HUBER. 



EXPLANATION OF PLATE IV. 

 Figs. 12-19. Sympathetic Cells of Reptilia. 



Fig. 12. Two sympathetic cells from the inferior cervical ganglion of Chrys- 

 emys picta ; methylene blue stain, a, neuraxis ; b, sheath nucleus of neuraxis ; 

 c, clear zone of protoplasm surrounding nucleus ; protoplasm shows chromophile 

 granules. 



Fig. 13. From section of dorsal ganglion of Chelydra serpentina, stained in 

 methylene blue. Simple pericellular plexuses, a, neuraxis of fiber ending in 

 pericellular plexus ; b, free endings of fibrils. 



Figs. 14-17. More complicated pericellular plexuses, with spiral fiber. All 

 sketched from sympathetic ganglia, Chelydra serpentina, stained in methylene 

 blue. 



Fig. 18. From section of sympathetic ganglion of Chelydra serpentina, stained 

 in methylene blue and alum carmine. A, neuraxis ; B, cell body ; C, nucleus ; 

 and D, nucleolus of large unipolar sympathetic neuron, a, a', a", three neuraxes 

 of meduUated nerve fibers, forming a spiral and ending in pericellular plexus; 

 c, capsule. 



Fig. 19. A portion of a section of an inferior cervical ganglion of Chelydra 

 serpentina, stained in methylene blue and alum carmine ; showing a number of 

 more complicated pericellular plexuses with spiral fibers, A, and one simpler 

 plexus without spiral fiber, B. Also the network of medullated and non-medul- 

 lated fibers between ganglion cells. 



