196 DE. J. MUEIE ON THE FORJVI AND STEUCTUEE OF THE IMANATEE. 



Fig. 10. Second layer of the muscles of the head, with portions of the panniculus cut 

 short to show their cranial insertions. 



0.0. Orbicularis oris. 



Bu. Buccinator. 

 B.a.o. Depressor anguli oris. 

 D.l.i. Depressor labii inferioris. 

 Pc\ Pc^, Pc^. Cheek and lip insertions of 

 panniculus. 



Te. Temporalis. 



DL Digastric, seen in part. 



Ma\ Ma^. Masseter, two layers. 



L.l.s.a.n. The levator labii superior 



alseque nasi cut short and reflected. 

 L.s.p. Levator labii superioris proprius. 

 C.n. Compressor nasi &c. 



Px, Vascular plexus emerging from skull behind the mandibular condyle. 



Fig. 11. Third and deepest layer of cranial muscles as viewed in profile. The same 

 lettering is used as in the preceding. Z, zygomaticus ; Md, Mandibularis 

 muscle ; Ty, tympanic bulla. 



Fig. 12. Muscles of face and muzzle seen from above. On the right side the levator 

 labii superioris alseque nasi has been entirely removed, the dotted line 

 indicating its outline. On the left side the levator labii superioris proprius 

 and maxillary portion of panniculus have been dissected, cut short, and 

 thrown forwards. Additional letters are : — Pn, Pyramidalis nasi ; and Px, 

 infraorbital plexus of nerves, &c. 



PLATE XXII. 



Fig. 13. Pectoi-al limb, inner view. The upper layer of the forearm muscles in place, 

 and insertions into scapula and humerus of some of the thoracic ones dis- 

 played. Rh, rhomboideus; S.ing, serratus magnus; T.ma&La.d, teres 

 major and latissimus dorsi; P.ma &P.mi, pectorales major and minor; 

 i.c^c&C/;, levator claviculse and cephalo-humeral ; 5'c&^^, biceps, first and 

 second heads ; T', T^, T^, triceps, three bellies ; B.a, brachialis anticus ; 

 P.r.t, pronator radii teres ; F.c.r, flexor carpi radialis ; F.c.d, beUy and 

 palmar distribution of the common flexor of the digits; F.c.v,, flexor carpi 

 ulnaris ; PI, palmaris longus ; Ab.m.d & Fb.m.d, abductor and flexor brevis 

 minimi digiti ; Pc^\ aponeurosis from panniculus. 



Fig. 14. Upper layer, short palmar muscles. Letters as in preceding. /', superficial 

 interossei ; 1 to 5, the digits. 



Fig. 15. A similar view, but with the superficial muscular expanse (/') hooked forwards, 

 exposing deep interossei : Id, deep interosseous series. 



Fig. 16. Profile foetal skull of Manatee in the Amsterdam Museum. Nat. size. Fr, 

 frontal ; 2Ix, maxillary ; Pmx, premaxillary ; Pa, parietal ; So, supraoccipital ; 

 Sq, squamosal ; Ju, jugal, and S an adjoining sesamoid bone ; T^, tympanic ; 

 Md, mandible. The dotted line indicates continuance of ascending contour, 



