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PHYSIOLOGY. 



tegmentum. Its floor is grooved by the continuation of the median 

 groove of the fourth ventricle. Its walls are composed of gray mat- 

 ter continued from the spinal cord. 



Fillets. 



The chief fillet consists of the axis-cylinders from G oil's and 

 Burdaclr's nuclei, which decussate under the floor of the fourth ven- 



urdacb 



Fig. 249. The Mesial Fillet, Ending Chiefly in the Ventral Nucleus 

 of the Optic Thalamus and then United by New Neuraxons (Upper 

 Fillet) to Parietal Cortex. 



tricle, then pass up through the tegmentum, and chiefly end in the 

 ventral nucleus of the optic thalamus. From new neuraxons it goes 

 through the posterior part of the internal capsule to the ascending 

 parietal convolutions. It is a continuation of the sensory tract. 



The lateral fillet also starts from the nuclei of Goll and Burdach 

 and is chiefly composed of axis cylinders from the end nuclei of the 

 auditory nuclei and the superior olivary body; it then passes into 





