DR. J. MURIE ON THE FORM AND STRUCTURE OF THE MANATEE. 197 
and 1, 2, 3, separate ossific centres; fo'é fo”, the parietal and occipital fonta- 
nelles; O, orbit; Mf, mental foramen. 
Fig. 17. Base of the same, additional lettering as follows:—Bs, basisphenoid; As, ali- 
sphenoid; Os, orbito-sphenoid; Pl, palatine; Bo, basioccipital ; Ho, exoc- 
cipital ; fm, foramen magnum ; Eus, Eustachian sac; Sf, sphenoidal foramen ; 
Jof, infraorbital foramen; An, anterior palatine foramen; J, incisor-cavity ; 
Mo, molars in dental sacs. 
Fig. 18. Mouth view of the partially dissected lower jaw with tongue, larynx, hyoid, 
and muscles in situ. The dotted lines respectively show the approximate 
limits of the so-called outer lips (consult fig. 7 &c.). 
6, bristles on dl, lower lip; sp, spines on Jp, lower mandibular or symphysial pad; 
T, tongue; id, inferior dental foramen; @, cesophagus; tr, trachea; Cs, constrictor 
superior; Cm, constrictor medius; S.ph, stylo-pharyngeus; Stg-+-h, stylo-glossus and 
hyoid. 
Fig. 19. The palate and portion of the upper lip of the same female Manatee. The 
dotted lines indicate the contour of the muzzle &c. (see fig. 7). 
ul, upper lip partly in outline; wp, upper callous pad =inner upper lip; 4, bristles; 
sp, palatine spines; 0h, buccal or inner labial hairs, 
PLATE XXIII, 
Fig. 20. Reduced sketch of the viscera im situ of the young male Manatee. The lower 
left lobe of the liver is partially dragged out by a hook, the better to expose 
the natural forward tilt of the great curvature of the stomach. 
I&TIYV, first and fourth gastric cavities; and JZJ, placed on liver, points to the third semi- 
spiral appendicular cavity; g/, cardiac gland; sp, spleen; Cw, at root of bifurcate 
cecum ; 7, right, and J, left, duplex lobes of liver; Gd, gall-bladder; pe, pericardium ; 
H, four cavities of heart; pa, pulmonary artery; ao, aorta; wu, umbilicus; p, aper- 
ture for penis; a, anus, 
Fig. 21. The compound stomach, sliced open to show cavities and wall-structure. 
@, esophagus; J, first gastric cavity (* and white arrow indicate its upper sacculus) ; 
gi, cardiac gland; JJ, second cornual cavity; JV, fourth cavity; d, duodenum; 
1, esophageal opening into stomach; 2, stylet entering orifice of cardiac gland; 
3, communication between J & IV stomachs; 4 & 4, two stylets passing respectively 
into the JZ & J/J cornual gastric divisions; 6, pyloric orifice; dch and pd, ductus 
communis choledochus and pancreatic duct, to the orifices of which arrows also 
point; m, gizzard-like thickening of muscular coat. 
Fig. 22. Compound stomach, denuded of its serous coat, and exhibiting the direction of 
the external layer of muscular fibres. Lettering corresponds with fig. 21. 
