950 



HUMAN ANATOMY. 



subcutaneous and praetarsal ones, and all three are united at the palpebral margins 

 in a rather finely meshed plexus. Efferents pass both toward the inner and the 

 outer angle of the orbit, and the former pass downward, obliquely across the cheek, 

 in company with the facial vein, to terminate in the submaxillary nodes, possibly 

 making connections with some of the facial nodes on their way (Fig. 798). The 

 outer ones pass partly to the anterior auricular and partly to the upper parotid nodes. 

 In the conjunctiva two net-works occur, one situated in the superficial and the 

 other in the deeper layers of the conjunctival dermis. Communicating stems pass 

 between the net-works, which are much finer in the neighborhood of the corneal 

 margin than more peripherally. They come into relation with the pericellular 

 lymph-spaces of the cornea, and their efi^erents pass toward the outer and inner 

 angles of the orbit, to accompany the palpebral efferents to the submaxillary, 

 posterior auricular, and parotid nodes. 



Of the lymphatic vessels of the lachrymal gland but little is known, but in ma- 

 lignant diseases of the gland enlargement of some of the facial and anterior auricular 

 nodes has been observed, and it is probable that vessels from the gland accompany 

 the palpebral and conjunctival eflerents. The vessels from the nasal duct probably 

 partly accompany branches of the facial vein to the facial nodes, while those from its 

 lower portion pass with the efTerents from the nasal mucous membrane to the retro- 

 pharyngeal and superior deep cervical nodes. 



The Ear. — No true lymphatics have yet been observed in the tissues of the 

 internal ear, but the space which intervenes between the osseous wall of the ear 

 cavity and the membranous ear has been regarded as a lymph-space, and on that 



account has been termed the 

 Fig. 801. pe7'ily7nphatic space. It com- 



municates with the subdural 

 space of the cranium by the 

 aqueductus cochleae and by the 

 prolongations of it which accom- 

 pany the ductus endolymphaticus 

 and the auditory ner\'e. 



In the middle ear spaces 

 have been observed in the con- 

 nective tissue lining the bony 

 walls, as well as in that of the 

 tympanic membrane. In addi- 

 tion a feebly developed net- work 

 has been described as occurring 

 beneath the epithelium lining the 

 inner (tympanic) surface of the 

 tympanic membrane, efTerents 

 from it accompanying the tym- 

 panic artery and terminating in 

 the parotid nodes. 



Much more extensively 

 developed are the lymphatic 

 vessels of the external ear. 

 Beneath the epithelium covering 

 the outer (meatal) surface of the 

 tympanic membrane there is a 

 very fine net-work, whose effer- 

 ents accompany the blood-vessels, 

 radiating toward the periphery of the membrane, and eventually open partly into the 

 posterior and partly into the anterior auricular nodes. A net-work also occurs 

 throughout the entire extent of the external auditory meatus, its efTerents having 

 the same destination as those of the pinna. 



The vessels of the last named portion of the ear form a rich net-work extending 

 throughout the whole extent of the organ, and from it stems pass in three principal 



* Anatom. Anzeiger, Bd. xv., 1899. 



Posterior 

 auricular 

 muscle 



Great 



auricular 



nerve 



Supraclavicular node 



Lymphatics of posterior surface of auricle of new-born 

 child. (Staltr.*) 



