io LANDMARKS MEDICAL AND SURGICAL. 



run into the nose. In other instances the opening is situated 

 on the outer wall of the meatus, and is then always such a 

 narrow fissure as to be hardly discernible. The practical 

 conclusion then is, that a probe can be easily introduced 

 when the opening is in the roof of the meatus, but not without 

 difficulty and laceration of the mucous membrane when on 

 the outer wall. This difficulty indeed may be increased by the 

 narrowness of the meatus, arising from an unusual curvature 

 of the spongy bone. 



1 8. Nose and nasal cavities. The line where the carti- 

 lages of the nose are attached to the nasal and superior 

 maxillary bones can be traced with precision. The close 

 connection of the skin to the cartilages admits of no stretch- 

 ing ; hence the acute pain felt in erysipelas and boils on 

 the nose. The external aperture of the nose is always placed 

 a little lower than the floor of the nostril, so that the nose 

 must be pulled up before we can inspect its cavities. 



Looking into the nostrils, we find that the left is, in the 

 majority of cases, narrower than the right, owing to an 

 inclination of the septum towards the left. A communication 

 sometimes exists between them, through a hole in the septum, 

 as in the case of the celebrated anatomist Hildebrandt. By 

 stretching open the anterior nares we can get a view of the 

 end of the inferior spongy bone. The middle spongy bone 

 cannot be seen : its attachment to the ethmoid is high up, 

 nearly opposite the tendo oculi. The cavities are so much 

 narrowed transversely by the spongy bones, that in the 

 extraction of polypi it is better to dilate the blades of the 

 forceps perpendicularly, and near the septum. 



19. Mouth. What can be seen and felt through the 

 mouth ? The upper surface of the tongue, ' speculum pri- 

 marum viaruml is a study in itself. We notice, on its under 

 surface, a median furrow, on each side of which stands out 

 the ranine vein, lying upon the prominent fibres of the 

 lingualis. In the middle line of the floor of the mouth is 

 the ' frenum linguae,' with the orifice of the duct of the sub- 

 maxillary gland on each side of it. The gland itself can 

 be detected immediately beneath the mucous membrane 



