Cha 



THE SALIVARY GLANDS. 



179 



glands, such as the parotid of man and mammals, 

 the sub-maxillary and orbital of the rabbit, the sub- 

 maxillary of the guinea-pig. They secrete true, thin, 

 watery saliva. 



(2) Mucous glands, such as the sub-maxillary and 

 orbital of the cat and dog (Fig. 107), the sub-lingual 



Fig. 107. From a Section through the Orbital (mucous) Gland 

 of Dog. Quiescent state. 



The alveoli are lined with transparent " raucous cells," and outside 

 these are the demilunes of Heidenhain. (Heidenhain.) 



of the cat, dog, rabbit, and guinea-pig. They secrete 

 thickish mucus. 



(3) Mixed salivary, or muco-salivary glands, such as 

 the sub-maxillary and sub-lingual in man and in the ape. 



In addition to the three salivary glands (parotid, 

 sub-maxillary, and sub-lingual) there are in some 

 cases, as in the rabbit and the guinea-pig, two minute 

 additional glands, one intimately annexed to the 

 parotid and the other to the sub-maxillary, and both 

 of the nature of a mucous gland. These are the 

 superior and inferior aclmaxillary glands 



