1352 CLINICAL AND TOPOGRAPHICAL ANATOMY 



adenoids — i. e., hypertrophied post-nasal lymphatic nodules — soft bodies of irregular shape 

 blocking up the naso-pharynx. To make out how far this is the case, it is well to take the 

 nasal septum as the starting-point. 



Pharyngeal hypophyseal remnants. — In the naso-pharyngeal mucosa, a few millimetres 

 behind the posterior border of the vomer, a group of glandular cells may be found on micro- 

 scopical examination in all cases (Haberfeld), corresponding in histological appearance with the 

 pars anterior of the hypophysis. These cells are a remnant of the primitive bud that grows 

 toward the brain in front of the bucco-pharyngeal membrane to form the pars anterior of the 

 hj'pophj'sis. In some cases of pituitary disorder they give rise to a palpable tumour in the naso- 

 pharynx. 



The palate. — Between the diverging pillars of the soft palate is the isthmus 

 faucium, bounded above by the free margin of the palate, and below by the 

 dorsum of the tongue. The space between the arches (pillars), glossopalatine and 

 pharj-ngo-palatine, wdth attachments denoted by their names, shallow above, 

 widens and deepens below. Of its lateral boundaries, the posterior pillars come 

 nearer each other than the anterior. The coverings of the hard palate are chiefly 

 mucous membrane, glands, and periosteum. These are intimately blended by 

 fibrous septa, as in the superficial laj^ers of scalp and palm of the hand. Hence 

 the readiness with which necrosis takes place here. 



Hare-lip and cleft palate. — Failure of union between the mesial nasal process 

 and the maxillary process of the embryo gives rise to the deformity known as 

 hare -lip. 



The palate is developed from three primitive processes growing down from the basis cranii, 

 viz., (1) the mesial nasal process forming the premaxilla which lies in front of the anterior pala- 

 tine foramen and bears the four incisor teeth, (2) and (3) the maxillory process of either side. 

 The slighter cases of failure to unite affect only the soft palate which is the last part to fuse. 

 Complete alveolar cleft palate, which occurs combined with hare-lip and may be unilateral or 

 bilateral, represents more serious non-union. In this condition the lateral incisor may be found 

 either on the medial or on the lateral side of the cleft, which is explained by the fact that this 

 tooth is developed in the groove between the two processes (Keith). 



In paring the edges of a cleft soft palate, the following structures would be, successively, 

 cut through: — (1) Oral mucous membrane; (2) submucous tissue, with vessels, nerves, and 

 glands; (3) glosso-palatine muscle; (4) aponeurosis of tensor palati; (5) anterior fasciculus of 

 pharyngo-palatine; (6) levator palati and uvular muscles; (7) posterior fasciculus of pharyngo- 

 palatine; (8) submucous tissue, vessels, nerves, and glands; (9) posterior mucous membrane. 

 The soft palate is thicker than it seems, the average in an adult being 6 mm. (? in.). The 

 muscles widening a cleft are the tensor and levator, while the superior constrictor closes it in 

 swallowing. Of the arteries of the palate, from the external maxillary (facial), ascending pharyn- 

 geal, and internal maxillary, the largest is the descending palatine branch of the last. This 

 emerges from the posterior palatine canal close to the inner side of the last molar tooth. 



THE NOSE 



On the face the outline of the nasal bones can be easily traced, and below them 

 the lateral nasal cartilages, flat and also somewhat triangular. Below these are 

 the greater alar cartilages, curved and so folded back that each forms a lateral 

 and a medial plate. Of these, the medial meet below the septal cartilage to form 

 the tip of the nose, while the lateral curve backward, and, together with dense 

 masses of cellular tissue and fat and accessory cartilages, form the alse. 



With the speculum, especially if the head be thrown back and the tip of the 

 nose drawn up, the lower part of the septum, floor of the nose, and greater portion 

 of the inferior concha (turbinate bone) can be seen. On throwing the head 

 further back, with a good light the lower margin of the middle concha can also 

 be made out. This is much higher up and nearly on a level with the root of the 

 nasal bone. The septum often deviates to one side. The mucous membrane 

 over it is, in health, dull red in colour; that over the inferior concha is thicker. 

 The anterior extremity of the latter bone is about 1.8 cm. (f in.) behind the nasal 

 orifice, while the opening of the naso-lacrimal duct is about 2.5 cm. (1 in.) behind 

 ancl about 1.8 cm. (4- in.) above the floor, concealed by the anterior extremity of 

 the inferior concha. T\\v opening into the maxillary sinus (antrum) is situated in 

 about the, ccnlro of thf; middle meatus and 2.5 cm. (1 in.) above the floor 



Th(! olfactory area of the mucous membrane extends over the highest concha 

 (possibly also somewhat lower) and corn^sponding portions of the septum. The 

 respiratory portion is more vascular and thicker, especially over the conchse. It 

 is firmly adherent to the periosteum and perichondrium. The veins, especially 

 over the lower concha;, form a dense plexus, closely resembling cavernous tissue. 



