1910.] The Chromaphil Tissues and the Adrenal Medulla. 505 



throughout, because otherwise it is ahnost impossible to recognise them in 

 sections. 



The following species have been examined : — Dog, cat, rabbit, guinea-pig, 

 white rat, mouse, monkey (raacacus), pig, gopher (Spermophilus Franklini), 

 sciurus (species not identified). 



III. The Chromaphil Cells in the Syvipathetic Ganglia. 



According to Kohn and Kose, groups of chromaphil cells are regularly 

 found in the ganglia of the sympathetic chain, and in numerous ganglia and 

 nerves of the peripheral sympathetic plexuses. 



V. Ebner,* in reference to these cells, speaks doubtfully, " nach eigenen, 

 allerdings nur fltLchtigen Beobachtungen kann ich vorlaufig an das regel- 

 massige Vorkommen von ' chromophilen ' oder ' chromaffinen ' Zellen in den 

 Ganglien des Sympathicus bei Sangern nicht glauben und halte vor allein 

 nicht fiir erwiesen, dass die in Chromsalzen sich gelb farbenden Zellen des 

 Sympathicus mit den Markzellen der Nebenniere identisch sind, da diese 

 Farbenreaktion fiir sich allein nicht beweisend ist." He points out with 

 perfect justice that in order to prove that these groups of cells are identical 

 with those of the adrenal medulla, something further than the chrome 

 reaction is necessary, and remarks that too much stress should not be laid 

 upon the common origin of the adrenal medulla and these cells from the 

 sympathetic. 



1 must confess to having felt very similar doubts at an early stage of the 

 investigation. But although these chromaphil cells in the sympathetic 

 ganglia are not, perhaps, so common as one might be led to conclude from a 

 perusal of Kohn's papers, yet if a large number of sections be cut, one can 

 scarcely fail to find them, at any rate in the larger ganglia. 



Plate 13, fig. 3, shows a section through a group of chromaphil cells in 

 the inferior cervical ganglion of a dog. The tissue was fixed in Kohn's fluid, 

 and the sections were stained with haemalum. The group of cells measures 

 0"12 mm. by 0"1 mm., and stands out prominently from the nervous tissue by 

 reason of the brown stain of the cytoplasm, and in many cases of the nucleus 

 also. 



The mass of cells is not divided up into distinct columns and smaller masses 

 as is the case with the abdominal chromaphil body {cf. fig. 4), and the adrenal 

 medulla {cf. figs. 2 and 5), but there are traces of such division indicated by 

 wavy lines which have not taken on the chrome reaction (see fig. 3). 



The cell-outlines are for the most part distinctly seen, and are indicated in 

 many cases by a light (unstained) ring, which is again surrounded by a dark, 

 * Kolliker's ' Handb. d. Gewebelehre,' 1902, 6te Aufl. 



