DEVELOPMENT OF SALIVARY GLANDS IN THE DOMESTIC CAT 303 



It therefore corresponds with the late-formed circumflex furrow in the 

 human embryo, which is the site of the early lesser sublingual sprouts 

 (Rivinian elements). These glands of the cat must, therefore, be inter- 

 preted as more caudal members of the same series, the cranial portion 

 being here suppressed. The sprouts are prehngual in situation 

 (Fig. 114) and, what is of greater import, are separated by a wide 

 interval from the diffuse glands of the isthmus, with which they are 

 continuous in the adult, forming a small corpus ghindulare in the 

 anterior pillar of the fauces, which extends ventrad and craniad into 

 the alveolingual region, to a point a few millimeters in advance of the 

 lingual nerve. The condition in this embryo proves the continuity 

 to be of secondary and late acquisition, and enables us to recognize 

 the complex nature of the body. 



The isthmian and faucial glands are numerous, especially caudad 

 (Fig. 114), where they are thickly scattered over the whole lateral wall 

 from the hngual to the secondary buccal sulcus. Along the latter 

 they are most numerous. Here a ridge is formed resembhng the 

 stomal ridge, with which, however, it is not continuous. Its dorsal 

 limit is the secondary buccal sulcus, its ventral a well-defined furrow. 

 .Along both these sulci the hemispherical sprouts of the faucial glands 

 are numerous. They diminish towards the orbital angle and are not 

 continuous with either the lesser sublingual or alveobuccal series. 



The palatine glands are continuous with the faucial series at the 

 secondary buccal sulci. They are rather numerous and scattered over 

 the whole surface of the palate, but less thickly toward the median 

 line. All are alike in structure, small hemispheric projections, com- 

 posed of basal cells alone. 



The caudal members of the orbital series must be reckoned among 

 the simple diffuse glands. In the 70 millimeter embryo three are 

 present (Fig. 114, 23) as short sohd cylinders projecting from the dorsal 

 wall of the secondary buccal sulcus near its fundus. In the adult 

 the ducts of these elements run direct from their bodies to their ori- 

 fices, without turning craniad to a sagittal course in the submucosa, 

 as do those of the first three members of the series. Here, then, we 

 find a gland series transitional in character between the keeled ele- 

 ments with advancing ducts and the simple sprouts of the diffuse 

 glands. The first three in diminishing degree belong to the class of 



