66 ////: 90NK6 



xteinal face is divided into two portions liy a vertical en M ; the |M,rti"ii situated in front 

 of this emst forms purl of tin- lachrymal channel. Hy its internal face, tin- lachrymal 

 l-oiie limits, o ut wurdly. this bottom of the nas:il ca\iti< .-. and covers tin- anterior eel Is of the 

 ethmoid; by its i*>.,terii>r border, within tin- orbit, it articulate* \\ith the <w plaimm of 

 thr ethmoid. 



11. Xasal l*>ne. The proper bones of the nose of Man exhibit a great analogy to 

 those of the Dog. They do not possess a natal prolongation, and they articulate with 

 the lateral cartilage of the nose. 



12. Vomer. The same general form ami relations as in solip* <N. 



13. Inferior maxillary bone. This bone in Man is in shape somewhat like a horse- 

 shoe. It is nearly of the t-aine width throughout its whole extei.t. The s\inph;. 

 vertical a eharacter peculiar to Man. lielow this symnhysis is a triangular projection, 

 the mental eminence The genial surface of the Horse is replaced by four little tnb.Tcl. s 

 termed the genial processes. Tho alveoli of the molar teeth form a great projection on 

 the inner face of the bone. The mylo-hyoid ridge is very developed. The .superior 

 orifice of the dental canal is covered by a little sharp lamina. From this orifice logins the 

 mylo-hyoidean groove. The coronoid process is short ; the condyle is bent towards the 

 median line, and the sigmoid notch is wide and shallow. The superior border contains 

 fourteen or sixteen alveoli. 



ARTICLE III. THE THOKAX. 



The thorax represents a conoid cage, elongated from before to behind, 

 suspended under the vertebra) of the dorsal region, and destined to contain 

 the principal organs of respiration and circulation. It is composed of bony 

 arches named ribs, thirty-six in number eighteen on each side and a single; 

 piece, the sternum, which serves for the direct or indirect support of the 

 inferior extremities of the ribs. 



THE BONES OP THE THORAX IN PAKTICULAR. 



1. Sternum of the Horse. 



This is an osteo-cartilaginous body, elongated from before backwards, 

 flattened on each side in two-thirds of its anterior extent, and from above 

 to below in its posterior third, slightly curved on itself, and situated ben< -atli 

 the thorax in an oblique direction from above to below, and before to behind. 

 It offers for study, a superior face, two lateral faces, three borders, and tioo 

 extremities. 



Fig. 37. 



THE STERNUM. 



1, The cervical prolongation (or carinifonn cartilage) ; 2, The xiphoid appendage (or ensiform 

 cartilage; 3, 3, Cavities for the articulation of the sternal cartilages; 1, Inferior border. 



Faces. The superior face, slightly concave longitudinally, represents an 

 isoscelated, lengthened triangle, the summit of which is directed forwards ; 

 it constitutes the floor of the thoracic cavity. Each lateral face comprises 

 two parts a superior and an inferior. Tho first shows eight diarthrodial 



