DEGENERATION AND REGENERATION OF NERVES 73 



hematoxylin and carmine preparations. In an occasional fiber 

 they were quite numerous, though uniformly absent from those 

 fibers showing the larger globules of degenerated myelin with 

 enclosed segments of the axis cylinder. Figure 12 shows the 

 most marked instance of infiltration observed in this series. Here 

 it is clearly evident that not more than one nucleus belongs to 

 the sheath of Schwann. These nuclei have not been observed 

 in fibers from fowls which developed paralysis after 51 days or 

 more on polished rice. Their presence in some fibers, however, 

 is sufficient to show that trauma is not alone responsible for their 

 presence. 



I have not been able to determine the significance of these 

 wandering cells or their fate. That their participation in the 

 removal of the degenerated myehn is improbable and at most 

 can be only extremely shght, is clearly manifested by the per- 

 sistence of degenerated myelin seen in fibers of Marchi prepa- 

 rations from fowls which had been kept a long time on a re- 

 generation diet and for several months after all symptoms of 

 paralysis had disappeared. 



In nerves from these fowls, both small droplets and large glob- 

 ules of degenerated myelin still obtained, and indeed in some 

 fibers the picture resembled very closely that of degeneration in 

 medullated nerves of fowls but recently affected by paralysis. 

 There seemed to have been some little absorption of degenerated 

 myelin in the nerves of those birds kept for 4 months in regen- 

 eration, yet globulation was just as marked and the globules 

 were equally large. The globules of degenerated myelin in the 

 fibers of fowls dead just after paralysis appeared dense, while 

 in the fibers of fowls 4 months in regeneration the globules fre- 

 quently appeared honey-combed or somewhat reticulated. The 

 droplets of degenerated myelin were uniformally smaller in the 

 latter. Fowl No. 38 (leg paralysis after 22 days on poUshed 

 rice, recovery apparently complete after 59 days on regeneration 

 diet) was killed on the 108th day of regeneration or 49 days 

 after all symptoms of neuritis had disappeared. Every fiber of 

 the sciatic nerve of this fowl contained droplets or globules of 

 myelin and many of the larger globules just described. Even 



