580 DR. J. MURIE ON THE ANATOMY OF THE SEA-LION. 
M.h. Mylo-hyoid. G.h. Genio-hyoid. 
O.h. Omo-hyoid. S.g. Stylo-glossus. 
S.h. Sterno-hyoid. s.l. Superior laryngeal nerve and artery. 
S.th. Sterno-thyroid. . 1. Lingual artery and hypoglossal nerve. 
Cth. Crico-thyroid. g. Gustatory nerve. 
Th.h. Thyro-hyoid. 
T.gl, thyroid gland; Sg/, 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; Jc, inferior constrictor; Jc, middle constrictor; Sph, stylo- 
pharyngeus ; Hg, hyoglossus; oe, esophagus; 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: ¢/, inferior 
laryngeal nerve; Sc, superior constrictor, in part; Azu, azygos uvule unco- 
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, papille 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 (?); 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; 7, 7*, sections of 
the thyroid cartilage, the smaller portion being the narrow bridge anteriorly 
connecting the thyroid ale; C, cricoid, in front and behind; ¢r, trachea; 
8, 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. .c.a, lateral 
crico-arytenoid; P.c.a, posterior crico-arytenoid; Ar, arytenoideus; Th.a', 
thyro-arytenoideus, its first or lower portion; Zh.a’, second or upper portion 
of the thyro-arytenoideus ; s, laryngeal sac or pouch ; ep, epiglottis. 
