140 DR. E. KLEIN. 



by V. Ebner, Eanvier and Ewald. Ewald^ has tried to show 

 what, however, is also hinted at by v. Ebner,^ viz. that the 

 different aspect presented by the gland cells in the quiescent 

 and exhausted state of the gland is not due to a destruction of 

 the one and a new production of the other kind of cells, but to 

 a direct change of one into the other, the " mucous cells " being 

 convertible by abstraction of mucous into the " granular 

 cells/', Lavdowsky,^ who criticises Ewald's work with what seems 

 to me unjustifiable severity, contradicts Ewald in many things 

 but on several occasions in his (Lavdowsky's) paper he 

 makes assertions which appear to me not irreconcilable with the 

 principal proposition of Ewald, and in a tolerably distinct oppo- 

 sition to Heidenhaiu's statement. Lavdowsky, on p, 338, writes 

 thus : '^ We have seen that in the transformation of the mucous- 

 cells there are two processes going on side by side, viz. the 

 diminution of mucous and the appearance of the albuminous 

 substance. Further on it becomes still more distinct that this 

 substance {i.e. albuminous substance) grows more and more (the 

 italics are Lavdowsky^s), while the mucous at the same time 



gradually dmmishes The reason for this is, according 



to Lavdowsky, '■' the increase [groiotli) of one part (albuminous or 

 protoplasmic), of ilie cell substance in order to make up for the 

 disappearance of the other part (mucous)," and on p. 329 he says 

 that as stimulation proceeds the substance of mucous cells loses 

 the character of mucous, becomes opaque, granular and smaller. 

 This seems to be clear enough; why Lavdowsky should then 

 endeavour to neutralise this again and to put such stress on the 

 destruction of mucous cells and the new formation of proto- 

 plasmic cells in the second and third of his stages of stimulation 

 I cannot well conceive. The facts such as delineated in his 

 figures 10, 11, and 13, are perfectly compatible with the first 

 view, viz. '^ gradual change of the mucous-cells into albuminous 

 cells.'* That the destruction of mucous cells mentioned by 

 Heidenhain and Lavdowky does not possess more than secon- 

 dary importance under normal conditions is a matter to which I 

 shall have to return when I give the description of my own 

 observations. 



If we examine a thin section through the submaxillary gland, 

 hardened in spirit and stained in hsematoxylin, of a dog that has 

 been killed twenty-four hours after taking food, the gland having 

 been quickly excised and plunged into the alcohol, we find that 

 it possesses a uniform structure; the gland cells resemble in 

 many respects the mucous cells that we find in ordinary mucous 



' L. c, p. 31. 



2 ' Die acuiosea Driisen der Zinige,' Graz, 1873, p. 34. 



* L. c, p. 351 and passim. 



