434 



TEE DIGESTIVE APPARATUS IN MAMMALIA. 



they traverse the walls of the culs-de-sac and come into direct relations with the 

 gland-cells. 



The most voluminous of these glands— or those which comprise a very great 

 number of agglomerated lobules — will be first noticed. They are the piirotid, 

 maxillary, sublingual, and molar glands, which are all pairs, and are placed in 

 proximity to the mouth, when they do not lie immediately beneath the adherent 

 face of its mucous membrane. Secondly, the less important glands— those which 

 are spread in layers under that membrane, and including the labial, Ungual, and 

 staphyline glands — will be examined. 



1. Parotid Gland (Figs. 168, 8; 247, 8). 



Preparation.— T\i\s glaud, with its excretory canal, is seen after the removal of the cervico- 

 facial panniculus and parotido-auricularis muscle. By injecting Steno's duct and the facial 

 artery and vein, the relations of these three vessels will be better seen at the maxillary fissure. 



The parotid gland is situated in the space included between the posterior 

 border of the inferior maxilla and the transverse process of the atlas. It is 



Fiff. 244. 



Fi-. 245. 



CAPILLARY NETWORK AROUND THE FOLLICLES 

 OF THE PAROTID GLAND. 



LOBULE OF PAROTID GLAND, INJECTED WITH 

 MERCURY, AND MAGNIFIED 50 DIAMETERS. 



elongated from above to below, flattened on both sides, and divided into two 

 faces, two borders, and two extremities. 



The external face, nearly plane, is hollowed in its inferior part into a 

 longitudinal channel, which is sometimes transformed into a complete canal, and 

 lodges the jugular vein after it has traversed the gland from below to its 

 superficies. This external face responds to the parotido-auricularis muscle, the 

 panniculus, the atloidean loop, a cervical ramification of the facial nerve, and 

 the posterior auricular vein. The internal face is very uneven and moulded on 

 the subjacent parts. It covers the guttural pouch, the mastoid insertion of the 

 obliquus capitis superior, levator humeri, stylo-hyoideus, the tuberosity on the 

 posterior border of the os hyoideus, the digastricus, the tendon of the sterno- 

 maxillaris, and the submaxillary gland, which is separated from it by the thin 

 cellulo-aponeurotic layer uniting the latter muscle to the levator humeri ; also to 

 the external carotid artery and its two terminal branches, the posterior auricularis, 

 the muscles of the jaw, and, lastly, the facial nerve, which often passes 

 through the substance of the gland. 



The anterior border of the gland is intimately united to the posterior border 

 of the maxilla ; it is related to the temporo-maxillary articulation, the sub- 

 zygomatic vessels and nerves, and the maxillo-muscular vessels. The posterior 



