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PHYSIOLOGY OF CENTRAL NERVOUS SYSTEM. 



these long tracts are more conspicuous and form a larger percentage 

 of the total area of the cord. A physiological corollary of this 

 conclusion should be that in man the independent activity of the 

 cord is less marked than in the lower vertebrates, and this deduc- 

 tion is borne out by facts (see p. 139). 



Specific Designation of the Long Spinal Tracts. The tracts 

 that are most satisfactorily determined for the human spinal cord 

 are indicated schematically in Fig. 70. 



They are named as follows : In the posterior column, 



1. The tract or column of Goll fasciculus gracilis. 



2. The tract or column of Burdach fasciculus cuneatus. 



Pig. 70. Schema of the tracts in the spinal cord (Kolliker) : g, Tract of Goll; 6, tract 

 of Burdach; pc, crossed pyramidal tract; pd, direct pyramidal tract; /, tract of Flechsig; 

 gr, tract of Gowers. 



In the lateral column, 



1. The crossed pyramidal tract, also known as the lateral 

 pyramidal tract or the fasciculus cerebrospinalis lateralis. 



2. Flechsig's tract, known also as the direct cerebellar tract, 

 the dorsal cerebellar tract, or the fasciculus cerebellospinalis. 



3. Gowers's tract, known also as the ventral cerebellar tract 

 or the fasciculus anterolateralis superficialis. 



4. The anterolateral ground bundle, made up chiefly of short 

 association fibers. 



In the anterior columns, 



1. The direct pyramidal tract, known also as the anterior pyram- 

 idal tract or the fasciculus cerebrospinalis anterior. 



