region. Its fibres are directed for- wards and outwards, and originate from the bezel of the cricoid, which they cover, and from the median crest of that part. They all converge, in becoming more or less tendinous, towards the posterior tubercle of the arytenoid cartilage, on which they ter- minate. Covered by the oesophagus and the crico-pharyngeal muscular band, this muscle is separated from that of the oppo- site side by the median crest of the cricoid bezel. The posterior crico-arytenoid muscles dilate the entrance to the larynx, as well as the glottis, in causing the arytenoid car- tilages to rotate or swing on the cricoid cartilage, and in separating them from one another by their anterior and inferior bor- ders. They act as a lever of the first order. Lateral Crico-arytenoideus (Fig. 229, 5). — A triangular muscle, smaller than the preceding, situated between the thyroid and arytenoid cartilages, and formed of tween the cricoid cartilage and fasciculi longer in front than behind; these first ring of trachea, 10; 11, In- originate on the side of the anterior border fh7;^'d'cl1?L;'ef""'"' "' """ ^^ *h^ ^^i^«i^ Cartilage, and are directed upwards to terminate outside the posterior crico-arytenoideus, on the tubercle of the arytenoid cartilage. It is a direct antagonist of the last muscle, and, consequently, a con- strictor of the larynx. Thyro arytenoideits (Fig. 229, 6).—Lodged at the inner face of the thyroid ala, this muscle comprises two fasciculi, separated by the ventricle of the glottis. The anterior fasciculus is a long and pale band, originating on the internal surface of the ala of the thyroid c
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Keywords: ., bo, bookcentury1800, bookdecade1870, booksubjectveterinaryanatomy
