660 



STRUCTURE OF THE SPINAL CORD 



[CH. XLY. 



1. Loss of motion of the parts supplied by the nerves below the 

 section on the same side of the body as the injury. 



2. Loss of sensation in the same region. The loss of sensation is 

 not a very prominent symptom, and is limited to the sense of tactile 

 discrimination and the muscular sense. The animal can still feel 



FIG. 405. The above diagrams are reproductions of photo-micrographs from the spinal cord of a monkey, 

 in which the operation of left hemisection had been performed some weeks previously (Mott). The 

 sections were stained by Weigert's method, by which the grey matter is bleached, while the healthy 

 white matter remains dark blue. The degenerated tracts are also bleached. A is a section of the 

 cord in the thoracic region below the lesion ; the crossed pyramidal tract is degenerated. B is a 

 section lower down in the lumbar enlargement ; the degenerated pyramidal tract is now smaller. 

 C is a section in the thoracic region some little distance above the lesion. The degenerated tracts 

 seen are in the outer part of Goll's column, and in the direct cerebellar tract. D is a section higher 

 up in the cervical region ; the degeneration in Goll's column now occupies a median position ; the 

 degenerations in the direct cerebellar tract, and in the tract of Gowers, are also well shown. Notice 

 that in all cases the degenerated tracts are on the same side as the injury. 



sensations of pain and of heat and cold. This is more fully explained 

 in Chapter XLIX. 



3. Degeneration, ascending and descending, largely confined to 

 the same side of the cord as the injury. The most important of 

 these are shown in the accompanying diagrams (fig. 405), the small 

 text beneath which should be carefully studied. 



