DE. J. MUEIE ON THE FORM AND STEUCTURE OF TUE MANATEE. 199 



p.a, pulmonary artery ; ao, aortic arch, and ao*, abdominal aorta ; l.c, left common 



carotid artery; Is, left subclavian; i, innominata; r.c, right carotid; th, thoracic 



branch ; ic, internal carotid ; ec, external carotid ; m, internal maxillary and plexus ; 



/, facial ; rs, right subclavian ; t.ax, thyroid axis, and ax, axillary trunk splitting into 



retial divisions ; b.rete, brachial retial plexus ; im, internal mammary ; ve, portion of 



vertebral artery under the pneumogastric nerve. 

 I.J, left internal jugular, and E.J, external jugular veins ; CO, communicating branches 



of the same ; S. V, left subclavian vein, cut short ; BC, ditto brachio-cephalic ; VCD 



& VGA, vena cava ascendens and descendens, severed. 

 Nerves : — Nos. 2 to 8 numerically apply to the individual elements of the cervical and 



brachial plexus ; ^j/t, phrenic ; pu, pneumogastric ; rl, recurrent laryngeal ; si, superior 



laryngeal ; %, hypoglossal ; il, inferior laryngeal ; fn, facial nerve ; It, long thoracic ; 



mn, median nerve ; ec, external cutaneous ; un, ulnar nerve. 

 Larynx, glands, &c. : — C, cricoid, and T, thyroid cartilage ; bh, basihyal ; sJi, stylo-hyal, 



and *, its cranial cartilage ; tr, trachea ; Pgl, parotid gland ; Mgl, mammary gland ; 



r', first rib ; st, sternum reflected ; c^, the three sternal cartilages ; P, pericardium 



opened; oe, oesophagus, in part. 

 Muscles : — Ma, masseter ; Stm, sterno-mastoid ; Pc &g., panniculus &c. reflected ; Pma 



8cPmi, pectoralis major and minor; Eo, external oblique, a portion; D, diaphragm; 



Ci(A, crico-thyroid ; TA./i, thyro-hyoid ; iS'/j, stylo-hyoid ; *S/;/?, stylo-pharyngeus ; Mh, 



mylo-hyoid. 



PLATE XXV. 



Illustrations of the brain of the female, partly from rough sketches when fresh, and 

 partly from the hardened brain, aided by a cast of the cranial cavity. All about 

 natural size. 



Fig. 31. Upper surface. 

 Fig. 32. View in profile. 

 Fig. 33. The base, with origin of nerves. 



Fig. 34. Longitudinal and vertical mesial section, or inner face. 



Fig. 35. Left hemisphere, exposing lateral ventricle; the horizontal section of the 

 cerebellum is cut at a lower plane than is the cerebrum. 



The following lettering applies throughout : — 

 Nerves:— 1, 2, 3, 4, 5, 6, 7, 8, 8*, 9 ; that to the olfactory is placed on the bulb. 

 Parts of base : — pi, pineal gland ; al, corpora albicantia ; cr, crus, or peduncle ; pv, pons 



Varolii ; ap, anterior pyramid. 

 Interior horizontal and vertical sections : — ac, anterior cornu ; dc, descending cornu ; pc, 



posterior cornu; cs, corpus striatum; ts, taenia semicircularis ; th, thalamus opticus; 



hmi, hippocampus minor ; f, fornix ; cc, corpus callosum ; g, its genu, and sp, sple- 

 VOL. VIII. — PART III. September, 1872. 2 G 



