THE CENTRAL SENSORIUM. 605 



fact that we have here a summary of all the phenomena which 

 attend loss of functional activity: that over which the poste- 

 rior pituitary body presides. 



But this experimental section of the cord was also chosen 

 as an example of the wonderful resources of Nature when 

 life's functions are to be preserved. "If we were to continue 

 our observations only for a short time, a few hours or days/ 7 

 continues the author, "we should be apt to appraise at a very 

 low value the functions of that part of the cord which still 

 remains in connection with the paralyzed extremities. But 

 these symptoms are essentially temporary. They are the re- 

 sults of shock; they are not true 'deficiency' phenomena. And 

 if we wait for a time, we shall find that this torpor of the lower 

 dorsal and lumbar cord is far from giving a true picture of 

 its normal state; that, cut off, as it is, from the influence of 

 the brain, it is still endowed with marveleus powers. If we 

 wait long enough, we shall see that, although voluntary motion 

 never returns, reflex movements of the hind-limbs, complex 

 and co-ordinated to a high degree, are readily induced. Vaso- 

 motor tone comes back. The functions of defecation and mic- 

 turition are normally performed. Erection of the penis and 

 ejaculation of the semen take place in a dog. A man with 

 complete paralysis below the loins and destitute of all sensa- 

 tion in the paralyzed region has been known to become a 

 father (Brachet). Pregnancy carried on to labor at full term 

 has been observed in a bitch whose cord was completely divided 

 above the lumbar enlargement." 



How is this to be accounted for? Simply by the fact that 

 the "sympathetic" chain of ganglia does not constitute an 

 autonomous system, but a part of the general motor system, 

 which is able to compensate, in a measure, even for spinal 

 functions. It serves as conductor for impulses, through its 

 communicating branches, and thus supplies a bridge, as it 

 were, between the two segments of the cord: i.e., between the 

 isolated lower segment and its source of impulses, the poste- 

 rior pituitary body. The same ganglia and the splanchnics also 

 using this chain as intermediary to the adrenals, the continua- 

 tion of the quasinormal functions in the mutilated animal are 

 accounted for and the unity of the whole mechanism shown. 



