NEURIDIN. 277 



horseflesh, beef, human muscle, five to six days ; from haddock, five 

 days in summer ; from cheese, six weeks in summer ; from gelatin, 

 ten days at 53°; from decomposing human internal organs, three to 

 eleven days ; from cultures of the Eberth bacillus, with mydin. 

 Bocklisch has obtained it from perch, six days in summer ; from 

 barbel after three days in summer. 



It has also been obtained from fresh eggs in the preparation of 

 cholin by heating with baryta ; and also from fresh brain by heal^ 

 ing with 2 per cent, hydrochloric acid (Brieger, I., 57-61). 

 Ehrenberg (1887) found it in poisonous sausage and obtained it by 

 growing a bacillus from this source on liver and meat bouillon. 



Neuridin is almost invariably accompanied by cholin, and as the 

 duration of putrefaction increases the latter gradually decreases in 

 amount and yields a corresponding increase in trimethylamin, 

 whereas the yield of neuridin increases from day to day. The 

 amount of neuridin formed depends upon the nature of the organ 

 employed in putrefaction. The greatest yield is obtained from gel- 

 atinous tissues such as intestines ; and especially from pure gelatin. 

 On the other hand such tissues as the spleen and liver yield but 

 little. 



Neuridin comes down in the mercuric chlorid precipitate (some- 

 times it occurs in the filtrate), and can then be isolated from the 

 other bases present in a number of ways. One method is given 

 under gadinin. Another convenient method of separation is to pre- 

 cipitate it from alcoholic solution by alcoholic picric acid. The 

 picrate thus obtained is, for the purpose of further purification, re- 

 crystallized from absolute alcohol, then decomposed by extracting its 

 acid solution with ether (to remove the picric acid) and evaporating 

 the aqueous solution to dryness. The residue is now extracted with 

 alcohol and the alcoholic solution precipitated by alcoholic platinum 

 chlorid. The platinochlorid can now be recrystallized from hot 

 water. 



The free base, as obtained by the treatment of the hydrochlorid 

 with moist, freshly precipitated silver oxid, possesses an extremely 

 repulsive odor, similar to that of human semen. 



On evaporation of its aqueous solution it yields a gelatinous-like 

 mass, and at the same time slowly decomposes. It does not crys- 

 tallize when evaporated in a vacuum, and decomposes even under 

 these conditions. The same disagreeable odor is obtained when the 

 hydrochlorid is warmed with potassium hydrate. Brieger (I., 24) 

 regards this decomposition product of neuridin as an oxidation 

 product of the original substance. 



The free base is very readily soluble in water, but is insoluble in 

 ether and absolute alcohol ; difficultly soluble in amyl alcohol. It 

 gives white precipitates with mercuric chlorid, neutral and basic lead 

 acetates. When distilled with fixed alkali it yields di- and tri- 



