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HAROLD KOENIG 



Fig. 3. Peripheral chromatolysis with reduction in size and basophiha of nucleoli 

 in neurons of L-7 three days after FO. Thionin, X 700. 



Fig. 4. Generalized chromatolysis of lumbar motoneuron seven days after FO. 

 Gallocyanin, X 800. 



Fig. 5. Recovering lumbar motoneuron 21 days after FO. Note hypertrophy and 

 increased basophilia of nucleolus. Gallocyanin, X 700. 



stage. The white matter lesion occurs at a time when neurons are recovering 

 and probably results from oligodendroglial disease. 



Signs of neuronal irritability are correlated with a minimal to moderate 

 depletion of Nissl substance. Loss of neuronal function is associated with 

 severe loss of Nissl substance. In most severelv affected animals, a necrosis of 



