On the Secretory Cells. 



75 



granules in these rests simply on the granular appearance of the 

 fresh teased out cells, evidence which I readily admit to be anything 

 but conclusive. 



I may now pass to consider how the statement given above of 

 the changes which take place in the cells during digestion harmonizes 

 with the description given by Heidenhain and others. 



The serous cells, the mucous cells and the chief-cells of mamma- 

 lian gastric glands, after treatment with alcohol, are described as 

 being more granular and as staining better, in the active than in the 

 resting state ; that is, during secretion there is an increase of granu- 

 lar substance staining with carmine, and a decrease of substance not 

 staining with carmine. The granular staining substance, Heidenhain 

 considers to be protoplasmic substance ; with this I agree, except that 

 I consider the apparent granules of alcohol specimens to be parts of 

 the cell network indistinctly seen, so that I take the increase of stai- 

 ning substance in the cells to be the expression of a growth and re- 

 arrangement of the cell network. 



The non- staining substance is considered by Heidenhain, to be 

 substance stored up for secretory purposes, and comparable to the 

 zymogen granules of the pancreas ; with which I agree in part only ; 

 I consider the non- staining substance to consist of hyaline and of 

 granular interfibrillar substance, the latter only corresponding to the 

 zymogen granules of the pancreas. In all these cases, as in the pan- 

 creas, the granules disappear from the outer parts of the cells during 

 secretion, but in alcohol specimens this cannot be observed. The active 

 pancreatic cells differ in appearance in stained alcohol specimens from 

 the serous and other cells mentioned above, chiefly because, in the 

 pancreatic cells, the hyaline interfibrillar substance as well as the net- 

 work takes up the colouring matter. 



Another change has been described by Grützner and by myself 2 ) 

 as occurring in various cells during secretion. The cells, after they 

 have been actively secreting, take a darker and browner tint on treat- 



*) Cf. Handbuch d. Physiol. (Hermann), Bd. V. 1880. 



2 ) Arch. f. d. ges. Physiol. XX. §399, 1879; Proc. Roy. Soc. XXIX. p. 377, 1879; 

 Journ. of Physiol. II. p. 261, 1879; Trans. Roy. Soc. Pt. III. 1881, p. 663. 



