

FACE. 261 



The lachrymal can als, superior and inferior, arc situated 

 at the inner angle of the eyelids, in their free margin. Their 

 orifices, or puncta, present slight prominences, are directed 

 inward towards the globe of the eye, and it is necessary 

 that the lid should be slightly everted to see them. The 

 canals are at first directed vertically, the superior from 

 below upward, and the inferior from above downward; they 

 then speedily bend at a right angle and continue inward to 

 the lachrymal sac, which they usually enter by separate 

 orifices. The length of the canals is three or four lines, 

 and the lower is a little shorter and larger than the upper. 

 In introducing a probe the lid should be drawn outward, 

 so as to obliterate the angle of the canal and convert it 

 more nearly into a straight tube. 



The lachrymal sac occupies a position at right angles to 

 the lachrymal canals. It is crossed at its middle by the 

 tendo oculi, and this tendon may be made apparent to the 

 touch by drawing the lids outward. A knife entering below 

 this tendon, and just within the edge of the orbit, would 

 penetrate the sac. A probe introduced at this puncture, 

 and passing downward, backward, and outward, would 

 traverse the nasal duct, and appear in the inferior meatus 

 of the nasal fossa. 



The orifice of the nasal duct is to be found in the roof of 

 the inferior meatus of the nasal fossa, beneath the inferior 

 turbinated bone, about three quarters of an inch from the 

 ala nasi, or, it is said, " at a distance equal to that between 

 the inner angles of the eyelids." This duct may be explored 

 from its nasal orifice by means of Gensoul's probe. 



The Eustachian tube may be explored by a probe with a 

 very short curve, carried along the inferior meatus of the 

 nasal fossa, until it reaches beyond the hard palate ; then 

 turning the probe outward, it will enter the orifice, by 

 which this tube opens into the pharynx behind the inferior 

 turbinated bone. The finger passed into the mouth, and 

 turned up behind the velum pendulum palati, will detect, 

 upon the outer and upper wall of the pharynx, the cartila- 

 ginous lips, covered with mucous membrane, which charac- 

 terize its opening. 



The parotid, or Steno's duct, follows a course indicated 

 by a line drawn from the tip of the lobe of the ear, for- 

 ward, and nearly horizontally. This line crosses the mas- 

 seter muscle, at the border of which the duct turns inward, 

 to open in the mouth by an orifice in the cheek, opposite 



