Monkeys of the old continent.—Os hyoicles base excavated (fig. 895, n). Sim. Hamad ryas, larynx destitute of sac.-1-. Larynges perfo rated, sacs in the thyro-hyoid space. S. cyno cephalus, S. mona, S. cercopithecus (fig.695, A), S. Malbrouch, S. JEthiops, S. rubra, S. Ve ter $, and S. Inuus *, two sacs. Laryngeal aperture situated at the base of the epiglottis, oval or circular. Voice acute ; quality hoarse : cause, laryngeal sacs.
ridge rising from the posterior surface, the cartilage tapering towards.the anterior surface which is very narrow ; Crico-thyroid space: large ; Epiglottis : apex obtuse.
In the monkeys of America, some species have sacs appended to the larynx, the most complicated form of which is observed in Simla Seniculus, or Red Howling Monkey.— Os hyoides, base excavated ; opening quad rangular. Thyroid, volume three times that of man.* Cricoid elliptical, nearly osseous. Pomum large and excavated, into which pris sacs open ; sacs also communi cating with the larynx by a semilunar open ing at the base of the epiglottis. Arytenoids small. Cuneiform, absent ; instead of them, prominence.f Vocal ligaments : superior im bedded in tendino-cartilaginous masses t ; in ferior inserted at base of pomum. Ventricles passing on each side of epiglottis, which is connected with an infundibuliform sac, po mum, and oval pharyngo-laryngeal sacs.§ Voice intense ; howl discordant.
S. Appella and S. — Os hyoides not excavated. Thyroid, cricoid, and aryte noid, like man. Cart. Santorini large, and curved backwards. Cuneiform absent ; their
place supplied by fatty tendino-cartilaginous masses meeting each other to form a channel for the passage of air : in shape like the letter S. Voice: quality like a flute, hence called Whistling Apes ; expression, a plaintive me lody, from which they are also called Weeping Apes.
S. Rosalia. Larynx perforated at the thyro-cricoid ligament, below the thyro-aryte noid ligament ; aperture circular, sac small.
S. Coaita. Larynx like the Sapajous. Tra chea dilated behind the cricoid cartilage.
S. Aides arachnoides.—Os hyoides : base quadrangular, excavated. Larynx : cartilages of Santorini with masses substituted for cunei form cartilage. Vocal ligaments : superior give rise to the cuneiform masses ; inferior lie over the superior If at their insertion.** Epiglottis : apex notched and connected with the cuneiform fibro-cartilaginous masses. Voice acute ; quality hoarse ; melody, a plaintive cry.
Lemur. L. gracilis. — Os hyoides : base not excavated. Larynx : no sac. H. 0'33 in. Thyroid: wings united at an obtuse angle; margins, superior oblique, inferior parallel to superior. Cricoid elliptical ; margins, supe rior and inferior depressed. Crico-thyroid: chink large, rhomboidal. Epiglottis rounded ; at its base a pit. L. 0.138 in.
L. tardigradus. Cornua elongated and united with first ring of trachea.ff In Lem. Mongoz and L. Catta are processes running from the epiglottis to os hyoides. Voice in Mongoz, a peevish kind of cry when irritated.