362 BACTERIA. 



The poison in this case was probably an alkaloid substance 

 that was separated from decomposing mussels by Brieger, 

 who gave to it the name of mytilotoxine. Dr. Vaughan in 

 America separated from cheese that had undergone putre- 

 factive changes a substance that he called tyrotoxine, and 

 he was able to separate from some ice cream that gave rise 

 to most acute poisoning a very similar substance. 



Jacquemart, giving an account of these ptomaines, divides them into two 

 groups those that are fluid and are volatile, that have a peculiar characteristic 

 smell, and that contain no oxygen, being in the first group ; those in the 

 second are solid, non-volatile and contain oxygen. Those of the first group 

 are soluble in ether and also slightly in amyl-alcohol and chloroform. The 

 members of the second group are usually crystalline, are soluble in water, 

 but are insoluble in alcohol, benzine, and chloroform. Although they are 

 extremely unstable they unite with acids, in excess of which, however, they 

 are soluble, when we have first a red colour and then a brown deposit of 

 acicular crystals. An excess of chloride of platinum or strong light usually 

 causes their disintegration. It should be remembered that corrosive 

 sublimate does not precipitate some of these alkaloids, although there is 

 undoubtedly a salt formed which can be obtained in white crystals by 

 evaporating from watery solutions. The only substance that gives invariable 

 reactions with all these ptomaines is phosphomolybdic acid. 



The following ptomaines contain no oxygen : Parvoline, described in 

 1 88 1 by Gautier and Etard, who obtained this substance from putrefying 

 mackerel and horse-flesh ; its formula is CgH^N (also given as C 9 H I3 N). 

 It is a light yellow substance readily soluble in water, alcohol, ether, and 

 chloroform, it turns brown on contact with the air ; with chloride of platinum 

 it forms a somewhat insoluble crystalline flesh-coloured substance, which 

 rapidly becomes rose-coloured on exposure to the air. These authors also 

 described a substance Hydrocollidine (formula CsH IS N, sometimes given 

 as having two atoms less hydrogen). It is a colourless, oily fluid, becoming 

 brownish on exposure to the air ; when treated with carbonic acid gas it 

 becomes sticky. It forms a double salt with chloride of platinum, a pale 

 yellow crystalline insoluble substance, though it dissolves on heating 

 without undergoing any disintegration. Collidine, with the formula 

 CsHjjN, was first obtained from decomposing pancreas and gelatine. It is 

 a yellowish, mobile fluid with an extremely offensive odour, very soluble in 

 water, but much more soluble in methyl and ethyl alcohol and in ether. 

 Neuridine, C 5 H I4 N 2 , Cadaverine, CsHxeNs (sometimes given as isormeric 

 with neuridine). Putrescine, C 4 H I2 N 2 , Saprine, C 5 H I4 N 2 , and Mydaleine, 

 all belonging to this group, have been already mentioned. The 

 ptomaines that contain oxygen hold a kind of intermediate position 

 between the above group and the Leucomames or physiological alkaloids. 



Neurine, C 5 Hi 2 N (OH), is a strong base exceedingly soluble in water. 

 Choline, C 5 H 1S NO 2 , Muscarine, C S H I5 NO ? (or C 5 H I3 NO 2 , or Choline from 

 which H 2 has been removed by nitric acid), and two other ptomaines 

 described by Pouchet, and having the formulae C 7 H I3 N 2 O 6 and C 5 H I2 N 2 O 4 , 

 make up the solid ptomaines of the second group ; whilst Gadinine 

 C 7 H I7 NO 2 is not solid, although in other repects it resembles the members 



