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INTRODUCTION TO NEUROLOGY 



in some respects from most of the classical descriptions, no two of which 

 agree among themselves. We shall limit the application of the term 

 funiculus to the three major divisions of the white matter of each half of the 

 spinal cord, viz., the dorsal funiculus bounded by the dorsal fissure and the 

 dorsal root, the lateral funiculus lying between the dorsal and ventral 

 roots, and the ventral funiculus between the ventral root and the ventral 

 fissure (Fig. 57). 



Each funiculus may be divided in a purely topographic sense into 

 fasciculi, or collections of nerve-fibers which occupy the same general region 

 in the cross-section of the cord, such as the fasciculus gracilis of Goll and the 

 fasciculus cuneatus of Burdach (which together make up the greater part 

 of the funiculus dorsalis, see Figs. 57 and 59), and the superficial ventro- 

 lateral fasciculus of Gowers (including among other tracts the spino- 

 tectal tract and the ventral spino-cerebellar tract of Fig. 59) . These fasciculi 

 are usually mixed bundles containing tracts of diverse functional types. 



Dorsal root 



Dorsal funiculus 



Dorsal column 



Lateral funiculus 



Lateral column 



Ventral column 



Ventral funiculus 



Ventral root 



Fig. 57. Diagram of a cross-section through one-half of the spinal 

 cord to illustrate the arrangement of the funiculi of white matter and the 

 columns of gray matter. 



The true physiological units of the spinal white matter are the tracts, i. e., 

 collections of nerve-fibers of similar functional type and connections. 

 These tracts by some neurologists are termed fasciculi; and, like the other 

 tracts of the central nervous system, they are, in general, named in accord- 

 ance with the terminal relations of their fibers, the name of the location of 

 their cells of origin preceding that of their place of discharge in a hyphenated 

 compound word. Thus, the tractus cortico-spinalis arises from cells of the 

 cerebral cortex (p. 140), and terminates in the spinal cord, and the tractus 

 spino-cerebellaris arises in the spinal cord and terminates in the cerebellum 

 (p. 130). But, as already stated, there is no uniformity in the nomenclature 

 of these tracts and no two authorities agree exactly in the terminology 

 adopted. Moreover, few of the tracts have clearly defined anatomical limits, 

 in most cases the fibers of different systems being more or less mingled. 



The appearance of a cross-section through the spinal cord in 

 the lower cervical (neck) region, after staining so as to reveal the 

 arrangement of both the nerve-cells and the nerve-fibers, is seen 



