440 



THE TISSUES. 



Fi g- 283 - of an inch. Their con- 



tents are finely granular 

 throughout, and frequent- 

 ly exhibit near the nu- 

 cleus an accumulation of 

 yellow or yellowish- 

 brown larger pigment- 

 granules, which increases 

 in old age. The nuclei 

 average j^^and thenu- 

 cleoli g-^Vir of an inch. 

 The cells are more abun- 

 dant on the surface of the 

 ganglion, between the pe- 

 rineurium and the origi- 

 nal sensitive fibres; but 

 they also occupy the in- 

 terstices between these 

 fibres. They are appa- 

 rently retained in their 

 place by offsets from the 

 perineurium, and which 

 form a special nucleated 

 capsule around them, 

 called their external sheath. 

 (Fig. 284.) "Fibres of 

 Kemak" are also found 

 among the elements of 

 the ganglia (p. 429). 



By far the greatest 

 number of the ganglion- 

 cells give off pale pro- 

 cesses S^VTT to soVtf of an inch in diameter. These are continued 

 into dark-bordered and double-contoured nerve-fibres (the ganglion- 

 fibres). (Fig. 285, A.) 



Possibly apolar ganglion-cells also exist, but this is not certain j 1 

 and if there be any bipolar cells, both their ganglion-fibres are be- 



1 Apolar cells are frequently met with in the ganglia aberrantia of Hyrtl ; i. e. 

 the inconstant larger or smaller collections of cells on the posterior roots of some 

 of the larger spinal nerves. 



A lumbar ganglion of a young dog, treated with soda. 

 S. Sensitive root. M. Motor root. R, a. Anterior branch 

 of the spinal nerve. R. p. Posterior branch. In both, their 

 derivation from both roots is manifest. G. Ganglion, with 

 the cells and ganglion-fibres, g, which assist in strengthening 

 the sensitive roots, traversing the ganglion. (Magnified 45 

 diameters.) 



