84 THE SURGICAL ANATOMY OF THE HORSE 



placed at a short distance anteriorly to the seat, as is also the cervical 

 branch of the seventh cranial nerve, which descends obliquely down- 

 wards and backwards to the jugular furrow. The last-mentioned 

 nerve is also more deeply seated. 



The gland will be found to be very loosely applied to the atlantal 

 wing by means of a quantity of areolar tissue. This may be easily 

 broken down with the finger, and the styloid process of the occipital 

 bone will then be distinctly felt. By gently pushing the posterior edge 

 of the gland forwards, the styloid-cornu of the hyoid bone may be felt as 

 a flat plate, and running downwards and forwards to the cornu from 

 the styloid process of the occipital bone is a small flat muscle. This 

 is the occipito-styloU, which lies right over the pouch. 



Having felt these various structures, an incision should be made in 

 the occipito-styloid muscle, the incision being in the direction of the 

 length of its fibres, care being taken to avoid the posterior auricular 

 artery. 



Through this incision a curved probe with a blunt " ball" extremity 

 should be introduced, and so manipulated that the ball presses against 

 the outer part of the floor of the pouch. 



The position of the probe will then be evident on the exterior by a 

 prominence appearing near the angle of the jaw in the triangle of 

 Virborg. In this situation another incision should be carefully made, 

 after the manner described in Virborg's method, down on to the 

 probe, and through this lower opening the pouch may be emptied. 



The openings should be kept patent by a seton tape passed through 

 both, from above downwards, and the affection thereafter is treated 

 as an ordinary abscess. 



