THE SALIVARY GLANDS 



385 



(nd secondarily, through a 

 ito the secreting alveoli or 



The lumen of the ducts is of considerable ydiameter and contains 

 the reticulated or granular particles of the secr/tion. The largerjlucts 

 lie in the connective tissue septa which inveyst the lobular groups of 

 acini. Each of these groups is derived' from the ramifications of the 

 terminal branch of an interlobular duct Vhich enters the lobule to 

 divide into numerous intralobular ducts, 

 short intermediate or intercalary portion, 

 acini. The intercalary ducts are lined bj 

 low cuboidal epithelium and are the small* 

 tubules of the gland. As the duct passes 

 into ' the acinus the tubule is increased jn 

 size, and its secretory epithelium becom/es 

 taller. The tubular acinus is more or less 

 tortuous and possesses a sacculated or alv^o- 

 lar appearance. 



The epithelium differs^ accordingly as it 

 secretes a mucous or a serous ..flujol. Thus 



the acini are either mucous or serous secret- 



--- FIG. 355. INTERCALARY 

 mg. 



""""THE" SEROUS ACINI. The serous acini 

 contain pyramidal epithelial cells of sufficient" 

 height to almost completely fill the tubule; 

 hence the lumen is very narrow. The form 

 of the secreting cells is somewhat irregular ? .intercalary duct; tf; acini. 



, , ' Highly magnified (After 



a fact which apparently depends upon 'their Flint.) 



crowded condition* within the acinus. The 



nucleus is situated in the ceritrai portion or in the proximal end of 

 the cell, and is spheroidal in sfiapej The cytoplasm is finely gran- 

 ular, the granules being more promment in the distal portion of the 

 cell. 



DUCTS AND ACINI OP 



THE HUMAN SUBMAXIL- 



LARY GLAND, CORROSION 

 MODEL. 



F, small intralobular duct, 



The epithelium rests upo 

 beneath the bases of the secre 

 'basket-cells' which here and 



cells of the secretory epithelium and thus provide cup-like depressions 



which receive the bases of the 

 of these 'basket-cells' is not at 

 nized by their deeply stained 

 within the thin cytoplasmic c< 



cells, destined to replace worn-o it secretory cells. 



The appearance of the s 



i a basement membrane within which, 

 ing epithelial cells, are certain flattened 

 there send short processes between the 



secreting cells. The function and origin 



present known. They are readily recog- 

 nd flattened nuclei which are contained 

 11 body. They may be immature acinal 



creting epithelium varies with its ac- 



