4 THE SURGICAL ANATOMY OF THE HORSE 



it, is placed the superior border of the infra-orbital foramen, which 

 gives passage to the infra-orbital branch of the superior maxillary 

 division of the fifth cranial nerve. The foramen, however, can only 

 with difficulty be felt since it is covered by the levator labii superioris 

 proprius muscle. 



By taking the alar cartilage of the nostril between the thumb 

 and index finger of one hand, and the outer lip of the nostril in 

 the other, the interior of the nostril may be exposed. The line of 

 demarcation between the skin and mucous membrane is distinctly 

 seen if the termination of the skin be indicated by the line where 

 the hairs cease to exist. On the floor of the chamber, and placed 

 in the skin a little anteriorly to where the mucous membrane begins, 

 is the inferior opening of the lachrymal duct. It is a small circular 

 opening, and appears as though a small portion of skin had been 

 excised. The false nostril should now be explored by passing the 

 index and medius fingers along the antero-superior aspect of the 

 nasal chamber. 



If the tongue be now taken in the left hand and withdrawn from the 

 right side of the cavity of the mouth, and while so held it is gently 

 twisted, the animal will be compelled to keep its mouth open. This 

 will be facilitated by insinuating two or three fingers of the right hand 

 into the left interdental space. A good view of the interior of the 

 mouth is thus obtained. 



In the median line the fraenum linguae is visible, and on either side 

 of it are placed the small elevations termed the barbs. It should be 

 noticed that on the summit of each barb is a small circular aperture. 

 This is the orifice of Wharton's Duct, the excretory duct of the 

 submaxillary salivary gland. The right hand may safely be passed 

 into the buccal cavity, and by such exploration the condition of 

 the molar teeth ascertained. 



The above method of dealing with the tongue should be adopted 

 in the administration of a ball, which should be carried with the right 



