460 THE SALIVARY GLANDS, BY E. F. W. PFLUGER. 



8. THE STROMA OF THE SALIVARY GLAND. The connective 

 tissue consists partly of membranes, partly of fasciculi of fibres, 

 which form a porous network traversing the whole organ, and 

 are commingled with a larger or smaller number of elastic 

 fibres, that are often developed to a very large extent. The 

 nuclear structures are not in general readily demonstrable, but 

 when present, appear as small oval, sharply defined, highly 

 refractile corpuscles. In some places, finely granular nucleated 

 cells are found, with thick processes, which must, in all proba- 

 bility, be also regarded as amongst the cellular elements of 

 the connective tissues. As we have already mentioned, pale, 

 flattened connective tissue cells form, according to Boll and 

 Kolliker, a reticulum around the alveoli. 



In regard to the presence of the muscular fibres that Schluter 

 states he has seen in the stroma, I beg to observe that I have 

 recently directed my especial attention to the determination of 

 this point, which on physiological grounds is of great impor- 

 tance ; and that in sections of the gland which had been stained 

 with carmine, hardened in alcohol, and examined in glycerine, 

 I have been able to satisfy myself of the presence of, in 

 some instances solitary, in others of fasciculi of smooth, fusi- 

 form muscular fibre cells, with elongated rod-like nuclei, that 

 certainly could not be regarded as constituents of the vessels, 

 and must confer some, though perhaps only slight, contractility 

 on the stroma. 



The connective tissue stroma intervening between the alveoli 

 attached to a single excretory duct is exceedingly small in 

 quantity, so that the alveoli lie closely compressed and flattened 

 against one another. The several grape-like masses of glandular 

 substance belonging to different small excretory ducts are sepa- 

 rated from one another by broader bands of connective tissue, 

 in which, when the animals are fat, fat cells are seen, resulting 

 from the conversion of connective tissue cells, so that treatment 

 with perosmic acid brings into view a delicate marbling, formed 

 of black lines, in eveiy fresh section of a gland. Where the 

 secondary and tertiary groups of grape-like glands belonging 

 to a larger excretory duct are united into a compact mass, 

 numerous lobules are formed, visible with the naked eye, and 

 divided from one another by fissures. The walls of these 



