6M 



THE NERVOUS SYSTEM IN GENE HAL. 



and its prolongation into the encephalon, the grey substance occupies the 

 interior, while it is spread over the exterior of the encephalic lobes and 

 envelops the white substance. 



Fig. 312. 



Fig. 313. 



MICROSCOPIC GANGLION FROM HEART 

 OF FROG. 



lUl'OLAR GANGL10MC CELLS AND NKRVE- 

 FIHRES, FROM GANGLION OF FIFTH I'AIU 

 IN LAMl'KKY. 



(In some instances, as in the cells of various parts of the spinal cord, 

 the prolongations subdivide and ramify in a curious manner, and form a close 

 network that penetrates the surrounding nervous tissue. In addition to 

 these, there are other very complex nerve cells whose structure has only 



Fig. 314. 



\ 



STKLLATE NERVE-CELL, FROM THE 

 NUCLEUS CERVICIS CORNU ( POS- 

 TERIOR VESICULAR COLUMN) OF 

 A F(ETUS OF SIX MONTHS. 

 MAGNIFIED 420 DIAMETERS. 



STRUCTURE OF GANGLIONIC NERVE-CELL. 



A, According to Benle ; n, According to 

 Arnold. a, Straight fibre ; 6, Double 

 spiral fibre ; c, Capsule of connective 

 tissue. 



recently been clearly established. These have been found in the sympathetic 

 ganglia, and each is invested in a capsule of connective tissue. In shape, 

 the cell is pyriform, and it contains a nucleus ; from the narrow end spring 

 two fibres, that pass in opposite directions when they reach the nervous 



