362 ANATOMY OF THE CBNTHAL NEEVOUS SYSTEM. 



long-continuing lesion of x a, there ensues gradual participation of the part 

 c. But this occurs seldom. Interruption of the path a leads to descending 

 degeneration from the point of lesion to the level of the respective ventral 

 horn. 



As an example of paralysis and muscular atrophy, occurring with 

 disease of the ventral horns, may be mentioned "infantile spinal paralysis." 

 In this affection complete paralysis of single muscle-groups occurs suddenly, 

 and there follows very quickly wasting of the muscular tissue. Examina- 

 tion of the spinal cord reveals then disease-foci in the gray matter of the 

 ventral horns. The nerves also, as well as the anterior nerve-roots, atrophy 

 gradually. 



We do not yet possess sufl&ciently exact evidence to be able to say what 

 symptoms arise from disease of the gray matter of the dorsal horns. But 

 from the analysis of cases of tabes dorsalis, in which they were spared, and 

 of those in which they were affected, we may conclude that lesions involving 

 them lead probably to disturbances of cutaneous sensibility, and particularly 

 to trophic changes in the skin. In syringomyelia and with tumors located 

 within the gray matter among other disturbances appear those of tempera- 

 ture and pain-sense. 



