THE VOICE AND SPEECH. 641 
Fia. 476, 
Fia. 477. 
. Fie. 476.—Posterior aspect of muscles of human larynx (after Sappey). 1, posterior crico- 
- arytenoid muscle ; 2, 3, 4, different fasciculi of arytenoid muscle ; 5, aryteno-epiglottidean 
muscle 
Fig. 477,—Lateral view of laryngeal muscles (after Sappey). 1, body of hyoid bone; 2, vertical 
section of thyroid cartilage ; 3, horizontal section of thyroid cartilage, turned downward 
to show deep attachment of crico-thyroid muscle ; 4, facet of the articulation of small 
cornu of thyroid cartilage with cricoid cartilage ; 5, facet on cricoid cartilage ; 6, superior 
* attachment of crico-thyroid muscle; 7, posterior crico-arytenoid muscle; 8, lateral crico- 
arytenoid muscle ; 9, thyro-arytenoid muscle ; 10, arytenoid muscle proper ; 11. aryteno- 
epiglottidean muscle ; 12, middle thyro-hyoid ligament ; 13, lateral thyro-hyoid ligament. 
the arytenoid cartilages. These are most marked around a ver- 
tical axis, giving rise to an inward 
and outward movement of rota- 
tion, but there are also movements 
of less extént in all directions. It 
isin fact through the movements 
of these cartilages to which the 
vocal bands are attached posteri- 
orly, that most of the important 
changes in the tension, approxi- 
mation, etc., of the latter are pro- 
duced. The lungs are to be regarded 
as the bellows furnishing the neces- 
sary wind-power to set the vocal 
bands vibrating, while the larynx 
has respiratory as well as vocal 
functions, as has been already 
learned. Assuming that the stu- 
dent has a good knowledge of the 
41 
An 
Fic. 478,—Larynx, viewed from above, 
on partial dissection (after Huxley). 
Th, thyroid _cartilage; Cr, cricoid 
cartilage ; V, edges of vocal liga- 
ments bounding glottis; Ary, aryte- 
noid cartilages ; Th.A, thyro-aryte- 
noid muscle; C.a.l, lateral crico- 
arytenoid. muscle ; C.a.p, posterior 
crico-arytenoid muscle; Ar.p, pos- 
terior arytenoid muscles. 
