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VETERINARY PHYSIOLOGY 



2. Conducting Paths 



A. Ingoing. 1. The dorsal columns of the spinal cord 

 terminate in two masses of grey matter on each side, the 

 nucleus gracilis and nucleus cuneatus. From these, fibres 



nc 



Cffen ibU. 



FIG. 83. View of the Medulla Oblongata, Corpora Quadrigemina, and the Optic 

 Thalami from above, c.l.a., posterior columns of cord ; VIII., XII., X. 

 indicate the roots of these cranial nerves ; p.c.i., the restiform body ; 

 p.c.m., the middle peduncle of the cerebellum ; p.c.s., the superior 

 peduncle of the cerebellum ; t.q. , the anterior and posterior corpora 

 quadrigemina ; c.o., the optic thalamus with pulvinar (pulv.) and ex- 

 ternal and internal geniculate bodies behind it ; e.p., the pineal body. 

 The separation of the posterior columns of the cord and the opening out 

 of the floor of the fourth ventricle is shown. (VAN GEIIUCHTEX. ) 



pass forwards (i.e. towards the ventral aspect of the medulla) 

 and cross the middle line forming the deciissation of the fillet 

 (tig. 84, F.\ The crossed fibres (fig. 85, F.) then pass up in a 

 vertical series on each side of the middle line until the pons 



