RELATIONSHIP OF NEURONES. 



433 



constitute the sensory neurones of the second order. Exactly how 

 their cellulifugal neuraxes end has not as yet been fully determined, 

 but it is very probable that in this case the telodendria are repre- 

 sented by the coarse end-fibers which penetrate into the brain cor- 

 tex, and here seem to come in contact with the dendrites of the pyr- 

 amidal cells. 



Fig. 348. Schematic diagram of the reflex tracts between a peripheral organ and 

 the brain cortex : H> Cerebral cortex ; mN l , motor neurone of the first, sN 2 , sensory 

 neurone of the second, degree ; C 1 , motor cell of the spinal cord ; C 2 , sensory cell of a 

 spinal ganglion; C 3 , pyramidal cell of the brain cortex (pyschic cell) ; C 4 , nerve-cell 

 of a sensory neurone of the second degree ; n, n, n, n, neuraxes ; d, d, dendrites ; c, c, c, c, 

 collaterals ; /, t, telodendria ; sN l , sensory neurone first degree ; mN 2 , motor neurone 

 second degree. 



28 



