ceo 



ANATOMY OK VERTEBRATES. 



In the green Monkey (Cercopithecus salaam), the structure of 

 the larynx accords with that in Mncacns } and Cynocephalus* In 

 fig. 473, B shows the ex])anded and excavated basihyal, /, wiih 

 the attached thyiohynls: in A, a is the epiglottis, I the basihyal, 

 c the hvoid sac, <7 the thyroid cartilage, e the trachea. 



*' tJ 



]Vo tailless Ape has the medial aperture and hyoid sac. In 



the Gibbons the larynx is relatively large, the vocal cords well 



** *i ~ 



defined, with deep intervening ventricles, from one of which is 

 continued the sac projecting into the thyro-hyoid space. If 

 Mycetes has the loudest cry, the Gibbons have the greatest range 

 of nctes ; they alone, of brute Mammals, may be said to sing. I 



473 



474 



Larynx of Cercopithecus sabsens. t'ccxx. 



Laryugeal pouch of the adult Orang-utan. 



heard, with astonishment, the Wouwcu (Hylolates agilis), captive 

 at the Zoological Gardens, emit the rising and falling scale of 

 semitones, throughout the octave, which Martin has accurately 



rendered in the musical notation o-iven in ccxx". In the Grants 



~ ~ 



the sacculi continued from the intercordal ventricles pass out be- 

 tween the thyroil and hyoid, and in the adult males extend 

 over the fore part of the neck and upper part of the chest, 

 being subdivided into several pouches, as in fig. 474, the low r est 

 of which may be crossed by the pectoralis major. In the young 

 Chimpanzee ( Troglodytes niger), the laryngeal sacculi, fig. 475, 

 a, a, produced from the ventricles extend upward and outward, 

 the left, in the specimen dissected by me, being continued for- 



1 xx. vol. ii. p. 110. tig. 1173r. 



2 xx. vol. ii. No. 1173 A. 



