LIGAMENTS OF THE LAKYNX. 1067 



parts, viz., one median and two lateral, all of which are directly continuous with 

 one another, and differ only. in the nature of their upper connexions. The median 

 part (crico-thyreoid ligament) of the conus elasticus is strong, tense, and elastic. 

 It is triangular in shape, and is attached by its broad base to the -upper border 

 of the arch of the cricoid cartilage, whilst its apex is fixed to the medial part of 

 the lower border of the thyreoid cartilage (Fig. 845, p. 1063). It is pierced by 

 minute apertures, and is crossed superficially by the crico-thyreoid branch of the 

 superior thyreoid artery. The median part of the conus elasticus, therefore, closes, 

 ventrally, the interval between the cricoid and thyreoid cartilages. The lateral 

 part, on each side, presents very different connexions. It is not attached to the 

 interior border of the thyreoid cartilage, but slopes upwards and medially on the 

 inner side of the thyreoid lamina, and thus diminishes materially the transverse 

 or frontal width of the cavity of the larynx. Its attachments are very definite. 

 Inferiorly it is fixed to the superior border of the cricoid cartilage immediately 

 subjacent to the lining mucous membrane of the larynx ; above it is directly 

 continuous with the vocal ligament or 

 supporting band of the vocal fold. That g| 

 ligament, indeed, may be looked upon as | Arytamoid cartilage 



> i -i -i P / Muscular process 



constituting the superior thickened free \\ / / 



border of the lateral part of the conus O^-J. ^r^~~~^\ 



elasticus. Ventrally the lateral part of X^/ ! / \^ Vocal proce8fl 



the conus elasticus is attached to the ]!?( / / ikl 



inferior half of the medial surface of the JjjJ^v^ j J 



lamina of the thyreoid cartilage, close to ^sr^m^^^i '^f~jT Rima glottidis 



the angle, and, dor sally, to the inferior / Aa^tegjS llSr / 



f .LI. T J.-L / \ 1 y%&Sr~f- Ligament of 



border of the processus vocans of the / V JS ^jmj ^ ^ vocal fold 



arytsenoid cartilage. In contact with the Wij& ~ !?"* f c nus 



OUter Surface Of the lateral, part Of the \ /* _|^F Facet on cricoid for inferior 



conus elasticus, and separating it from ^ 



the thyreoid lamina, are the lateral crico- [^JfjjSjjjj^m ~~ Cricoid car t ila se 



arytsenoid muscles ; the inner surface is jj^ 



clothed with the lining mucous membrane \r |< ffW 



of the larynx. ll, = n ,^fjj m 



Ligamentum Vocale. The vocal liga- 

 ment (O.T. inferior thyreo -arytsenoid lig.) FIG 848. -DISSECTION TO SHOW THE CONUS 



.,, ,-, ELASTICUS. The right lamina of the thyreoid 



18 formed in Connexion With the Superior cartilage has been removed. 



border of the conus elasticus, and con- 

 stitutes the supporting ligament of the vocal fold (O.T. true vocal cord). It is 

 attached ventrally, close to its fellow of the opposite side, to the middle of the 

 angular depression between the two laminae of the thyreoid cartilage. From 

 there it stretches dor sally, and becomes incorporated with the tip and superior border 

 of the processus vocalis, which projects ventrally from the base of the arytsenoid 

 cartilage. The vocal ligament is composed of yellow elastic fibres, and embedded 

 in its ventral extremity there is, frequently, a minute nodule of elastic cartilage. 

 Its medial border is sharp and free, and is clothed with mucous membrane, which 

 I in that position is very thin and tightly bound down to the ligament. 



Ligamentum Ventricular e. The ventricular ligament supports the ventricular 

 fold (O.T. false vocal cord). It is weak and indefinite, but somewhat longer than 

 the vocal ligament. Ventrally it is attached to the angular depression between 

 the two laminae of the thyreoid cartilage, above the vocal ligament and close to 

 the attachment of the thyreo-epiglottic ligament; it extends, dor sally, to be fixed 

 to a tubercle on the ventro-lateral surface of the arytsenoid cartilage, a short dis- 

 tance above the processus vocalis. It is composed of connective tissue and elastic 

 fibres which are continuous with the fibrous tissue in the ary-epiglottic fold. 



Epiglottic Ligaments. The epiglottis is bound by ligaments to the base of 

 the tongue, to the wall of the pharynx, to the hyoid bone, and to the thyreoid 

 cartilage. The glosso-epiglottic fold is a prominent median fold of mucous 

 membrane which proceeds from the middle of the ventral free surface of the 

 epiglottis to the root of the tongue. The pharyngo-epiglottic folds are similar 



