THE SYMPATHETIC SYSTEM 267 



1. A group of ganglia situated outside of the lateral 

 chain and which do not give rise to any ganglion somatic 

 fibres. These ganglia are characterized by the fact that 

 they are located outside the viscera. 



2. A group of ganglia similar to the former, but which 

 are inside the viscera. 



The first group are called splanchnic ganglia, and most of 

 these ganglia are located in the median sagital plane of the 

 body. The second group are called intra-visceral ganglia 

 or parenchymatous ganglia. 



How do the central gangliouic fibres end in these 

 ganglia? Certain centra 1-ganglionic fibres travel with 

 the ganglion splanchnic fibres, arising from the lateral 

 column or lateral vertebral ganglia and with them, reach 

 the splanchnic ganglia where they end as did the fibres of 

 the first type, by communicating, with a ganglionic cell, 

 from which arises a ganglion-splanchnic fibre. Other 

 central ganglionic fibres go further and reach the paren- 

 chymatous ganglia, where they communicate with a 

 ganglionic cell; from this cell will arise the splanchnic- 

 ganglionic neuron. Therefore should we look at the 

 central ganglionic -fibres and the ganglion-splanchnic 

 fibres we see that according to their endings in successive 

 ganglia, the fibers which reach these ganglia get longer 

 and longer and inversely the ganglion-splanchnic fibers 

 are respectively shorter and shorter. 



VARIATIONS OF ENDINGS AND COMMISSURE AL FIBRES. 



Proceeding always from the simple to the more complex, 

 I will now describe the variations of endings in the dif- 

 ferent ganglia of the various successive groups of ganglia, 

 then I will describe the commissureal fibres which unite 

 the ganglia of the lateral vertebral column to each other. 



