MEDULLATED NERVE FIBERS 435 



functional relations within the spinal cord persist and continue 

 as ventral root fibers. 



The aberrancy or anomalous distribution of peripheral axones 

 warns us against the making of functional interpretations based 

 altogether on the location of neurones or their processes. I 

 have had occasion to report the existence of dividing sensory 

 nerve fibers in Rana pipiens, one branch of which passed to so- 

 called visceral structures and the other to so-called somatic 

 structures. Such distributions raise the question of the value 

 of connoting significance to the distribution of nerve fibers save 

 as a convenient form of generalization. Ventral root fibers are 

 not all motor. Sensory fibers are not all visceral or somatic. 



Such anatomical findings as are presented in this paper may 

 be of value in checking up unusual physiological or pathological 

 observations. Their significance is not vitiated by the paucity 

 of fibers in comparison with the great masses of fibers in the dor- 

 sal root. Complexity of distribution is a factor which must be 

 considered in the interpretation of the value of a conducting 

 pathway. 



REFERENCES 



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Cox, W. H. 1898 Der feinere Bau der Spinalganglienzellen des Kaninchens. 

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Dunn, Elizabeth Hopkins 1902 On the number and the relation between diam- 

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1909 A statistical study of the medullated nerve fibers innervating 

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KiDD, Leonard J. 1911 Afferent fibers in ventral spinal roots. British Med. 

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