580 DE. J. MUEIB ON THE ANATOMY OF THE SEA-LION. 



G.h. Genio-liyoid. 



S.g. Stylo-glossus. 



s.l. Superior laryngeal nerve and artery. 



I. Lingual artery aud hypoglossal nerve. 



g. Gustatory nerve. 



M.h. Mylo-hyoid. 



O.h. Omo-hyoid. 



S.h. Sterno-hyoid. 



S.th. Sterno-thyroid. 



C.th. Crico-tbyroid. 



Th.h. Thyro-hyoid. 



T.gl, thyroid gland ; Sgl, sublingual gland and duct. 



Fig. 54. Side view, deep dissection, of the same regions as in fig. 53, but enlarged. 

 The lettering agrees, but there is in addition : — Ghg, genio-hyoglossus ; Thy, 

 thyroideus ; Ic, inferior constrictor ; Mc, middle constrictor ; Sph, stylo- 

 pharyngeus ; Hg, hyoglossus ; oe, oesophagus ; v, jugular vein ; ca, common 

 carotid artery, dividing anteriorly into internal and external carotids, with 

 subsidiary branches ; pn, pneumogastric nerve, superior laryngeal, pharyngeal, 

 and lingual derivatives springing and being distributed anteriorly. 



Fig. 55. Upper view of the pharyngeal constrictors and the adjoining parts : il, inferior 

 laryngeal nerve ; Sc, superior constrictor, in part ; Azu, azygos uvulae imco- 

 vered on one side ; Pp, palato-pharyngeus ; arrow leads into pharynx. Other 

 letters apply as in preceding (fig. 54) and succeeding (fig. 56), in which latter 

 portions of muscles have been removed. 



Fig. 56. A deeply dissected side view of the same region as in fig. 55. He, hyo-epiglottic. 



Fig. 57. Epiglottis and laryngeal fissure, with part of the pharyngeal membrane of the 

 left side, reflected outwards. Seen from above, and somewhat less than 

 natural dimensions : Ep, epiglottis ; sp, fatty prominences, or Santorinian 

 projections; ae, aryteno-epiglottic folds; p, papillae of the postfaucial floor; 

 a, arytenoid prominences ; ph, pharyngeal cavity. 



Fig. 58. Reduced diagrams illustrating the outline of the superior aperture of the 

 larynx in three different states of tension : 1, its natural condition ; 2, slightly 

 open, or during inhalation (1) ; 3, fully distended. The black ground marks 

 the longitudinal chink, the light the divaricating loops. 



Fig. 59. The interior left half of the larynx as displayed by a mesial longitudinal section 

 through the entire organ, but retaining the epiglottis intact : ep, epiglottis ; 

 s.p, fatty projections above the cartilage of Santorini; T, T*, sections of 

 the thyroid cartilage, the smaller portion being the narrow bridge anteriorly 

 connecting the thyroid alae; C, cricoid, in front and behind; tr, trachea; 

 s, orifice of laryngeal sac. 



Fig. 60. The deep lateral thyro-arytenoid muscles &c. The dotted outline signifies the 

 boundary of the right thyroid ala, which has been removed. L.c.a, lateral 

 crico-arytenoid ; P.c.a, posterior crico-arytenoid ; Ar, arytenoideus ; Th.d', 

 thyro-arytenoideus, its first or lower portion ; Th.a?, second or upper portion 

 of the thyro-arytenoideus ; s, laryngeal sac or pouch ; ep, epiglottis. 



