274 NITROGEN BASES 



CH 3 NH 2 , dimethylamine,(CH 3 ) 2 NH, trimethylamine,(CH 3 ) 3 N. 

 putrescine, NH 2 (CH 2 ) 4 NH 2 , cadaverine, NH 2 (CH 2 ) 5 NH 2 , and 

 others rather more complex, such as choline, muscarine, 

 neurine, collidine, etc., and some of unknown constitution, 

 such as mydaleine and sepsine. These substances are known 

 as ptomaines,* from the fact that they are usually associated 

 with decomposing flesh ; some of them, such as putrescine and 

 cadaverine, are practically non-poisonous, while others are 

 highly toxic, producing increased salivation, diarrhoea, vomit- 

 ing, etc. 



On the whole, however, it is at least doubtful whether the 

 manifestations of ptomaine poisoning are to be attributed 

 entirely to these substances ; it would seem more likely that 

 they were largely due to bacterial toxins, a class of substance 

 related to the albumoses, which have the power of inducing 

 the formation in the blood of antibodies, or, as they are 

 better called, anti-toxins. Similar toxins or toxalbumins also 

 occur in certain of the higher plants, as, for example, abrin, 

 obtained from Abrus precatorius, and ricin, which occurs in 

 Ricinus. 



The so-called ptomaines are all decomposition products of 

 the complex nitrogenous substrate upon which the moulds or 

 bacteria are growing, but are not actually found within the 

 organisms themselves. 



In the higher forms of plant life, on the other hand, these 

 bases are actually secreted by and stored up in the plants ; 

 the substance muscarine, for example, occurring in the fungus f 

 Amanita muscaria. 



Considerations of space will not permit more than the very 

 briefest reference to the chemistry of these substances. 



The compounds choline, muscarine, betaine, and neurine 

 are closely related, as may be seen from their formulae : 



N(CH 3 ) 3 OH N(CH 3 ) 3 OH N(CH 3 ) 3 , N(CH 3 ) 3 OH 



CH 2 CH a OH CH 2 CHO CH 2 CO / CH=CH 2 



Choline Muscarine Betaine Neurine 



* From the Greek word ITTWJLIO. meaning corpse. 



fThe same remark applies also to the Angiosperms, which contain their 

 alkaloids stored up in different parts of their structure. 





