MUCOUS AND SALIVARY GLANDS. 135 



branching duct, like grapes on the terminals of the successive 

 little branches growing from the central stalk to form a bunch. 



tin the glands the saccules are packed together closely around 

 the ducts, and by mutual pressure are made to assume various 

 shapes. The wall of the saccule is formed of a very delicate, 

 clear, transparent membrane, on the outside of which are numer- 

 ous flattened, branching, stellate cells, the branches of which 

 anastomose one with another, and appear also to penetrate the 

 membrane in order to reach the inside of the acini. 



FIG. 61. 



Section of the Sub-maxillary Gland of the Dog, showing the commencement of a duct 

 in the alveoli. X 425. (Schfifer.) a. One of the alveoli, several being grouped round 

 theductlet (d f ). b. Basement membrane in section, d. Larger duct with columnar epi- 

 thelium, s. Half-moon group of cells. 



The cavity of the little sacks is almost completely filled with 

 large polygonal gland cells, so that only a very narrow space exists 

 in the centre. (Fig. 61.) From this space there is free communi- 

 cation to the main duct of the gland by means of the proper ductlet 

 of each saccule. In the saccules of a few glands, viz., some of 

 the so-called mucous salivary glands, another kind of cell element 

 is seen between the gland cells just described and the wall of the 



