DEVELOPMENT OF SALIVARY GLANDS IN THE DOMESTIC CAT 299 



due to a mesal ilisplacement of the greater sublingual, in part to a sinking 

 ventrad of the submaxillary duct, the distance between which and the 

 oral epithelium increases more rapidly than the corresponding interval 

 for the greater sublingual. Caudad of the lingual nerve, as the sprouts 

 enter the interval between Meckel's cartilage and the digastric, the 

 relation changes. The greater sublingual, continuing more hori- 

 zontally and more directly caudad in the older embryos, crosses the 

 subma.xillary duct on its dorsal aspect from its lateral to its mesal 

 side, and thence is continued along the mesal aspect of its branches 

 in the dorsal portion of the condensation, and this, as has been said, 

 to a degree far exceeding the adult overlapping of the two glands. 

 The crossing of the ducts seems to be due to the direction taken by 

 the more active submaxillary sprout, which carries it into the ventral 

 and lateral portions of the mesenchyme condensation. These portions 

 being preempted, the greater sublingual, when it begins its tardy growth, 

 hnds room for expansion only in the dorsomesal part of the area. 



At the Ungual crossing the ducts enter into intimate and complex 

 relations with processes of the submaxillary ganglion. The large body 

 of the ganglion retains its position lateral to the ducts. It surrounds the 

 submaxillary duct with a cylindrical sheath and receives the greater 

 sublingual between two processes of its mesal surface which nearly, 

 though never quite, surround it (Fig. 146). The ganglionic sheath 

 upon the subma.xillary duct follows it far beyond the mylohyoid, and 

 persisting longest on its dorsomesal aspect, intervenes for a consider- 

 able distance between it and the greater sublingual duct. 



THE DIFFUSE GLANDS OF THE MOUTH 



By diffuse glands are meant such as are developed as simple sprouts, 

 either from the general surface of the oral epithelium or in the course 

 of a sulcus. The class comprises the following groups and series : — 



1. The inferior alveobuccal glands, "molar gland." 



2. The glands of the stomal ridge. 



3. The caudal members of the orbital series. 



4. The lesser sublingual glands, glandulae sublinguales minores, 

 or Rivinian elements. 



5. The isthmian and faucial glands. 



6. The palatine glands. 



