CoRiAT, Chemistry of the Nervous System. 157 



tion of the sciatic nerve, and in the peripheral nerves, brain and cord 

 in polyneuritis and in all these latter, the amount present was parallel 

 with the extent of the Marchi reaction. This is easily explained if 

 we remember that the Marchi reaction depends on the preciptation of 

 metallic osmium by stearic and oleic acids which are decomposition 

 products of lecithin. The action of cholin on blood pressure has been 

 carefully studied by Mott and Halliburton, while Donath has shown 

 that the injection or intracerebral application of cholin produces in an- 

 imals, strong convulsive phenomena, and he concludes from these ex- 

 periments that the seizures in general paralysis and epilepsy are due to 

 intoxication by this alkaloid. 



In closing, we should like to say a few words on Donath's latest, 

 and in many respects, his most pretentious paper, on the significance 

 of cholin in epilepsy. He examined for cholin in sixty-four cases, de- 

 tecting it by means of the platinum compound. In addition to the or- 

 ganic cases, where its presence would be expected, he finds it in those 

 which we look upon as being functional in nature (neurasthenia). In 

 addition, he finds the myelin forms of lecithin in two of his cases. 

 This seems to us extremely doubtful and altogether inexplicable. Al- 

 though using the platinum compound as a means of detecting cholin, 

 yet according to the drawings and photomicrographs appended to his 

 paper, he does not confine himself to octahedral or hexagonal crystals 

 for a positive reaction, but labels anything and everything of crystal- 

 line nature as ''cholin," while we have always hesitated, and then put 

 down as negative, what Donath in a large number of cases calls a pos- 

 itive cholin finding. 



The bibliography appended makes no claim to completeness ; it 

 merely gives those papers directly mentioned in this review, or those 

 which have been consulted for the discussion of the material. 



