OBSERVATIONS ON STRUCTURE Of CELLS AND NUCLEI. 161 



mucous glands of the authors (single peptic glands of Ebstein) 

 in the pyloric region of dog merge into one another. 



( C. ) The glands of Brunn er. 



I fully agree with those observers who have maintained the 

 great similarity in appearance of the cells lining the glands 

 of Brunner, and those of the pyloric end of the stomach (Schwalbe/ 

 Hirt,^ Watney-^) ; and I can likewise confirm the assertion of Co- 

 belli* and Watney^ as to their anatomical continuity, or rather 

 the gradual transition of the pyloric glands into the glands of 

 Brunner in the duodenum. As regards the minute relations of 

 the cells of the latter glands, I should especially refer the 

 reader to Schwalbe's exhaustive paper. Like Hirt, I know two 

 stages of the cells lining these gland tubes (Schlemmer^) [a) one 

 in which the cells are thin, long, columnar cells, open at their 

 free end ; their substance is transparent and containing a net- 

 work of fibrils with more or less open meshes ; the nucleus is 

 cup-shaped and pressed against the membrana propria; and 

 {b) another stage, in which the cells appear shorter and thicker, 

 the network of their substance very close, so that this appears 

 very '' granular,^' the nucleus round and near but not quite 

 close to the membrana propria. In both states the cells appear 

 longitudinally striated, but especially so in the latter. In figs. 6 

 and 7 I have represented these two states, and the difference appears 

 sufficiently clear. But just as in the case of the pyloric glands, 

 so also here the state b does not correspond to the state of secretion 

 in the sense named by Ebstein for the pyloric glands, and by 

 Hirt for the Brunner's glands, but rather to a state after pro- 

 longed secretion or exhaustion, for during the first hour or two 

 after taking food and in the state of hunger the cells always pre- 

 sent the appearances described above sub a. 



In preparations prepared with spirit, provided the cells 

 present themselves in state b, i.e. with a spherical nucleus, we find 

 in many nuclei one or two large bright particles — nucleoli — in- 

 cluded in the intranuclear network. With a high power I am 

 able to trace that these large particles are not simple structures, 

 but represent a shrunken part of the network. 



6. The Liver Cells. 



As I mentioned in the first part of this paper, Kupffer^ had 



' ' Archiv f. mikr. Anatotn.,' Band, viii, p. 133. 



" In a letter by Prof. Heideuhain to the Editor of the ' Archiv f. mikr. 

 Anatom.,' Band, viii, p. 279. 



3 L. 0., p. 477. 



4 ' Sitzungsb. d. k. Akad. d. Wiss.,' Band. 1, 1867. 

 * L. c. 



« ' Sitzungsber d. k. Akad. d. Wiss./ Band. 60, i, 1869, 

 ? ' Festschrift,' an Carl Ludwig, 1875, 



