38 



SURGICAL ANATOMY OF 



probably in a great measure owing to suction caused by 

 exhaustion in the nasal duct. 



FIG. 3. 



Lachrymal apparatus and nasal duct. I. Lachrymal sac. 2. Tendo-^culi. 

 3. Valvular folds in nasal duct. 4. Orifice of nasal duct. 5. Lower turbinated 

 bone. 6. Inner wall of antrum. (Bristles introduced into the punctalachrymalia.) 



The lachrymal sac is the superior dilated extremity of 

 the nasal duct, and consists of a tube of nbro-elastic tis- 

 sue, lined with epithelium, continuous through the 

 puncta with the conjunctiva, and by means of the nasal 

 duct, with the mucous membrane of the nose. It is 

 situated at the internal angle of the eye, and is lodged 

 in a hollow formed by the os unguis and the nasal pro- 

 cess of the superior maxillary. It is covered in by the 

 skin, subcutaneous cellular tissue, orbicularis muscle, by 



