THE ANATOMY OF THE ADULT HUMAN SALIVARY GLANDS ^ 



to unravel the constitution of a conglomerate salivary group, such as 

 is offered by the sublingual mass. The individual elements are so 

 closely interlocked, and the ducts so small and dcUcate in structure, 

 that their relation to the entire glandular body can only be demon- 

 strated by careful differential injection of the main efferent ducts. 



The facts here recorded can be grouped under three main headings: — 

 I. Parotid gland and paraparotid separate glandular elements. 

 II. Glands of the alveoKngual area, arcus palatinus, and soft palate. 



in. Separate small glands of the lingual, labial, and pharyngeal 

 regions. 



I. THE PAROTID GLAND, AND THE SMALLER SEPARATE (oRBITAl) 

 GLANDS IN THE NEIGHBORHOOD OF THE PAROTID BUCCAL ORIFICE 



The human parotid gland in the earlier fetal stages possesses 

 a very short terminal duct in the submucous and buccinator segments. 

 The transmasseteric portion of the duct is enveloped by a gradually 

 increasing periductular glandular proliferation, which is indirectly 

 continuous with the main body of the gland. The latter is chiefly 

 subauricular in position, its caudal margin in close contact with the 

 submaxillary gland. 



Figure i shows, in a lateral superficial exposure, the parotid and 

 submaxillary glands in a human fetus of approximately five months. 



Figure 2 gives the same exposure in a fetus of approximately 

 seven months. 



In the latter preparation the duct of Stenson has differentiated as 

 a clean transmasseteric canal, without lateral derivatives, while the 

 main parotid gland is retromasseteric in position and has begun to 

 elongate in the vertical diameter, producing a distinct preauricular 

 process. 



The oblique position of the caudal mandibular margin of Fig. i 

 has been exchanged for the more horizontal line of the same shown 

 in Fig. 2, indicating the attainment of a greater vertical value of the 

 ramus. 



Comparison with adult conditions suggests that the development 

 of the ectomasseteric parotid duct and the localization of the main 

 parotid gland in a retromasseteric position is, on the one hand, due 



