494 



From this cord, ventral and dorsal niednllated rootlets take 

 origin. 



Examining sections tlirongh tiie central end of the stalk (fig. 16), 

 the central canal widens. The lateral part of the medulla disappears 

 and oiilj a ventral rest of nervons tissue remains lined by the 



I'^ig. 1. Wall of the tumor and stalk. 



ependyma of the central canal, now irregularly shaped and wound 

 in an irregular way. The membrana vascularis ahso divides in two 

 meml>ranes, leaving a hole between them. 



Examining sections through the stalk, towards its 

 entrance in the skin ((ig. Ic), the central canal soon / ^ 

 closes dorsally. Its shape changes into another form, /y \\ 

 then it ends into many branches, one of which may be 

 followed, lying excentrically, to the end. 



At that monjent the nervous tissue is represented by a. strongly 

 niednllated fibres of the medullar columns b. medullated posterior 

 roots with well developed spinal ganglia (fig. \c). 



At the moment that the stalk reaches the skin, there is found, 

 ventrally from what seems to me to be the caudal end of (he spinal 

 cord, a lube, which soon appears to be the intestinal tube. 



Sectioning the wall of the tumour, caudally from the entrance 

 of the stalk, it appears to contain the caudal end of an imperfectly 

 developed, partly atrophied, foetus. 



I 



