VOICE. 



1491 



Phoca vitnlma, or Common Sea/. Larynx : MARSUHIALIA. Kangaroo. Thyroid : mar- 

 H. 1-2 in. IhM-oid : wings united by a small gins, superior a notch in front. Arvtenoids 

 cartilaginous plate j cornua parallel to axis of large. Cuneiform Cart., ventricles and su- 

 Fig. 902. perior ligament absent. Vocal cords mem- 



branous, fold upon themselves, so that they 

 cannot be stretched* by the arytenoids. 

 Voice, when in pain, moans piteously. -j- 



Phalanger^ Vocal cords: membranes sub- 

 stituted for vocal ligaments, but, as in the 

 kangaroo, do not fold on themselves. Com- 

 mon Phalanger : vocal ligaments absent. 



Didelphis Opossum. (Fi^. 903.) Larynx : H. 

 0-288 in. Superior ligament absent. Ventricles 



Fig. 903. 



Larynx, Tongue, and Trachea of the Cat. 

 tongue ; b, epiglottis ; c, superior vocal cords ; d, 

 infinferior vocal cords. 



/ocal tube. Cricoid : depth of anterior to pos- 

 terior surface as 2 to 5. Crico-thyroid chink 

 rhomboidal. Epiglottis triangular, fixed to the 

 thyroid by cartilage. L. 0'675 in. Trachea 78 

 rings.* Voice, nearly the pitch of a soprano; 

 melody, a melancholy moaning. 



* According to Wolff, the first twelve rings are 

 complete circles, the rest overlap each other. 



1. A literal view of the Larynx of Didelphis 



Opossum. 



a, thyroid cart. ; b, cricoid ; r, crico-thyroid 

 ligament ; d, trachea. 



2. A posterior view of the same. 



c, cricoid cart.; e, laryngo-tracheal ligament; d, 



trachea. 



very small. Inferior ligament: L. 0'176 in. 

 Voice consequently acute; purrs like the cat. 

 Trachea 20 rings. 



RODENT i A. Paca. Epiglottis nearly semi- 

 circular ; at its base a blind sac. Ventricles 

 not deep. Vocal cords but little salient. 



Cavia capybara. Larynx similar to that of 

 the paca. Voice grunts like a pig. 



Lepiis cuniculus. The Rabbit. (Fig. 904.) 

 Larynx: H. 0'4 in. Thyroid: wings united at 

 an obtuse angle; margins oblique and parallel. 

 Crico-thyroid chink large. Arytenoids small, 

 pyramidal. Cuneiform cart, curved. Vocal 

 cords: superior thin and delicate ; inferior pro- 

 minent. L. 0'26 in. Epiglottis a obtuse ; apex 

 slightly notched, at the base of which are 4 

 conical cartilaginous bodies or tubercles in- 

 clined towards each other : between them, 

 b b, is a triangular space ; and a vertical 

 groove passes between the insertion of the 

 vocal ligaments from b to c. On each side 

 a ligamentous filament descends, which acts 

 on the tubercles above mentioned. The infe- 

 rior tubercles give attachments to superior 

 vocal ligaments and roof of the ventricles. 

 Office of tubercles to open the ventricles, 

 stretch the superior ligaments, and give free- 



* Cuvier. 



f Bennett's Wanderings in New South Wales. 



t The Phalanger of Cook. 



Cuvier describes two small vibrating mem- 

 branes at the base of the epiglottis, which is denied 

 by Wolff. 



5 c 2 



