No. I.] SYMPATHETIC GANGLIA OF VERTEBRATES. 35 



this work, draws attention only to the fine fibers which 

 leave the plexuses, passing through the mucosa to reach the 

 epithelium. 



The ganglia studied by me varied in size from such as were 

 just recognizable with the naked eye to others about \ mm. in 

 their longest diameter. They were most often recognized as 

 spindle-shaped swellings in the course of one of the vagus 

 branches. They were removed to a slide and stained in ^-^^0 

 methylene blue solution in normal salt ; fixed in ammonium 

 molybdate and teased or sectioned, some of the sections being 

 further stained in alum carmine. The ganglia are surrounded 

 by a fibrous capsule, which is continuous with the perineural 

 sheath of the nerves connected with the ganglion. 



In sections, sympathetic nerve cells, medullated fibers, very 

 small medullated fibers, and Remak's fibers may be seen. 



Shape and Structure of the Ganglion Cells. — The shape of 

 the nerve cells in the sympathetic ganglia of fishes varies. 

 The cell body may be more or less regularly round or oval, and 

 from it one or several processes may have their origin. The 

 cells may therefore be unipolar or multipolar. In cells not too 

 deeply stained in methylene blue the protoplasm appears gran- 

 ular, the granules staining more deeply than the remaining 

 portion of the cell. The granules are very small, and evenly 

 distributed through the protoplasm. The granules are prob- 

 ably the chromophile granules described for other nerve cells. 

 In case the cell is deeply stained, it assumes a diffuse blue 

 color, the granules showing only very indistinctly. In my prep- 

 arations the nucleus was sometimes stained more deeply, again 

 less deeply than the protoplasm, usually showing no distinct 

 structure, although in preparations double-stained with alum 

 carmine a nucleolus may now and then be made out. The cell 

 body is invested in a nucleated capsule. 



The neuraxis arises from a cone-shaped extension of the cell 

 body. (See PI. Ill, Fig. i, a-e) In sections it is sometimes 

 difficult to make out with any degree of certainty which of 

 the several processes is the neuraxis ; for instance, e, of the 

 above figure. In the neighborhood of the cell the neuraxis 

 is non-medullated ; whether at some distance from the cell it 



