370 THE DIGESTIVE AFPABATUS IN MAMMALIA. 



point where it is reflected from tte side of the cheek on to the inferior 

 maxillary bone. It is bordered, for the whole of its extent, by the buccal 

 nerve. 



Both glands pour their secretion into the mouth by numerous salient 

 orifices which can be seen arranged in line on the buccal membrane, parallel 

 to each molar arcade. 



It may be remarked that these glands establish a transition between the 

 precedinc' and those yet to be mentioned. Their lobules are far from 

 representing so compact an agglomeration as that formed by the parotid or 

 sublingual lobules ; and they tend to separate from each other to become 

 more independent. Therefore it is that many writers regard them as distinct, 

 and describe them as superior and inferior molar glands. 



5. Labial, Lingual, and Palatine Glands. 



The lobules composing these glands are spread in layers more or less 

 thick on the inner face of the mucous membrane, instead of being 

 agglomerated in masses, as in the previous glands. Sometimes they are 

 scattered, in consequence of their small number. In general, the excretory 

 duct of each glandule opens independently into the mouth, without com- 

 municating with those of the neighbouring lobules. 



Labial Glandulce,. — These are more abundant in the upper than in the 

 lower lip, and pass beyond the commissures to be spread for a short distance 

 over the inner aspect of the cheeks. It is easy, in the living Horse, after 

 turning up the lip and carefully wiping it, to see the salivary fluid secreted 

 by these small organs escape by their excretory ducts. 



Lingual Glandules. — They form a layer under the mucous membrane at 

 the base of the tongue, and adhere very closely to the fibres of the small 

 hyo-glossus muscle, and, laterally, are continuous with the layer which 

 covers the external face of the amygdaloid mucous membrane. They are 

 also found on the side of the tongue, above the superior border of the hyo- 

 glossus longus muscle ; though these are few and scattered, and look as if 

 incrusted in the substance of the hyo-glossus muscle. 



Staphyline (^or Palatine) glandulce. — The thick layer these form under the 

 anterior mucous covering of the soft palate has been described with that 

 organ. We have only to observe here, that it is continuous, laterally, with 

 the glands at the base of the tongue, through the medium of the glandules of 

 the amygdaloid cavity ; and in such a manner, that the part of the mouth 

 immediately in front of. the isthmus of the fauces, and which might be 

 justly considered as the isthmus itself, is enveloped in a complete glandular 

 zone. In the dead body, we always find in this compartment a greater or 

 less quantity of viscid fluid, which is certainly secreted by this zone. It is 

 here, then, that the alimentary bolus is enveloped in the glutinous matters 

 intended to favour its passage in the pharynx and oesophagus ; and it is 

 worthy of notice that the constricted passage where this secretion is poured 

 out in the living animal, immediately precedes the canal traversed by the 

 bolus of food in the act of deglutition. 



DIFFERENTIAL CHARAOTEHS IN THE SALIVATIY GLANDS OF OTHER THAN SOLIPED 



ANIMALS. 



The salivary system of the Herbivora is more extensive than that of the Omnivora, 

 and especially the Carnivora. 



KiJMiNANTS. — 1. Parotid gland.— The parotid glands of the Ox are distinguished by 



