2 5 8 



THE DIGESTIVE ORGANS. 



The Submaxillary Gland (Mixed Gland).- The submaxillary 

 gland of man is a gland composed of tubules similar in shape and 

 structure to those found in the parotid gland, having a serous secre- 

 tion, and of tubules with alveolar enlargements, lined with cells 



Fig. 202. Portion of a model of a salivary gland with mucous secretion : a, intralo- 

 bular duct ; b, intermediate duct ; c, tubules and alveoli lined by mucous cells ; d, demi- 

 lunes of Heidenhain (from Bohm and DavidofT, third German edition). 



which form mucus. These mucus-secreting tubules are joined to 

 intermediary ducts which are branches of intralobular ducts with 

 striated epithelium. The mucus-forming tubules show the demi- 

 lunes of Heidenhain. The submaxillary glands of man are there- 



^-*" 



Fig. 203. A number of alveoli from the submaxillary gland of dog, stained in chrome- 

 silver, showing some of the fine intercellular tubules. 



fore mixed glands, with both serous and mucous secretion, the re- 

 spective tubules or groups of tubules showing the characteristics of 

 mucous and serous glands. In Fig. 202 is shown a portion of a 

 model of a salivary gland, with mucous secretion. 



